HomeMy WebLinkAboutLily Pond WTP 20-Yr CIP Report final 2021
Town of Cohasset
Lily Pond Water Treatment Plant
20-Year Capital Improvement Plan
PRESENTED TO PREPARED BY
Cohasset Water Department
339 King Street
Cohasset, MA 02025
P +1-781-383-0057
Tetra Tech
10 Post Office Square
Suite 1100
Boston, MA 02109
P +1-617-443-7500
www.tetratech.com
Tt # 200-121837-20003
August 11, 2021
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
ii 200-121837-20003
TABLE OF CONTENTS
1.0 INTRODUCTION ..................................................................................................................................................1
1.1 Background ....................................................................................................................................................1
1.2 Purpose ..........................................................................................................................................................1
1.3 Scope .............................................................................................................................................................2
2.0 WATER QUALITY AND ENVIRONMENTAL REGULATORY COMPLIANCE REVIEW ...................................3
2.1 Raw and Finished Water Quality Review .......................................................................................................3
2.2 Distribution System Disinfection byproducts Review .....................................................................................7
2.3 Environmental Regulatory Compliance Review .......................................................................................... 14
2.3.1 United States Environmental Protection Agency .............................................................................. 14
2.3.2 Massachusetts Department of Environmental Protection ................................................................. 20
2.4 Future Regulatory Considerations .............................................................................................................. 26
2.4.1 Contaminant Candidate List .............................................................................................................. 26
2.4.2 Six-Year Review ................................................................................................................................ 26
2.4.3 Revised Aluminum Criteria in NPDES Permits ................................................................................. 27
2.5 Current and Future Compliance Review ..................................................................................................... 29
2.5.1 Current Water Quality and Compliance ............................................................................................. 29
2.5.2 Future Water Quality Considerations ................................................................................................ 32
CAPACITY ANALYSIS ..................................................................................................................................... 34
3.1 Overview ..................................................................................................................................................... 34
3.2 Existing Conditions ...................................................................................................................................... 34
3.3 Historical Water Demands .......................................................................................................................... 45
3.4 Future Water Projections ............................................................................................................................ 46
3.5 Capacity and process review ...................................................................................................................... 48
PROJECT PRIORITIZATION METHODOLOGY .............................................................................................. 61
4.1 Overview ..................................................................................................................................................... 61
4.2 Condition Scale and Factors ....................................................................................................................... 62
4.3 Criticality Scale and Factors ....................................................................................................................... 64
CONDITION ASSESSMENTS .......................................................................................................................... 66
5.1 Assets.......................................................................................................................................................... 66
5.2 Process Mechanical .................................................................................................................................... 66
5.2.1 Intake Structure ................................................................................................................................. 67
5.2.2 Raw Water Pumps ............................................................................................................................. 68
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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5.2.3 Rapid Mixers ...................................................................................................................................... 68
5.2.4 Flocculators ....................................................................................................................................... 69
5.2.5 Sedimentation Basin Equipment ....................................................................................................... 70
5.2.6 Filters ................................................................................................................................................. 71
5.2.7 Wastewater Pumps ........................................................................................................................... 72
5.2.8 Finished Water Pumps ...................................................................................................................... 72
5.2.9 Sludge Lagoon .................................................................................................................................. 73
5.2.10 Plant Piping ..................................................................................................................................... 74
5.2.11 Chemical Feed Systems .................................................................................................................. 74
5.2.12 Prioritization and Service Life .......................................................................................................... 76
5.3 Electrical ...................................................................................................................................................... 77
5.3.1 Main Switchgear and Motor Control Center ...................................................................................... 77
5.3.2 Distribution Panels ............................................................................................................................. 78
5.3.3 Electrical and Instrumentation Cable Routing, Raceways ................................................................ 78
5.3.4 Transformers ..................................................................................................................................... 78
5.3.5 Grounding, Receptacles at Code Required Locations ...................................................................... 78
5.3.6 Lighting, Emergency Lighting ............................................................................................................ 78
5.3.7 Pump Motors, Variable Frequency Drives, Starters, Disconnects .................................................... 79
5.3.8 Pump Run Relays, Solenoid Valve Relays ....................................................................................... 79
5.3.9 Unit Heaters, HVAC Fan Motors, Aerator Fan .................................................................................. 79
5.3.10 Generator, Automatic Transfer Switch for Generator ...................................................................... 79
5.3.11 Overhead Motorized Door Operators at Storage Areas in Outbuilding ........................................... 79
5.3.12 Fire Alarm, CCTV, Security System ................................................................................................ 80
5.4 SCADA/Instrumentation .............................................................................................................................. 80
5.4.1 Factors Affecting Automation ............................................................................................................ 80
5.4.2 SCADA Network Devices .................................................................................................................. 80
5.4.3 Instrumentation .................................................................................................................................. 81
5.5 Structural ..................................................................................................................................................... 81
5.5.1 Water Treatment Plant Building Interior ............................................................................................ 81
5.5.2 Water Treatment Plant Building Exterior ........................................................................................... 82
5.5.3 Water-tight Retaining Wall ................................................................................................................. 83
5.5.4 Intake Structure ................................................................................................................................. 83
5.5.5 Raw Water Well ................................................................................................................................. 84
5.5.6 Rapid Mix Basins ............................................................................................................................... 84
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5.5.7 Flocculation Tanks ............................................................................................................................. 85
5.5.8 Sedimentation Basins ........................................................................................................................ 86
5.5.9 Filters ................................................................................................................................................. 87
5.5.10 Clearwell .......................................................................................................................................... 87
5.5.11 Wastewater Sump ........................................................................................................................... 88
5.5.12 Vehicle Storage and Generator Building Interior ............................................................................. 88
5.5.13 Vehicle Storage and Generator Building Exterior ........................................................................... 89
5.5.14 Lagoon Structures ........................................................................................................................... 90
5.6 Architectural/Workplace Safety ................................................................................................................... 91
5.6.1 WTP Building Exterior ....................................................................................................................... 91
5.6.2 Life Safety .......................................................................................................................................... 92
5.6.3 Vehicle Storage and Generator Room .............................................................................................. 93
5.6.4 Raw Water Intake Building ................................................................................................................ 93
5.7 HVAC .......................................................................................................................................................... 94
5.7.1 WTP Building ..................................................................................................................................... 94
5.7.2 Plumbing ............................................................................................................................................ 94
5.7.3 Intake Structure ................................................................................................................................. 95
5.7.4 Vehicle Storage and Generator Room .............................................................................................. 95
5.8 Site Civil/Security ........................................................................................................................................ 96
5.8.1 Site Paving......................................................................................................................................... 96
5.8.2 Site Security....................................................................................................................................... 96
5.8.3 Site Grading ....................................................................................................................................... 97
CAPITAL IMPROVEMENTS PLAN .................................................................................................................. 98
6.1 Description of Projects and Costs ............................................................................................................... 98
6.2 Additional Projects .................................................................................................................................... 106
6.3 Capital Improvement Plan ......................................................................................................................... 107
CONCLUSIONS AND RECOMMENDATIONS .............................................................................................. 108
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LIST OF TABLES
Table 2-1. Lily Pond WTP Raw and Finished Water Quality .....................................................................................4
Table 2-2. Surface Water Treatment Rules ............................................................................................................ 18
Table 2-3. America’s Water Infrastructure Act (AWIA) of 2018 Compliance Summary .......................................... 20
Table 2-4. PFAS6 Sampling Requirements Summary ............................................................................................ 23
Table 2-5. Monitoring Requirements ....................................................................................................................... 25
Table 2-6. USGS-MassDEP Aluminum Study (2018-2019) Preliminary Results ................................................... 28
Table 2-7. Cohasset Lily Pond WTP Historical Aluminum Data (January 2016 – January 2021) .......................... 28
Table 2-8. 2019 Microbial Compliance Sampling Results ...................................................................................... 29
Table 2-9. 2019 Inorganic Compliance Sampling Results ...................................................................................... 30
Table 2-10. 2019 Disinfectant/Disinfectant Byproducts Compliance Sampling Results ......................................... 30
Table 2-11. 2019 Radioactive Contaminants Compliance Sampling Results ........................................................ 30
Table 2-12. 2019 Lead and Copper Compliance Sampling Results ....................................................................... 31
Table 2-13. 2019 Filter Performance Compliance Sampling Results ..................................................................... 31
Table 2-14. 2019 Secondary and ORSG Contaminant Sampling Results ............................................................. 31
Table 2-15. PFAS6 Results ..................................................................................................................................... 33
Table 3-1. Permitted Maximum Authorized Daily Withdrawal Rates ...................................................................... 35
Table 3-2. Permitted Existing Authorized Rate ....................................................................................................... 35
Table 3-3. Current Demands and Installed Facility Capacities ............................................................................... 36
Table 3-4. Surface Water Supply ............................................................................................................................ 36
Table 3-5. Treatment Facilities ................................................................................................................................ 37
Table 3-6. Additional Chemical Feed Systems ....................................................................................................... 41
Table 3-7. Cohasset Water System Historical Demand Summary ......................................................................... 45
Table 3-8. Assumed Peaking Factors for Water System Planning ......................................................................... 46
Table 3-9. DCR Water Needs Forecast for Cohasset ............................................................................................. 47
Table 3-10. Capacity and Process Evaluation Results – Supply, Treatment & Sludge Management ................... 52
Table 3-11. Capacity and Process Evaluation Results – Chemical Feed Systems ................................................ 54
Table 4-1. Condition Scale ...................................................................................................................................... 62
Table 4-2. Average Service Life of Assets .............................................................................................................. 63
Table 4-3. Criticality Scale ...................................................................................................................................... 64
Table 4-4. BRE Prioritization Criteria ...................................................................................................................... 65
Table 5-1. Intake Structure Assets .......................................................................................................................... 67
Table 5-2. Raw Water Pumps ................................................................................................................................. 68
Table 5-3. Rapid Mixers .......................................................................................................................................... 68
Table 5-4. Flocculators ............................................................................................................................................ 69
Table 5-5. Sedimentation Basin Equipment ............................................................................................................ 70
Table 5-6. Filters ..................................................................................................................................................... 71
Table 5-7. Wastewater Pumps ................................................................................................................................ 72
Table 5-8. Finished Water Pumps ........................................................................................................................... 72
Table 5-9. Sludge Lagoon ....................................................................................................................................... 73
Table 5-10. Plant Piping .......................................................................................................................................... 74
Table 5-11. Finished Water Pumps ......................................................................................................................... 75
Table 5-12. Assets with Highest Ranking BRE Scores ........................................................................................... 77
Table 6-1. Process Mechanical Recommended Improvements, Timelines, and EOPC ........................................ 99
Table 6-2. Recommended Electrical and SCADA/Instrumentation Improvements, Timelines, and EOPC .......... 101
Table 6-3. Recommended Structural Improvements,Timelines, and EOPC ........................................................ 102
Table 6-4. Recommended Architectural/Workplace Safety Improvements, Timelines, and EOPC ..................... 104
Table 6-5. Recommended HVAC Improvements, Timelines, and EOPC ............................................................. 105
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 6-6. Recommended Site Civil/Security Improvements, Timelines, and EOPC ........................................... 106
Table 6-7. Summary of CIP Projects ..................................................................................................................... 107
Table 7-1. Summary of CIP Projects ..................................................................................................................... 108
LIST OF FIGURES
Figure 2-1. Lily Pond WTP Raw and Finished Water TOC .......................................................................................5
Figure 2-2. Lily Pond WTP Raw and Finished Water Turbidity .................................................................................6
Figure 2-3. Lily Pond WTP Raw and Finished Water Manganese ............................................................................6
Figure 2-4. Lily Pond WTP Raw and Finished Water Iron .........................................................................................7
Figure 2-5. Cohasset Water Distribution System TTHMs ..........................................................................................9
Figure 2-6. Cohasset Water Distribution System HAA5 ............................................................................................9
Figure 2-7. Deer High School Location TTHMs ...................................................................................................... 10
Figure 2-8. Deer High School Location HAA5s ....................................................................................................... 10
Figure 2-9. Police Station Location TTHMs ............................................................................................................ 11
Figure 2-10. Police Station Location HAA5s ........................................................................................................... 11
Figure 2-11. 2 Whitehead Location TTHMs ............................................................................................................ 12
Figure 2-12. 2 Whitehead Location HAA5s ............................................................................................................. 12
Figure 2-13. 4 Beechwood Location TTHMs .......................................................................................................... 13
Figure 2-14. 4 Beechwood Location HAA5s ........................................................................................................... 13
Figure 3-15. EPA Aluminum Criteria Calculator Schematic ................................................................................... 27
Figure 3-1. Cohasset Water System Historical Flows ............................................................................................ 46
Figure 3-2. Historical and Forecasted Water Needs .............................................................................................. 48
Figure 3-3. Lily Pond WTP Raw Water Supply Pumping Capacity vs Demand ..................................................... 57
Figure 3-4. Manganese Pretreatment Contact Capacity vs Demand ..................................................................... 57
Figure 3-5. Flocculation Capacity vs Demand ........................................................................................................ 58
Figure 3-6. Sedimentation Capacity vs Demand .................................................................................................... 58
Figure 3-7. Filtration Capacity vs Demand ............................................................................................................. 59
Figure 3-8. Disinfection Clearwell Capacity vs Demand ......................................................................................... 59
Figure 3-9. Finished Water/High Service Pumping Capacity vs Demand .............................................................. 60
Figure 4-1. Business Risk Evaluation .................................................................................................................... 61
APPENDICES
APPENDIX A – MASSDEP DRINKING WATER STANDARDS AND GUIDELINES
APPENDIX B – PRIORITIZATION WORKSHOP
APPENDIX C – CONDITION ASSESSMENT FORMS
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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ACRONYMS/ABBREVIATIONS
Acronyms/Abbreviations Definition
ADA Americans with Disabilities Act
ADD Average Daily Demand
ALs Action Levels
ATS Automatic Transfer Switch
AWIA America’s Water Infrastructure Act of 2018
BRE Business Risk Evaluation
CCT Corrosion Control Treatment
CCTV Closed Circuit Television
CMU Control Monitoring Unit
DOC Dissolved Organic Carbon
DBP Disinfection Byproducts
EBCTs Empty Bed Contact Times
EPA Environmental Protection Agency
ERP Emergency Response Plan
GAC Granular Activated Carbon
HAAs Haloacetic Acids
HVAC Heating, Ventilation, and Air Conditioning
LCR Lead and Copper Rule
LRAA Locational Running Annual Average
MassDEP Massachusetts Department of Environmental Protection
MCC Motor Control Center
MCLG Maximum Contaminant Level Goals
MDD Maximum Day Demand
MMD Minimum Month Demand
NPDWRs National Primary Drinking Water Regulations
OSHA Occupational Safety and Health Administration
PFAS Per- and Polyfluoroalkyl Substances
PLC Programmable Logic Controller
PWS Public Water System
RAA Running Annual Average
RSSCT Rapid Small Scale Column Test
SCADA Supervisory Control and Data Acquisition
SDWA Safe Drinking Water Act
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Acronyms/Abbreviations Definition
TCE Trichloroethylene
TDS Total Dissolved Solids
TOC Total Organic Carbon
TTHMs Total Trihalomethanes
UAW Unaccounted-for-water
USGS United States Geological Survey
WTP Water Treatment Plant
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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1.0 INTRODUCTION
1.1 BACKGROUND
The Town of Cohasset Water System (PWS ID#: 4065000) is a community system that serves a population of
approximately 7,200 people through 2,637 service connections throughout their water distribution system. The
Town’s distribution system is served by two water treatment facilities—the Lily Pond WTP and the Ellms Meadow
Pump Station. Surface water from the Lily Pond and Aaron River Reservoir supplies raw water to the Lily Pond
WTP.
The Lily Pond WTP, which was placed into operation in 1978, has a peak permitted capacity of 3.0 MGD and an
average daily capacity of 1.2 MGD. and operates on average eight to twelve hours per day, seven days per week.
The facility employs a conventional surface water treatment scheme, consisting of coagulation, flocculation,
sedimentation, filtration, disinfection, and stabilization. Raw surface water is withdrawn from Lily Pond and pre-
filtered through course and fine screens at the raw water intake building. An option for dosing gaseous chlorine for
pre-oxidation is also available. Following pre-screening, the raw water is conveyed by gravity to the raw water
wetwell where sodium hydroxide, and sodium permanganate are added. As the raw water is pumped to the rapid
mix tank ferric chlorideis added and mixed with the raw water. Polyaluminum chloride si added as the water neters
the rapid mix tank. Ferric chloride and polyaluminum chloride are coagulant agents that serve to destabilize the fine
particulate, colloidal, and dissolved inorganic and organic matter naturally present in the Lily Pond supply and form
small solid particles. The sodium hydroxide addition helps to maintain the pH and alkalinity at optimum levels during
the coagulation process as the addition of ferric chloride tends to depress the pH and alkalinity of the water. Sodium
permanganate is added in the process for iron and manganese removal.
The rapid mixing process is followed by gentle mixing, along with the addition of a slight dosage of polyacrylamide
polymer to promote the aggregation of the destabilized particles into larger particles or “flocs” and make these flocs
heavy enough to settle from the water in the sedimentation process. After settling, the coagulated-flocculated-settled
water is filtered through layers of fine coal and silicate sand to filter any fine flocs or particles and reduce turbidity.
Following filtration, sodium hydroxide, is added for pH control. Blended ortho/poly phosphate and chlorine is added
as the water enters the clearwell that provides contact time for disninfection . Sodium fluoride is added to promote
dental health. The finished water is stored in an 0.13 MG underground concrete clear well. The finished water is
pumped into the distribution system by the high service pump station, which consists of two pumps with a firm,
maximum capacity of 2,100 gpm.
1.2 PURPOSE
The purpose of this project is to conduct a condition assessment and develop a twenty-year capital improvement
plan (CIP) for the Lily Pond Water Treatment Plant as requested by the Cohasset Water Department (CWD). A
capital improvement plan is a management tool that includes a description of proposed capital improvement projects
ranked by priority and is used to coordinate the timing and financing of capital improvements over a multi-year
period. A comprehensive evaluation of existing assets and their current conditions is also included in this project to
help develop the CIP.
Work under the capital plan includes establishing a framework for prioritization of improvements recommendations
covering a comprehensive list of criteria including: general condition assessment, water quality and environmental
regulatory compliance, key equipment assets, water treatment effectiveness, residuals management, water
treatment process condition, building condition, and workplace safety. The prioritization plan includes aspects of
Town of Cohasset’s existing capital prioritization category weighting and rating factors, which include risk, funding
cash payback, service level, and social and/or economic impact.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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1.3 SCOPE
The development of the twenty-year CIP for Lily Pond’s Water Treatment Plant is based on facility plans and Tetra
Tech’s experience with master plans and condition assessment planning. The following work is included as part of
this capital improvement plan:
1. Estimation of effective capacities of unit process, equipment, and facilities based on population projections
for Cohasset’s service area,
2. Development of condition assessment of existing assets, including process, electrical, SCADA and
instrumentation, structural, architectural, HVAC, and site civil assets.
3. Evaluation and selection of projects based on prioritization ranking.
4. Opinion of probable construction cost of each capital improvement project in 2021 dollars.
5. Preparation of the CIP report, listing the recommended projects by funding in a 5-year incremental period.
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2.0 WATER QUALITY AND ENVIRONMENTAL REGULATORY COMPLIANCE REVIEW
2.1 RAW AND FINISHED WATER QUALITY REVIEW
A review of the historical raw and finished water quality was performed based on data from the following sources:
1. The MassDEP Drinking Water Program’s Water Quality Database from 1/1/2000 through 9/29/2020
2. The Town’s Daily Water Quality Sample Data from 6/1/2018 through 6/30/2020
3. The Town’s 2019 Water Quality Report
4. Pilot Test Report MIEX® DOC Resin Treatment (Weston & Sampson, November, 2006)
5. Pilot Test Report Ozone/BAC Treatment (Weston & Sampson, November, 2006)
A summary of the raw and finished water quality data is presented in Table 2-1. For the Lily Pond WTP raw and
finished waters, a corresponding time-series graphs of the total organic carbon (TOC), turbidity, manganese, and
iron levels are presented in Figures 2-1, 2-2, 2-3, and 2-4, respectively.
Overall, the Lily Pond surface water supply is a low alkalinity, organic-laden water with neutral pH, moderate total
dissolved solids (TDS), and low hardness based on raw and finished water qualities. The raw water TOC levels
have ranged from 4 mg/L to upwards of 16 mg/L with an average of 9.6 mg/L. Turbidity is generally moderate with
an average of about 2.0 NTU with the potential for occasional spikes in raw water turbidity as shown in Figure 3-2.
Relatively large fluctuations in the raw water manganese levels have also been observed. On average, manganese
levels are around 0.24 mg/L and has been measured at levels of up to 1.52 mg/L. These levels are well above the
secondary maximum contaminant level (MCL) for manganese of 0.05 mg/L; and therefore, require treatment.
Similarly, raw water iron levels are approximately 0.77 mg/L, on average, and have been seen to range up to 2.56
mg/L. At these levels, treatment for reducing iron is also needed for meeting the secondary MCL of 0.3 mg/L.
Based on the time series representation of the TOC data, a general seasonal variation can be observed, where the
TOC tends to be more elevated during the summer months (June through August) and lower during the winter and
springs months (December through April). TOC levels during fall months appeared to fluctuate from relatively low
to high. During the summer months, the raw water quality also tends to have higher levels of turbidity, color,
manganese and iron as revealed in Figures 2-2, 2-3, and 2-4.
Although TOC is not a directly regulated water quality parameter, its presence in the water supply results in the
increased potential for the formation of regulated disinfection byproducts (DBPs), namely total trihalomethanes
(TTHMs) and haloacetic acids (HAAs). As such, the Lily Pond WTP is required by MassDEP to demonstrate
compliance with Treatment Technique efficiency requirements of removing at least 50% of the raw water TOC. To
compensate for raw water quality variations, the Town’s operations team adjusts the coagulants and polymer
dosages when higher levels of turbidity, color, and TOC are detected in the raw water. As supported by the data,
operations adjustments serves to effectively treat the raw water turbidity by achieving a finished water turbidity of
0.11 NTU on average, thus removing approximately 94% of the turbidity on an average basis. Additionally, the
enhanced coagulation process achieves 50% removal of the TOC on average, which meets the Treatment
Technique efficiency requirements. The Town’s operations teams also adjusts the permanganate chemical dosing
for manganese and iron oxidation treatment and removal. As illustrated in Figure 2-4, the treatment process
achieves effective iron removal of 95%, on average. Overall, the treatment process is also effective in reducing the
manganese down to 0.07 mg/L, on average. However, the manganese treatment performance can be challenged
during the summer months, when raw water manganese levels have been shown to spike significantly. During the
summer, these elevated managanese levels are also accompanied by increased water demands and treatment
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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flows. The increased summer treatment flows likely contribute to a shorter mixing and contact time with the
permangatate oxidation and some diminishing of the treatment efficiency.
Table 2-1. Lily Pond WTP Raw and Finished Water Quality
Parameter Unit Lily Pond WTP
Raw Average
(Range)
Lily Pond WTP
Raw 95th
percentile
Lily Pond WTP
Finished
Average (Range)
Lily Pond WTP
Finished 95th
percentile
Temperature deg-C 15 (4 – 27.5) - 14 (6 – 26.4) 23.5
pH - 6.68 (0.68 – 9.57) 7.32 7.2 (6.36 – 8.51) 7.63
Alkalinity mg/L as
CaCO3 - - 11.0 -
Turbidity NTU 1.94 (0 – 14.8) 3.76 0.11 (0 – 1.58) 0.22
Total Dissolved
Solids
mg/L
- - 195 (180 – 210) 209
Hardness mg/L as
CaCO3 - - 27 (17 – 45) 45
Apparent Color PCU 130 (0 – 459) 264 1.77 (0 – 58.0) 8.0
True Color PCU 159 (88 – 324) - 1.6 -
UVA cm-1 0.57 (0.05 – 2.82) 1.08 0.05 (0 – 0.75) 0.08
TOC mg/L 9.6 (4 – 16) 13 3.2 (1.5 – 5.7) 4.6
DOC mg/L - - 2.3 -
Calcium mg/L - - 6.9 (3.6 – 13.5) 13.5
Iron mg/L 0.77 (ND – 2.56) 2.04 0.02 (ND – 1.00) 0.05
Copper mg/L - - 0.01 (ND – 0.021) -
Potassium mg/L - - 0.6 (ND – 1.2) 1.14
Sodium mg/L 36.8 (10 – 79) 74.3 43.5 (21.2 – 108) 75
Magnesium mg/L - - 2.3 (1.97 – 2.83) 2.8
Manganese mg/L 0.24 (ND – 1.52) 0.96 0.07 (ND – 1.04) 0.16
Chloride mg/L 43 (30 – 60) - 83 (79 – 87) 86.6
Fluoride mg/L 0.09 (ND – 0.96) 0.15 0.71 (0.05 – 6.73) 0.97
Sulfate mg/L 9.5 (6.4 – 15.3) - 21.4 (5.9 – 38.9) 35.8
Aluminum mg/L 0.04 (ND – 0.28) 0.15 0.004 (ND – 0.04) 0.02
Nitrate
- - 0.09 (0.05 – 0.23) 0.17
Phosphate mg/L PO4 - - 1.01 (ND – 2.42) 1.38
Odor TON - - 2.0 -
Chlorine, Free mg/L - - 1.27 (0.12 – 2.95) 1.78
Chlorine, Total mg/L - - 1.50 (0.67 – 3.23) 2.06
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1. ND = Non-detect.
Figure 2-1. Lily Pond WTP Raw and Finished Water TOC
0
2
4
6
8
10
12
14
16
18
2/17/2005 4/28/2007 7/6/2009 9/14/2011 11/22/2013 1/31/2016 4/10/2018 6/18/2020 8/27/2022Total Organic Carbon, TOC (mg/L)Lily Pond WTP Raw Lily Pond WTP Filter Effluent
Average Reduction = 66%
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Figure 2-2. Lily Pond WTP Raw and Finished Water Turbidity
Figure 2-3. Lily Pond WTP Raw and Finished Water Manganese
0
2
4
6
8
10
12
14
16
1-Jun-1818-Jun-185-Jul-1822-Jul-188-Aug-1825-Aug-1811-Sep-1828-Sep-1815-Oct-181-Nov-1818-Nov-185-Dec-1822-Dec-188-Jan-1925-Jan-1911-Feb-1928-Feb-1917-Mar-193-Apr-1920-Apr-197-May-1924-May-1910-Jun-1927-Jun-1914-Jul-1931-Jul-1917-Aug-193-Sep-1920-Sep-197-Oct-1924-Oct-1910-Nov-1927-Nov-1914-Dec-1931-Dec-1917-Jan-203-Feb-2020-Feb-208-Mar-2025-Mar-2011-Apr-2028-Apr-2015-May-201-Jun-2018-Jun-20Turbidity, NTURaw Water Finished Water
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
10-Apr-18 19-Jul-18 27-Oct-18 4-Feb-19 15-May-19 23-Aug-19 1-Dec-19 10-Mar-20 18-Jun-20 26-Sep-20Manganese (mg/L)Raw Water Finished Water
Average Reduction = 50%
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Figure 2-4. Lily Pond WTP Raw and Finished Water Iron
2.2 DISTRIBUTION SYSTEM DISINFECTION BYPRODUCTS REVIEW
A review of historical TTHM and HAA5 data was performed based on data from the MassDEP Drinking Water
Program’s Water Quality Database. The TTHM and HAA5 data was collected in accordance with the Stage 2 D/DBP
Rule from November 2013 to August 2020 at the following system compliance locations:
• 10202 – Deer Hill School, 208 Sohier Street, Cohasset, MA 02025
• 10204 – Police Station 62 Elm St., Cohasset, MA 02025
• 10205 – 2 Whitehead Road, Cohasset, MA 02025
• 10206 – 4 Beechwood Street, Cohasset, MA 02025
Times series representations of the TTHM and HAA5 results are provided in Figures 2-5 and 2-6, respectively. As
illustrated by the TTHM data in Figure 2-5, the TTHM results at the compliance locations within the Cohasset
distribution system have ranged from approximately 12 µg/L to 120 µg/L over the last seven years. Based on these
historical TTHM levels, single sample TTHM levels have been found to rise above the regulated MCL at the four
sampling locations during the summer and spring quarterly samplings. These TTHM results reveal an overall
seasonal variation in TTHM formation, where peaks in TTHM levels are typically observed during the summer
sampling events.
As shown in Figure 2-6, the corresponding HAA5 at the compliance locations have fluctuated from approximately
2 µg/L to 82 µg/L over the last seven years. The highest and second highest HAA5 levels (82 and 48.5 µg/L,
respectively) were measured at the 4 Beechwood Street location. The highest observed level fell above the 60 µg/L
level and is uncharacteristic based on the seven years of historical data. The second highest level is approximately
0.0
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Average Reduction = 95%
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81% of the 60 µg/L MCL. Unlike the TTHMs, the HAA5 data does not appear to exhibit a distinct seasonal pattern,
which suggest that the other mechanisms are influencing HAA5 levels in the distribution system. One of these
mechanisms, could be chlorine residual management to maintain adequate but generally lower residuals and an
accompanying biodegradation of HAAs within biofilms. Overall based on the full-scale data, the HAA5 formation
does not appear to be typically near regulatory levels, and therefore, appears to be effectively controlled by the
existing treatment and operation processes.
A closer review of the locational TTHM and HAA5 data was performed to compare the locational running annual
averages (LRAAs) to their respective MCLs. TTHM and HAA5 LRAA results for each compliance location are
presented in Figures 2-7 through 2-14. In each figure, the TTHMs and HAA5s results are represented as columns
and the corresponding LRAA is shown as a connected line. With the exception of the one Beechwood sample
collected in August 2019, the HAA5 levels are generally maintained below 80% of the 60 µg/L MCL. On the other
hand, individual TTHM results fell above the regulated MCL on two to seven occasions across the sampling
locations.
Although the corresponding LRAAs for each location have remained below the regulatory MCL due to the lower
seasonal TTHM levels, the LRAAs are approaching the 80 µg/L. Consequently, the Town has been considering
alternative DBP precursor treatment alternatives for further reducing and controlling DBP formation in the
distribution system. As part of this effort, the Town with the assistance of Tetra Tech recently completed the pilot
testing of granular activated carbon (GAC) downstream of filtration for to evaluate the treatment performance and
operational requirements. Further discussion of the future implications of DBP control is discussed in the following
Section 4.5.2 Future Water Quality Considerations.
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Figure 2-5. Cohasset Water Distribution System TTHMs
Figure 2-6. Cohasset Water Distribution System HAA5
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10/1/2013 2/13/2015 6/27/2016 11/9/2017 3/24/2019 8/5/2020Total Trihalomethanes (µg/L)10202-Deer Hill School 10204-Police Station 10205-2 Whitehead 10206-4 Beechwood TTHM MCL
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Figure 2-7. Deer High School Location TTHMs
Figure 2-8. Deer High School Location HAA5s
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Figure 2-9. Police Station Location TTHMs
Figure 2-10. Police Station Location HAA5s
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Figure 2-11. 2 Whitehead Location TTHMs
Figure 2-12. 2 Whitehead Location HAA5s
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Figure 2-13. 4 Beechwood Location TTHMs
Figure 2-14. 4 Beechwood Location HAA5s
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2.3 ENVIRONMENTAL REGULATORY COMPLIANCE REVIEW
2.3.1 United States Environmental Protection Agency
The Safe Drinking Water Act (SDWA) was passed by Congress in 1974 (Public Law 93-523)
to protect public health by regulating the nation’s drinking water supply. The law was
amended in 1986 and 1996 and requires many actions to protect drinking water and its
sources including rivers, lakes, reservoirs and ground water wells. In 1996, Congress
amended the SDWA to emphasize sound science and risk-based standard setting, small
water supply system flexibility and technical assistance, community-empowered source water
assessment and protection, public right-to-know, and water system infrastructure assistance
through a multi-billion-dollar state revolving loan fund. The SDWA sets national health-based
standards for drinking water for protection against both naturally occurring and man-made
contaminants that may be found in drinking water.
Under the SDWA, EPA sets legal limits on the levels of certain contaminants in drinking water. The legal limits
reflect both the level that protects human health and the level that water systems can achieve using the best
available technology. Besides prescribing these legal limits, EPA rules set water-testing schedules and methods
that water systems must follow. The rules also list acceptable techniques for treating contaminated water. SDWA
gives individual states the opportunity to set and enforce their own drinking water standards if the standards are at
least as strong as EPA's national standards. Massachusetts, like most states directly oversees the water systems
within the state.
2.3.1.1 Primary and Secondary Drinking Water Standards
The SDWA requires EPA to establish National Primary Drinking Water Regulations (NPDWRs) for contaminants
that may cause adverse public health effects. The regulations include both mandatory maximum contaminant levels
and non-enforceable health goals for each contaminant. The non-enforceable health goals, based solely on possible
health risks and exposure over a lifetime with an adequate margin of safety, are called maximum contaminant level
goals (MCLG). Contaminants are any physical, chemical, biological or radiological substances or matter in water.
Maximum contaminant levels (MCLs) are set as close to the health goals as possible, considering cost, benefits
and the ability of public water systems to detect and remove contaminants using suitable treatment technologies.
MCLs have additional significance because they can be used under the Superfund Law as "Applicable or Relevant
and Appropriate Requirements" in cleanups of contaminated sites on the National Priorities List.
EPA has also set secondary standards which are non-enforceable guidelines regulating contaminants that may
cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in
drinking water. EPA recommends secondary standards to water systems but does not require systems to comply.
However, states may choose to adopt them as enforceable standards. Future NPDWR standards will apply to non-
transient non-community water systems because of concern for the long-term exposure of a stable population.
In addition to the federal primary and secondary drinking water standards, the EPA has also promulgated several
rules that set standards, water-testing schedules, and methods pertaining to chemical contaminants, microbial
contaminants, and right-to-know procedures that water systems must follow. Of these, rules relevant to the Lily
Pond WTP include the Arsenic Rule, Chemical Contaminant Rules, Lead and Copper Rule, Radionuclides Rule,
Disinfectant/Disinfection Byproducts Rule, Surface Water Treatment Rules, Total Coliform Rule, Consumer
Confidence Report Rule, and Public Notification Rule.
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2.3.1.1 Arsenic Rule
On January 22, 2001 EPA adopted a lower standard for arsenic in drinking water at 10 parts per billion (ppb),
replacing the old standard of 50 ppb. The rule became effective on February 22, 2002. The date by which systems
must comply with the new 10 ppb standard was January 23, 2006.
2.3.1.2 Chemical Contaminant Rules
The Chemical Contaminants were regulated in phases, which are collectively referred to as the Phase II/V Rules or
the Chemical Contaminant Rules. These rules regulate over 65 contaminants in three contaminant groups:
Inorganic Contaminants (IOCs) that include nitrate and arsenic, Volatile Organic Contaminants (VOCs), and
Synthetic Organic Contaminants (SOCs). The rules apply to public water systems (PWS). PWS type, size, and
water source determine which contaminants require monitoring for that system.
2.3.1.3 Lead and Copper Rule
In older homes and buildings, lead and copper can leach from service lines, solder, and fixtures into tap water and
become a significant source of lead and copper exposure. Exposure to lead and copper may cause health problems
ranging from stomach distress to brain damage. In children, lead exposure in particular can cause irreversible and
life-long health effects, including decreasing IQ, focus, and academic achievement. On December 22, 2020, EPA
finalized the New Lead and Copper Rule (LCR). The new LCR is the first major update to the rule in nearly 30 years.
The new LCR strengthens regulatory requirements to better protect children and communities from the risks of lead
exposure.
The new LCR maintains the lead and copper action levels (ALs) at 15 µg/L and 1.3 mg/L, respectively, for the 90th
percentile of samples collected at customers’ taps. If lead concentrations exceed the action level of 15 ppb or copper
concentrations exceed the action level of 1.3 ppm in more than 10% of customer taps sampled, the system must
undertake a number of additional actions that have been expanded from the original rule. Additionally, the new rule
sets a lead trigger level of greater than 10 and less than or equal to 15 µg/L for the 90th percentile of samples. 90th
percentile lead results within the trigger level will trigger additional planning, monitoring, and treatment
requirements.
A summary of additional key updates to the rule is provided as follows:
• Lead and Copper Tap Monitoring
o Prioritizes collecting samples from sites served by lead service lines.
o Requires new, improved tap sampling procedures.
o Lead monitoring schedule is based on the 90th Percentile level
90th Percentile > 15 µg/L: Semi-annually at the standard number of sites
90th Percentile > 10 to 15 µg/L: Annually at the standard number of sites
90th Percentile ≤ 10 µg/L: Annually and triennially at reduced number of sites using same
criteria of original rule
o Copper follows the same criteria as current rule and samples can be analyzed for lead only when
monitoring is conducted more frequently than copper.
• Corrosion Control Treatment and Water Quality Parameters
o Specifies corrosion control treatment for systems with 90th Percentile results > 10 to 15 µg/L.
o Systems with 90th Percentile results > 15 µg/L must install or re-optimize corrosion control
treatment.
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o Small systems (≤10,000 people) with 90th Percentile results > 10 µg/L can select approach to
address lead with Primacy Agency approval, including corrosion control treatment, lead service line
replacement, provision and maintenance of point-of-use devices, or replace all lead-bearing
plumbing materials
o Calcium hardness adjustment is no longer an acceptable corrosion control option.
o Specifies that phosphate inhibitor must be orthophosphate.
o Eliminates water quality parameters related to calcium hardness.
o To qualify for reduced water quality parameter distribution monitoring, the 90th percentile for lead
must be 10 µg/L or less and the system must meet its optimal water quality parameters.
o Corrosion control treatment and water quality parameter data must be reviewed during sanitary
surveys against the most recent treatment guidance issued by EPA.
• Lead Service Line Inventory and Lead Service Line Replacement Plan
o All systems must develop a lead service line inventory or demonstrate absence of lead service
lines within first three (3) years of final rule publication.
o Rule specifies lead service line replacement programs based on the 90th percentile level for
systems serving greater than 3,300 people.
• Source Water Monitoring and Treatment
o Systems must obtain prior Primacy Agency approval before changing source or treatment.
• Lead in Drinking Water at Schools and Child Care Facilities
o Systems must conduct lead sampling at 20% of elementary schools and 20% of child care facilities
per year and conduct sampling at secondary schools on request for 1 testing cycle (5 years) and
conduct sampling on request of all schools and child care facilities thereafter.
o Sample results and public education must be provided to each sampled school or child care facility.
o Excludes facilities build or replaced all plumbing after January 1, 2014.
2.3.1.4 Radionuclides Rule
In 2000, EPA revised the radionuclides regulation to reduce the exposure to radionuclides in drinking water. The
new rule revisions set new monitoring requirements for community water systems for meeting the MCLs for
radionuclides in drinking water. Additionally, EPA issued a standard for uranium. The current standards are:
• Combined radium 226/228 of 5 pCi/L
• Gross alpha standard of 15 pCi/L (not including radon and uranium)
• Beta emitters combined standard of 4 mrem/year
• Uranium standard of 30 µg/L
2.3.1.5 Disinfectants and Disinfection Byproducts Rule
The Stage 1 Disinfectants and Disinfection Byproducts Rule (Stage 1 DBPR) was finalized in December 1998 and
strengthens control of chemical disinfectants and their potentially cancer-causing byproducts, in drinking water.
The Stage 1 DBPR applied to systems of all sizes that use chemical disinfectant for primary or residual treatment.
It was developed as part of a group of standards that address the risk trade-offs between microbiological
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contaminants and disinfection byproducts. These rules, collectively called the microbial and disinfection byproducts
rules, are the first to address the waterborne pathogen, Cryptosporidium, in drinking water.
The Stage 1 DBPR applied to community water systems and non-transient non-community systems that add a
disinfectant to the drinking water during any part of the treatment process, including those serving fewer than 10,000
people. For systems that serve more than 10,000 customers, the rule took effect on January 1, 2002. For systems
that serve fewer than 10,000 customers, the rule took effect on January 1, 2004. The Stage 1 DBPR established
seven new standards and a treatment technique of enhanced coagulation and enhanced softening to further reduce
DBP exposure in systems using surface water or groundwater under the influence of surface water. The standard
applies to all systems that add chlorine, chloramines, or chlorine dioxide as a disinfectant.
The rule established maximum residual disinfectant levels (MRDLs) for chlorine (4 mg/L), chloramines (4 mg/L),
and chlorine dioxide (0.8 mg/L). MRDLs are similar to MCLs but are applicable to disinfectants. The MRDLs keep
disinfectant levels low enough to minimize disinfection byproduct (DBP) formation and limit adverse health effects.
The rule specifies MCLs for four trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, and
bromoform). MCLs for total trihalomethanes (the sum of the four listed above) cannot exceed 0.080 mg/L. The rule
sets MCLs for haloacetic acids: dichloroacetic acid, and trichloroacetic acid. The sum of the above total haloacetic
acids plus monochloroacetic acid, mono and dibromoacetic acids must fall below 0.060 mg/L.
MCLs are also established for two inorganic disinfection byproducts: chlorite (1.0 mg/L) and bromate (0.010 mg/L)
and the treatment technique of enhanced coagulation and lime softening for removal of natural organic matter is
required. The Stage 1 rule required a monitoring plan that outlined schedules for collecting DBP samples and at
which locations. Compliance was based on a running annual average (RAA) of samples from all locations across
the system.
The Stage 2 DBPR builds upon the Stage 1 DBPR to address higher risk public water systems for protection
measures beyond those required for existing regulations. The Stage 2 DBPR and the Long Term 2 Enhanced
Surface Water Treatment Rule (LT2) are the second phase of rules required by Congress. These rules strengthen
protection against microbial contaminants, especially Cryptosporidium, and at the same time, reduce potential
health risks of DBPs.
The Stage 2 DBPR supplements the Stage 1 DBPR and requires water systems to meet disinfection MCLs at each
monitoring site in the distribution system. The rule also seeks to better identify monitoring sites that include pockets
where high concentration of DBPs are suspected. The Stage 2 DBP rule focuses on public health protection by
limiting exposure to DBPs, specifically total trihalomethanes (TTHM) and five haloacetic acids (HAA5), which can
form in water through disinfectants used to control microbial pathogens. This rule applies to all community water
systems and non-transient non-community water systems that add a primary or residual disinfectant other than
ultraviolet (UV) light or deliver water that has been disinfected by a primary or residual disinfectant other than UV.
The Stage 2 DBPR requires that systems do a self-assessment and identify locations within a distribution system
that have higher residence time of liquid sitting stagnant (pockets). Samples have to be taken at these sites. Under
the Stage 2 DBPR, maximum contaminant levels of TTHM and HAA5s will be measured or calculated at each
monitoring site. A locational running annual average (LRAA) or running yearly average of each sample collected
at the specified location will be calculated. Compliance is based on a LRAA. Any LRAA that exceeds the MRDL is
considered a violation.
2.3.1.6 Surface Water Treatment Rules
The Surface Water Treatment Rule (SWTR) and its counterparts – the Interim, Long Term 1, and Long Term 2
Enhanced SWTRs – aim to control microbial contaminants. Surface water treatment facilities must remove a
minimum of 99 percent (2-log) of Cryptosporidium, 99.9 percent (3-log) of Giardia lamblia cysts, and 99.99 percent
(4-log) of viruses by filtration and disinfection. In addition, treatment facilities must maintain filtered water turbidities
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within 0.3 NTU (1 NTU maximum) and disinfectant residual levels above at least 0.2 mg/L. Microbial control is also
addressed by the Filter Backwash Recycling Rule (FBRR). The FBRR requires treatment systems that recycle filter
backwash wastewater to return the recycle stream to the headworks of the existing treatment system. A summary
of the suite of SWTRs is provided in Table 2-2.
2.3.1.7 Total Coliform Rule
The Total Coliform Rule, which was published in 1989, set both health goals (Maximum Contaminant Level Goals)
and legal limits (Maximum Contaminant Levels) for the presence of total coliforms in drinking water. The rule also
details the type and frequency of testing that water systems must undertake. The rule applies to all public water
systems.
Table 2-2. Surface Water Treatment Rules
Promulgation Date Regulation
June 29, 1989 Surface Water Treatment Rule
December 16, 1998 Interim Enhanced Surface Water Treatment Rule
June 8, 2001 Filter Backwash Recycling Rule
January 4, 2002 Long Term 1 Enhanced Surface Water Treatment Rule
January 5, 2006 Long Term 2 Enhanced Surface Water Treatment Rule
EPA revised the 1989 Total Coliform Rule on February 13, 2013, to improve public health protection and the
implementation of the rule by States and public water systems. Public water systems and primacy agencies must
comply with the requirements of the Revised Total Coliform Rule (RTCR) by April 1, 2016. Until then, PWSs and
primacy agencies must continue complying with the 1989 Total Coliform Rule. Revisions related to RTCR include
establishment of an MCL for E. coli, violations of the rule are based on E. coli only, and assessment and corrective
action is required based on the monitoring results.
2.3.1.8 Consumer Confidence Report Rule
The Consumer Confidence Report (CCR) Rule was published in 1998 and establishes the minimum requirements
for the content of annual reports that community water systems must deliver to their customers. These reports must
contain information on the quality of the water delivered by the systems and characterize the risk (if any) from
exposure to contaminants detected in the drinking water in an accurate and understandable manner. The CCR Rule
was included in EPA’s Final Plan for Periodic Retrospective Reviews of Existing Regulations in 2011. The
Retrospective Review was completed in 2012 and covered the following five areas:
CCR understandability;
Reporting MCLs in numbers greater than or equal to 1.0;
Reporting period for including a Tier 3 Public Notice in the CCR:
The certification of CCR delivery and content by the community water system to the primacy agency; and
Electronic delivery of the CCR.
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2.3.1.9 Public Notification Rule
The Public Notification Rule is part of the SDWA to ensure that consumers know if there is a problem with their
drinking water. These notices alert consumers if there is a risk to public health and if:
a. The water does not meet drinking water standards;
b. The water system fails to test its water;
c. The system has been granted a variance (use of less costly technology); or
d. The system has been granted an exemption (more time to comply with a new regulation).
2.3.1.10 America’s Water Infrastructure Act of 2018 (AWIA) Title II
As a response to September 11, 2001, the Bioterrorism Act of 2002 drove the need to implement Vulnerability
Assessments and Emergency Response Plans in the early 2000s. Recently, On October 23, 2018, EPA enacted
into law America’s Water Infrastructure Act (AWIA) of 2018 (S.3021; Law No. 115-270). Title II of the Act pertains
to “Community Water System Risk and Resilience” and mandates that water systems identify “risk from malevolent
and natural hazards, and the operation and maintenance of the system to include strategies and resources to
improve the resilience of the system, including physical security and cybersecurity”.
In summary, AWIA requires water systems serving more than 3,300 people to develop or update Risk and
Resilience Assessments and emergency response plans (ERPs). The law specifies the components that the risk
assessments and ERPs must address and establishes deadlines by which water systems must certify to EPA
completion of the risk assessment and ERP.
An overview of the components required for preparing the Risk and Resiliency Assessment and Emergency
Response Plan is provided as follows:
Risk and Resiliency Assessment
• Asset characterization (physical, human, cyber)
• Threat characterization (malevolent acts, natural hazards, dependency hazards)
• Consequence, vulnerability, and threat analysis
• Specifically address:
o Source water
o O&M practices
o Chemical use, storage, and handling
o Financial infrastructure
• Submit certification letter to EPA
Emergency Response Plan (ERP)
• Prepare the ERP
a. System overview
b. Established roles and responsibilities
c. Internal and external communications
d. Mutual aid and partnership (NIMS ICS, WARN)
e. Training
f. Documentation practices
g. Mitigation to address hazards
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• Submit certification letter to EPA
Community water systems will need to submit certification letters to the EPA based on population served. Both Risk
and Resilience Assessment and ERP certifications must be re-certified every five (5) years. A summary of the
compliance dates by utility size is presented in Table 3-3. Non-compliance can result in penalties of $25,000 per
day. Additional information and resources for preparing the Risk and Resilience Assessment and Emergency
Response Plan are available on EPA’s website: https://www.epa.gov/waterresilience/americas-water-
infrastructure-act-risk-assessments-and-emergency-response-plans.
Based on the Town’s current population of less than 10,000, compliance deadlines for submitting the Risk &
Resiliency Assessment Compliance and ERP Compliance Letters are June 30, 2021 and December 31, 2021,
respectively.
Table 2-3. America’s Water Infrastructure Act (AWIA) of 2018 Compliance Summary
Utility Size
(Population Served)
Risk & Resilience Assessment
Compliance Letter
Emergency Response Plan
Compliance Letter
>100,000 March 31, 2020 September 30, 2020
50,000 - 100,000 December 31, 2020 June 30, 2021
3,300 - 50,000 June 30, 2021 December 31, 2021
2.3.2 Massachusetts Department of Environmental Protection
2.3.2.1 Drinking Water Standards and Guidelines
Under the SDWA, a state may be granted primacy for implementing the provisions of the SDWA. The
Massachusetts Department of Environmental Protection (MassDEP) has primacy for implementation.
As part of that primacy, Mass DEP is responsible for ensuring the quality of Massachusetts public
drinking waters and enforcing the SDWA within the state. Generally, the state adopts the national
primary and secondary drinking water standards of the federal government and creates additional
rules to fulfill state requirements.
MassDEP sets standards and guidance levels for various contaminants as listed in the drinking water regulations
(310 CMR 22.00). In addition to the drinking water standards, MassDEP has derived Immediate Action Levels for
routinely used water treatment chemicals, to enable water treatment plant operators to identify and address serious
incidents of chemical overfeed or misuse. The following five primary types of guidance are available for assessing
drinking water quality in Massachusetts:
1. Massachusetts Maximum Contaminant Levels (MMCLs)
2. MassDEP Office of Research and Standards (ORS) Guidelines
3. Secondary Maximum Contaminant Levels
4. US PEA Health Advisories
5. USEPA
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The MMCLs are outlined in the drinking water regulations (310 CMR 22.00) and consist of promulgated EPA MCLs
and additional MCLs set specifically by Massachusetts. A summary of the current MMCLs is included in Tables
A-1, A-2, and A-3 of Appendix A. The standards are enforced by the Drinking Water Program. In addition to the
MMCLs, MassDEP Office of Research and Standards (ORS) issues guidance for chemicals other than those
included in the MMCLs based on EPA IRIS toxicity values, EPA Health Advisories, promulgated but not yet effective
EPA standards, or review and evaluation of available data for the chemical of interest. These ORS guidance values
are known as ORS Guidelines or ORSG and are usually developed for use by MassDEP programs in the absence
of other federal standards or guidance. A list of the current ORS Guidelines is provided in Table A-4 of Appendix
A.
MassDEP also has guidance values for secondary maximum contaminant levels (SMCLs). These SMCLs are based
on EPA secondary standards representing levels of chemicals or parameters above which the aesthetic properties
of the water can be affected (taste, odor, color), or cosmetic effects may occur (skin or tooth discoloration). The
SMCLs are summarized in Table A-5 of Appendix A.
The EPA provides drinking water guidance in the form of Health Advisories for different durations of exposure (i.e.,
one-day, ten-day and lifetime). These are based upon non-cancer health effects. They are used by MassDEP when
evaluating the potential health risks from chemicals in drinking water when no MMCL or ORSG is available.
An overview of the key drinking water standard, guidelines, and requirements that are outlined in MassDEP’s 310
CMR 22.00 regulations is provided as follows:
Section 22.00. “Drinking Water,” adopts EPA rules and regulates the water produced by public water systems
and covers the following criteria: MCL applied to finished drinking water, monitoring
requirements and frequencies, surveillance, record keeping, and reporting requirements.
Section 22.03. “Compliance” defines the requirements that water suppliers must meet to provide safe drinking
water. This section also describes the actions a water system must take when it is out of
compliance with the established standards and defines the prohibited acts that are considered
violations of the MassDEP regulations.
Section 22.04. “Construction, Operation, and Maintenance of Public Water Systems,” establishes the
requirements for construction and operation and maintenance of a public water system. Section
22.04 includes information required for permitting new construction and guidelines to modify
existing treatment plants.
Section 22.05. “Maximum Microbiological Contaminant Levels, Monitoring Requirements, and Analytical
Methods”, establishes and describes the requirements for routine coliform monitoring, including
sampling plan, monitoring frequency, monitoring requirements, E. coli requirements, treatment
techniques, analytical methods, and MCLs.
Section 22.06. “Inorganic Chemical Maximum Contaminant Levels, Monitoring Requirements, and Analytical
Methods,” establishes and describes the requirements for inorganic chemicals, including
monitoring sampling and frequency, and reporting, MCLs, sampling protocol, and analytical
methods.
Section 22.06B. “Control of Lead and Copper in Drinking Water,” describes treatment techniques, including
corrosion control treatment and source water treatment, along with monitoring and reporting
requirements.
Section 22.07D. “Secondary Chemicals Standards,” describes the secondary contaminants and levels,
monitoring requirements, exceeding levels, and analytical methods.
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Section 22.07E. “Disinfection Byproducts, Disinfection Residuals, and Disinfection Byproduct Precursors,”
summarizes disinfection byproducts and disinfectant’s regulations in the distribution system,
approved methods for compliance monitoring, and reporting and recordkeeping requirements.
Section 22.07F. “Stage 2 Disinfection Byproducts Requirements (DBPR)”, establishes the monitoring and other
requirements for identifying Stage 2 DBPR compliance monitoring locations for determining
compliance with MCLs for total trihalomethanes (TTHMs) and haloacetic acids (five) (HAA5).
Section 22.07G. “Per- and Polyfluoroalkyl Substances (PFAS) Monitoring and Analytical Requirements,”
indicates the newly established maximum contaminant level of 20 nanograms per liter (ng/L) for
the sum of six specific PFAS and the newly approved PFAS analyzing method. This section
also specifies monitoring protocols and frequency, and PFAS detection and reporting
requirements.
Section 22.19. “Distribution System Requirements,” establishes and describes the requirements for protecting
the distribution system of a public water system from contamination. This section includes
requirements for water storage tanks, storage reservoirs, construction materials evaluation,
identification and reporting of materials of construction, and record keeping.
Section 22.20A-G. “Surface Water Treatment Rules,” establishes Treatment Technique, filtration, disinfection,
sampling and monitoring, backwash recycle, and reporting requirements for public water
systems supplied by surface water sources and groundwater under the direct influence of
surface water.
2.3.2.2 Per- and Polyfluoroalkyl Substances (PFAS)
On October 2, 2020, MassDEP established an MCL of 20 ng/L for the sum of six PFAS compounds—PFOS, PFOA,
PFHxS, PFNA, PFHpA, and PFDA, known collectively as PFAS6. The intent of this new amendment to the
MassDEP drinking water regulations is to increase public health protection through the reduction of chemicals that
have been linked to a variety of health risks, particularly for sensitive subgroups including pregnant women, nursing
mothers, and infants.
Small community systems serving 10,000 or fewer people will be required to begin regulatory compliance on
October 1, 2021. The PFAS6 sampling requirements are summarized in Table 3-4. If there is a PFAS6 detection,
and the average of detection and confirmatory sample exceeds the MCL, the PWS needs to provide public
education materials regarding the exceedance within 30 days. Compliance is based on calculating the average of
the monthly samples over a quarter. If any sample results from any one sampling location would cause the quarterly
average to exceed the PFAS6 MCL, then the PWS is in violation. A violation requires a Tier 2 Public Notice. Any
monitoring and testing procedure violations require Tier 3 Public Notice.
In response to the new PFAS6 standard, the Town has proactively started sampling and monitoring for PFAS6 in
their water supplies. A review of the preliminary PFAS6 results for the Lily Pond WTP is included in Section 4.4.
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Table 2-4. PFAS6 Sampling Requirements Summary
Sampling
Locations
Initial Monitoring
(First Year)
Routine Monitoring Confirmatory
Sampling
Increased
Monitoring
1. Every entry
point to the
distribution
system
2. Four
consecutive
quarterly
samples must
be collected in
the initial first
year of
sampling
3. If initial monitoring
does not identify
any PFAS6, a
PWS may monitor
during one year of
each subsequent
three-year
Compliance
Period
4. 2 quarterly
samples required
in that sampling
year
5. Detection of
PFAS during
initial
monitoring
triggers
confirmation
sampling
6. PFAS6
detection
> 10 ng/L
triggers
confirmation
sampling
7. Confirmatory
sampling is not
required if
MassDEP
determines the
location is
Reliably and
Consistently
below the MCL
8. If the average
PFAS6 > 10 ppt,
the sampling
location must be
sampled monthly
and continued
until the source
is consistently
below the MCL
9. Quarterly
monitoring is
required where
PFAS treatment
is installed
10. Annual
monitoring for
PFAS6 < 10 ng/L
or consistently
below the MCL
2.3.2.3 Design, Permitting, and Construction
Design and construction of water treatment facilities are regulated by the MassDEP in accordance with 310 CMR
22.00 and MassDEP’s Guidelines for Public Water Systems. Before construction or alteration, of any existing or
future water plant, the Town would need to prepare and submit an application using MassDEP’s Form WS 24. The
application will need to be executed in full and submitted to the MassDEP with the following:
• Cover letter explaining the request.
• Comprehensive report describing the project, basis of the design, and requirements of MassDEP’s
Guidelines for Public Water Systems.
• One hard copy and one electronic copy of the detailed plans and specifications for the project.
• Transmittal Form for Permit Application and Payment.
• The non-refundable fee required by the application.
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The following provides a general overview of the MassDEP design requirements for permitting the water treatment
facilities:
Water Treatment Plant Facilities
The FDEP mandates several requirements as to the location and general design of water treatment plant facilities,
which in this case includes chlorination, fluoridation, ground storage, high service pumping, flow metering, coatings,
materials of construction, and color coding/pipe identification.
Disinfection
The Surface Water Treatment Rules require utility providers that utilize surface water as their source of potable
water supply to provide 4-log virus treatment, 3-log Giardia Lamblia treatment, and 2-log Cryptosporidium. Public
water systems must also maintain a disinfectant residual in the distribution system which must be monitored
continuously.
2.3.2.4 Staffing
Community water systems are required by the MassDEP to have licensed operators. The staffing requirements for
drinking water facilities are described in 310 CMR 22.11B and are based on treatment facilities and distribution
system classification. The overall system, from raw water source to finished water distribution, is rated according to
MassDEP’s specified treatment unit rating values. The increasing numerical class indicates an increasing
complexity of operation and a higher level of training, knowledge, and experience required for operation.
MassDEP requires water facilities and their distribution systems to be operated at all times by a Primary Operator
and a Secondary Operator. A Primary Operator is a certified operator who has a grade certificate equal to the class
of the treatment facility and a Secondary Operator is a certified operator who has a grade certificate not less than
one grade lower than the classification of the treatment facility. The classification of treatment facilities is established
by adding together the rating values reflecting the complexity of operation of the facility’s treatment units as outlined
in 310 CMR 22.11B’s Treatment Unit Rating Values Table. There are four (4) treatment facility classes based on
the following points system:
1. Class I-T 30 Points and less
2. Class II-T 31 to 55 Points
3. Class III-T 56 to 75 Points
4. Class IV-T 76 Points and greater
The Lily Pond WTP is classified as Class IV-T. Based on the plant capacity, the plant requires staffing by at least
a Class IV-T primary operator and at least a Class III-T secondary operator. The primary operator is required to be
present at the plant at least one (1) seven-hour working shift each day for five days during each work week (7
consecutive days) and needs to be available to respond in person to emergencies within one hour at times not
present at the facility. The secondary operator is required to be present at the plant on working shifts when the
primary operator is not required to be present and when the primary operator is absent.
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2.3.2.5 Monitoring Requirements
Table 2-5 presents the monitoring required by MassDEP for compliance with permits.
Table 2-5. Monitoring Requirements
Monitoring & Report Due Comments
Microbiological (Bacteria) Monthly Eight (8) samples per month for population served
between 6,701 and 7.600.
Disinfectant Residual Reports Monthly Eight (8) samples per month.
Inorganic Compounds (including
Nitrate and Nitrite) 2021 Sample at POE* at least once (1) per year.
Fluoride Monthly Sample at POE monthly.
Volatile Organic Contaminants 2020 Sample at POE every 3 years.
Synthetic Organic Contaminants 2 Quarters 2020 Non-vulnerable source may be granted a waiver.
Turbidity Monthly Sample filtered water daily.
Secondaries 2021 Sample at POE yearly (recommended).
Radionuclides 2022 Sample every 3 years which can be reduced to
once every six or nine years (310 CMR 22.09A 2C)
Stage 2 Disinfection Byproducts and
Disinfection Byproduct Reports Quarterly Quarterly testing at 4 sites for both TTHMs/HAA5
(dual samples).
Lead and Copper (Tap Sampling) 2022 At least 20 samples every 3 years.
Monthly Operation Reports (MORs) Monthly
Include information and reports for Filtered
Systems, CT calculations, Turbidity, Chemical
Addition, DBPR Treatment Technique, Total
Organic Carbon, Chlorine, and maintenance and/or
abnormal occurrences.
Consumer Confidence Report &
CCR Certification of Delivery
July 1 of each
year
*POE = Point of entry to the distribution system. Sample at each POE that is representative of source after treatment.
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2.4 FUTURE REGULATORY CONSIDERATIONS
2.4.1 Contaminant Candidate List
The SDWA amendments of 1996 set forth a cyclical process for EPA to identify "candidate" contaminants for
possible regulation and then determine whether any meet SDWA requirements for being regulated. Collectively,
this is referred to as the CCL/Regulatory Determination process. The Contaminant Candidate List is the starting
point for EPA’s regulatory development process for new contaminants. The Safe Drinking Water Act requires the
EPA to develop a list of potential contaminants to consider for regulation on every five years. EPA has published
four (4) CCLs: CCL1 in 1998 – 60 contaminants; CCL2 in 2005 – 51 contaminants; CCL3 in 2009 – 116
contaminants, and CCL4 in 2016 – 109 contaminants. The CCLs are lists of contaminants that are currently not
subject to any proposed or promulgated national primary drinking water regulations but are known or anticipated to
occur in public water systems. Contaminants listed on the CCLs may require future regulation under the SDWA.
On January 2021, EPA announced final regulatory determinations for contaminants on the CCL4. EPA is making
final determinations to regulate two contaminants—PFOS and PFOA, in drinking water and to not regulate six
contaminants—1,1-dichloroethane, acetochlor, methyl bromide (bromomethane), metolachlor, nitrobenzene, and
RDX. EPA will initiate the process to develop a National Primary Drinking Water Regulation for PFOS and PFOA,
which will include further analyses, scientific review, and opportunity for public comment. As reviewed previously,
MassDEP has recently regulated these PFAS substances ahead of national regulations because of their severe
potential health effects, particularly for vulnerable populations.
EPA is beginning the development of the CCL5. The public was able to nominate contaminants by December 4,
2018. EPA is currently evaluating nominations and other contaminant data and information to publish a CCL5 for
public review and comment. The SDWA requires the EPA to publish the CCL every five years; therefore, CCL5 is
expected to be published in 2021.
2.4.2 Six-Year Review
EPA reviews existing regulations every six years to determine whether they still adequately protect public health,
given any new health effects information that may have become available. If revisions to a standard are warranted,
they can be made provided that no existing standard is revised in a way that reduces protection of public health.
In the first Six-Year Review of 2003, EPA reviewed 69 standards and decided to revise the Total Coliform Rule.
Compliance with the revised Total Coliform Rule is not required until 2016. In the second Six-Year Review of 2010,
EPA reviewed 71 standards and decided to revise four standards: trichloroethylene (TCE), tetrachloroethylene
(PCE), epichlorohydrin and acrylamide. The revised standards for TCE and PCE were incorporated into the
carcinogenic volatile organic chemicals group rule scheduled to be proposed. The timeframe for revising the
epichlorohydrin and acrylamide standards is unclear at this time. In December 2016, the Third Six-Year Review
was published which concluded that eight National Primary Drinking Water Regulations (NPDWRs) are candidates
for regulatory revision. These included: Chlorite, Cryptosporidium, Haloacetic acids, Heterotrophic Bacteria, Giardia
lamblia, Legionella, Total Trihalomethanes, and Viruses. The eight NPDWRs are included in the following rules:
• Stage 1 and Stage 2 Disinfectants and Disinfection Byproducts Rules,
• Surface Water Treatment Rule,
• Interim Enhanced Surface Water Treatment Rule, and
• Long Term 1 Enhanced Surface Water Treatment Rule.
EPA is currently requesting public comment on the eight NPDWRs identified as candidates for revision. EPA will
consider comments received in determining whether regulatory actions are necessary. There are no set revision
dates to the eight NPDWRs. EPA has begun the fourth Six-Year Review process by conducting the initial step for
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obtaining the necessary information to do a comprehensive review of the NPDWRs. On October 5, 2018, EPA
published the Federal Register Notice announcing the proposed information collection request for contaminant
occurrence data in support of the fourth Six-Year Review. The deadline for public comment was December 4, 2018.
On October 31, 2019, the information collection request was submitted for review and additional public comment
period and deadline of December 2, 2019 was announced. On June 3, 2020, EPA sent a request to primary
agencies for the voluntary submission of contaminant occurrence data and treatment technique information
collected from 2012 to 2019. The fourth Six-Year Review results are anticipated to be completed in early 2023.
2.4.3 Revised Aluminum Criteria in NPDES Permits
The EPA first released freshwater criteria for aluminum in 1988 to protect aquatic life from harmful effects of
aluminum toxicity. The existing criteria sets fixed values for aluminum of 750 μg/L acute and 87 μg/L chronic.
Recently in 2018, EPA released the final report updating the aquatic life criteria for aluminum in freshwater that
reflects the latest science on aluminum toxicity, which shows that pH, dissolved organic carbon (DOC), and
hardness can affect the bioavailability of aluminum in surface water (“2018 Final Aquatic Life Criteria for Aluminum
in Freshwater”). As a result, EPA is proposing revised aluminum criteria based on the Aluminum Criteria Calculator
that allows users to adjust the aluminum criteria to local conditions by entering site-specific values for pH, total
hardness, and DOC to calculate the appropriate recommended freshwater acute and chronic criteria magnitudes
using a multiple linear regression modelling approach (EPA, 2018). The calculator models the relationships between
water chemistry (pH, DOC, and harness) and aluminum toxicity to calculate the criteria as illustrated conceptually
in Figure 3-15.
Figure 2-15. EPA Aluminum Criteria Calculator Schematic
Based on EPA’s revised criteria, MassDEP is proposing the adoption of revised aluminum criteria into their 314
CMR 4.00: The Massachusetts Surface Water Quality Standards. The proposed rule revision adoption will be
implemented by setting new aluminum permit limits within National Pollutant Discharge Elimination System
(NPDES)/Surface Water Discharge Permits. The revised criteria will require the use of either the Aluminum Criteria
Calculator or watershed default criteria for determining permit limits. The requirements will depend on the availability
of chemistry data for the waterbody as summarized below:
• If appropriate chemistry data are available for the waterbody, the Aluminum Criteria Calculator will be used
to calculate site-dependent criteria using water chemistry inputs (pH, DOC, and hardness) and to determine
permit limits.
• If appropriate chemistry data are not available for the waterbody, watershed default criteria will be used for
determining permit limits.
Along with these revisions to the Surface Water Quality Standards, MassDEP will be publishing an aluminum
implementation guidance for the revised freshwater aluminum criteria in Spring/Summer 2021. The implementation
guideline will provide useful information on the scientific premise of the revised criteria, data requirements, and the
methodology used to calculate site-dependent criteria values. MassDEP recommends that facilities intending to
undertake monitoring for the revised criteria contact the department early for input and guidance throughout the
process. MassDEP will review and approve the procedures associated with monitoring, review reports to ensure
required information is provided, and calculate final site-dependent criteria values based on information provided in
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final reports. Only these final site-dependent aluminum criteria values will be used to determine permit effluent limits
for aluminum, if required.
In anticipation of these revisions, MassDEP partnered with the USGS in an Aluminum Monitoring Project. The
objectives of the project were to collect water quality data at 12 freshwater sites in Massachusetts; and use the
collected data to demonstrate a process for calculating aluminum criteria based on a site’s water chemistry using
the EPA Aluminum Criteria Calculator. The Town’s Lily Pond water supply was included in the aluminum sampling
and monitoring program. Preliminary results for Lily Pond from the monitoring project are presented in Table 2-6.
Table 2-6. USGS-MassDEP Aluminum Study (2018-2019) Preliminary Results
Facility Receiving
Water
Body
Existing Aluminum
Criteria (µg/L)
Proposed Watershed
Default Criteria Values
(µg/L)
Estimated Site-
Dependent Criteria
Values (µg/L)1
Chronic/Acute Chronic Acute Chronic Acute Chronic Acute
Cohasset
PWA
Lily Pond 87 750 460 1,200 74 120
1. More data points needed to finalize calculations of site dependent criteria values for use in permits. Criteria values do not
equal NPDES permit limits, as additional steps are taken to determine the permit limit.
The Town met with MassDEP on February 24, 2021 to discuss the revised aluminum water quality criteria, review
results of the USGS-MassDEP aluminum study, review the planed implementation of the revised aluminum criteria
in NPDES permits, review treatment plant operations relevant to aluminum, and offer technical assistance. Based
on the meeting discussions, the first individual NPDES/Surface Water Discharge permits may be issued to facilities
in the next 1 to 2 years (possibly later). MassDEP anticipates that these permits will have aluminum limits based on
watershed default criteria due to insufficient data available for site-dependent criteria. The permits will also include
monitoring to support future calculations of site-dependent criteria. The next NPDES/Surface Water Discharge
permit cycle is estimated to occur at least 6 to 7 years from 2021; and would likely have aluminum limits based on
site-dependent criteria.
Considering the historical Lily Pond WTP aluminum data presented in Table 2-7, the Lily Pond WTP is anticipated
to meet future discharge permit limits based on the watershed default criteria for Lily Pond. However, if the
preliminary results from the MassDEP-USGS study are representative of the potential site-dependent criteria value,
mitigation action will likely be required in the future to meet the permit limits based on the site-dependent criteria
value.
Table 2-7. Cohasset Lily Pond WTP Historical Aluminum Data (January 2016 – January 2021)
Total Recoverable Aluminum (µg/L)
Minimum 0
Average 100
Maximum 362
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2.5 CURRENT AND FUTURE COMPLIANCE REVIEW
2.5.1 Current Water Quality and Compliance
A summary of the Town’s compliance summary data from the 2019 Water Quality Report is provided in Tables
2-8 through 2-14. The data demonstrates that the Town is in compliance with drinking water standards. The
treatment processes achieve good microbial inactivation, particulate control, adequate organic removal and DBP
management, and an effective corrosion control strategy.
While the new lead and coper rule was not in effect during sampling, the 2019 sampling results (11 µg/L lead) if
observed in future samplings could impact action needs based on the new LCR as discussed in the following future
considerations section. Additionally, while the Town is in compliance with regulated disinfection byproducts, the
seasonal variability in raw and finished water TOC can cause the potential to produce varying levels of TTHMs and
individual samples approaching or exceeding the TTHM limit. Due to the potential for DBP formation of the organic
laden Lily Pond water supply, the Town conducted a GAC pilot study from August 2020 through January 2021.
Further discussion regarding regulated DBP management and next steps is provided in the following future
considerations section.
Table 2-8. 2019 Microbial Compliance Sampling Results
Microbial
Contaminants
Date
Sampled
MCL MCLG Highest Level
Detected
Range of
Detection
Violation?
(Y/N)
Coliform
Bacteria
Monthly
2019
One positive monthly
sample for systems
that collect less than
40 samples
0 0 0 N
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Table 2-9. 2019 Inorganic Compliance Sampling Results
Inorganic
Contaminants
Date
Sampled
MCL MCLG Highest
Level
Detected
Range of
Detection
Violation?
(Y/N)
Fluoride (ppm) Monthly
2019
4(1) 4 0.9 0.5-0.9 N
Nitrate (ppm) 2019 10 0 2.42 0.16-2.42 N
Barium (ppm) 2019 2 2 0.021 0.018-0.021 N
Chromium
(ppb)
2019 100 6 ND-6 N
Perchlorate
(ppb)
2019 2 N/A 0.21 ND-.21 N
Note: Fluoride also has an optimal level of 0.7 ppm and a secondary MCL of 2 ppm.
Table 2-10. 2019 Disinfectant/Disinfectant Byproducts Compliance Sampling Results
Disinfectant
and
Disinfection
Byproducts
Date
Sampled
Highest
Running
Average
Range
Detected
MCL or
MRDL
MCLG or
MRDLG
Violation?
(Y/N)
Total
Trihalomethanes
(TTHMs) (ppb)
Quarterly,
2019
75 18-120 80 N
Haloacetic Acids
(HAA5) (ppb)
Quarterly,
2019
43 1.7-82 60 N
Chlorine (ppm)
(free)
8 times per
Month
0.42(1) 0.03-1.38 4 4 N
Note: Highest monthly average.
Table 2-11. 2019 Radioactive Contaminants Compliance Sampling Results
Radioactive
Contaminants
Date
Sampled
Highest
Level
Detected
Range
Detected
MCL or
MRDL
MCLG or
MRDLG
Violation?
(Y/N)
Gross Alpha
(pCi/l)
9/12/16 ND 15 0 N
Radium 226 &
228 (pCi/l)
9/12/16 0.76 ND-0.76 5 0 N
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Table 2-12. 2019 Lead and Copper Compliance Sampling Results
Lead &
Copper(1)
Date
Sampled
90th
Percentile
Action
Level
MCLG # sites
above AL
# sites
sampled
Lead (ppb) Jul – Sep
2019
11 15 0 0 24
Copper (ppm) Jul – Sep
2019
0.216 1.3 1.3 0 24
Note:
1. Reduction in frequency for Lead & Copper sampling to every 3 years.
Table 2-13. 2019 Filter Performance Compliance Sampling Results
Turbidity TT Lowest Monthly
% of Samples
Highest Monthly
Value
Violation? (Y/N)
Monthly Maximum
(NTU)
1.0 NTU(1) -- 0.50 No
Monthly Compliance
(NTU)
0.3 NTU(2) 97% -- No
Notes:
• Maximum turbidity limit that the system may not exceed at any time during the month.
• Monthly turbidity compliance is related to a specific treatment technique (TT). The system filters the water so that at
least 95% of our samples each month must be less than or equal to 0.3 NTU.
Table 2-14. 2019 Secondary and ORSG Contaminant Sampling Results
Contaminants Date
Sampled
Highest
Level
Detected
Range of
Detection
Average
Detected
SMCL Health
Advisory
ORSG
Sodium (ppm) 2019 75 37-75 56 -- -- 20
Nickel (ppb) 2019 76 54-76 65 -- -- 100
Cyanotoxins 2018-2019 ND -- -- -- -- --
Manganese
(ppb)
2017 82 ND-82 -- 50 300 --
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2.5.2 Future Water Quality Considerations
2.5.1.1 Disinfection Byproducts
The Town with the assistance of Tetra Tech conducted a GAC pilot study from August 2020 through January 2021
to collect the data necessary to assess the treatment performance and operational requirements of integrating GAC
treatment downstream of the existing filtration process at the Lily Pond WTP. The GAC treatment is intended to
perform as a polishing process to remove additional dissolved organic carbon (DOC) from the treated, filtered water
to reduce formation of DBPs in the distribution system and remove trace organic compounds, such as PFAS. The
purpose of the pilot test is to obtain information to investigate the removal efficiency of the GAC contactors, develop
design criteria for the full scale design and determine the required carbon change out frequency to maintain the
removal of TOC to control the level of disinfection byproduct (DBP) formation.
The GAC pilot system consisted of four (4) columns arranged as two (2) separate and parallel trains—Train A and
Train B. Each of the GAC pilot trains were arranged in two (2) GAC contactor columns in series for a total of four
(4) GAC columns mounted on a pilot skid. The two Trains A and B were operated at two different empty bed contact
times (EBCTs) of 12-15 minutes and 20 minutes, respectively. Over the course of the pilot, the team conducted
weekly water quality sample collection and operational monitoring to gauge treatment performance. The data was
then analyzed to determine the organic removal efficiency for DBP control and develop recommendations relative
to the design of a full-scale system in terms of the DOC removal required, EBCT, bed depth, and carbon change-
out frequency. The recommendations for a full-scale system will be included into the Lily Pond WTP Capital
Improvements Plan (Section 9.0). A summary of the GAC pilot testing methods, results, conclusions, and
recommendations are being compiled into a GAC Pilot Testing Report. The report will be submitted to MassDEP
as part of the WS 21: Approval to Conduct Pilot study and WS 22: Approval of Pilot Study Report requirements.
2.5.2.2 Lead and Copper
The lead result for the 2019 sampling round of 11 µg/L was slightly above the new lead trigger level of greater than
10 µg/L and less than or equal to 15 µg/L for the 90th percentile of samples. If the 90th percentile results fall within
the new lead trigger level range in future sampling rounds, the Town will need to coordinate with MassDEP to
determine whether further action is needed. According to the new rule requirements for small systems (≤10,000
people), the following actions may be needed with 90th Percentile results > 10 µg/L:
• Town can coordinate with MassDEP for selecting approach to address lead, including corrosion control
treatment, lead service line replacement, provision and maintenance of point-of-use devices, or replace all
lead-bearing plumbing materials.
• Sampling frequency may be increased to yearly.
Based on the 2016 EPA Optimal Corrosion Control Treatment Evaluation Technical Recommendations, the
technical recommendation for corrosion control treatment (CCT) is to add orthophosphate. Current corrosion control
treatment at the Lily Pond WTP consists adding a blended phosphate that includes poly and orthophosphate. This
strategy, which includes an orthophosphate component, generally satisfies the EPA treatment recommendations.
Based on this, it is not anticipated that a change in corrosion control treatment would be required.
Relative to the distribution system, the new rule will require that the Town develop a lead service line inventory or
demonstrate absence of lead service lines within the first three (3) years of final rule publication. The new rule may
also require the Town to re-evaluate the lead sampling locations and also conduct additional lead sampling from
elementary schools and childcare facilities.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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2.5.2.3 PFAS
The Town conducted preliminary PFAS sampling from their distribution system entry points prior to the PFAS
regulations taking effect to examine if PFAS would be detected in the water system. Table 2-15 summarizes the
results for the regulated PFAS6 compounds collected from the Lily Pond WTP, Ellms Meadow, and Hingham
interconnect points of entry. The PFAS6 results from the Lily Pond WTP and Hingham point of entries were below
half of the newly adopted 20 ng/L MCL. The PFAS6 levels for the Lily Pond WTP treated water were also found to
remain below half of the MCL during the GAC pilot water quality monitoring for PFAS6. While providing future GAC
treatment at the Lily Pond WTP will help further lower PFAS6 levels, the current PFAS6 levels are below the 10
ng/L MassDEP goal.
On the other hand, the PFAS6 results from the Ellms Meadow point of entry were found to be greater than 10 ng/L
in three of the samples and greater than the 20 ng/L MCL in one of the samples. Although the PFAS6 results from
the Lily Pond WTP and Hingham interconnect demonstrate that finished water blended in the distribution system
could be below 10 ng/L, reducing the PFAS6 levels at Ellms Meadow would allow a consistent supply of higher
quality water throughout the entire service area. In response, the Town applied for and was granted financial
assistance from MassDEP to perform a rapid small scale column test (RSSCT) investigation and prepare design
plans and specifications for additional treatment to reduce the levels of PFAS6 at the Ellms Meadow wellfield prior
to distribution.
Table 2-15. PFAS6 Results
Parameter Lily Pond WTP Point
of Entry
Ellms Meadow
Point of Entry
Whitney Crossing /
Hingham Interconnect
Point of Entry
Sample
Date
6/30/2020 9/2/2020 6/30/2020 9/2/2020 1/08/2021 6/30/2020 9/2/2020
PFHpA 1.6 (J) 1.36 (J) 1.4 (J) 1.68 (J) 2.12 1.5 (J) 1.56 (J)
PFHxS 0.92 (J) 0.733 (J) 3.5 3.79 3.65 1.1(J) 0.728 (J)
PFOA 4.3 3.74 5.6 6.75 7.68 4.4 4.18
PFNA 0.72 (J) 0.733 (J) 1 (J) 0.572 (J) 2.24 0.72 (J) 0.8 (J)
PFOS 3.5 3.7 8.9 8.4 10.1 4 3.06
PFDA ND ND ND ND ND ND ND
PFAS6 7.8 7.44 18.0 18.9 25.8 8.4 7.24
Notes:
1. ND = Not detected.
2. Italics (J) represent qualifier estimated results that are below the method the reporting limit but above the method
detection limit.
3. Sum of PFOS, PFOA, PFHxS, PFNA, PFHpA and PFDA includes results at or above the MRL; and does not include
estimated results as described by a qualifier.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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3.0 CAPACITY ANALYSIS
3.1 OVERVIEW
To set the stage for necessary improvements to the Lily Pond WTP, it is important to first evaluate the existing
capacity of the supply and treatment facilities. Water systems have both general and specific requirements for the
design of water supply, treatment, disinfection, high service pumping, chemical feed, and sludge management
facilities as required by MassDEP, engineering sources, and industry standards. These design criteria, described
in the sections below, form the basis for evaluating the capacity of the water supply and treatment components.
The capacity of the water supply, treatment, disinfection, high service pumping, chemical feed, and sludge
management was evaluated by comparing the existing installed capacity to the capacity required to meet the
demand-based water system average, maximum day, and peak flows.
3.2 EXISTING CONDITIONS
The Town of Cohasset Water Department provides potable water service to 7,523 service area residents and
“wheeled” water to the Linden Ponds senior living community in nearby Hingham through the Hingham/Hull
distribution system from a combination of treated surface water and groundwater sources. The single surface water
source is treated by a conventional coagulation-clarification-filtration treatment process with free chlorine
disinfection at the Lily Pond Water Treatment Plant (WTP). The single groundwater source is supplied from the
Ellms Meadow Wellfield. The wellfield pumps groundwater from a shallow glacial valley aquifer located along James
Brook, which runs through the most heavily developed portion of the Town. To manage both water quality and
demands, the Town targets an approximate 85% to 15% combination from the Lily Pond and Ellms Meadow
sources, respectively. However, in light of recently uncovered PFAS levels above the MassDEP regulatory limits,
the Ellms Meadow Wellfield source has been temporarily placed offline. In response, the Town applied for and was
granted financial assistance from MassDEP to perform a rapid small scale column test (RSSCT) investigation and
prepare design plans and specifications for additional treatment to reduce the levels of PFAS6 at the Ellms Meadow
wellfield prior to distribution.
The Town’s allowable maximum water withdrawal from the individual water sources is regulated by the Final
Renewed Water Management Act Permit (#9P4-4-21-065.01) issued by MassDEP on July 19, 2016. As
summarized in Table 4-1. The maximum authorized daily withdrawal rates for the Ellms Meadow Wellfield and Lily
Pond are 0.17 MGD and 3.0 MGD, respectively. Additionally, the permit sets the current permitted maximum annual
average withdrawal rate to 0.95 MGD over five year increments through 2030 as listed in Table 4-2. The Town will
need to apply for a new permit if annual withdrawals exceed 0.95 MGD.
Based on the original “Cohasset Water Supply Improvements Program” dated 1978 – 1979, the Lily Pond WTP was
designed to treat an average flow of 1.2 MGD and a peak flow of 3.0 MGD. The current average day demand is
approximately 0.8 MGD; and current summer-time maximum day and peak flows are approximately 1.6 MGD and
2.4 MGD, respectively. A summary of these existing conditions is summarized in Table 4-3. To treat and supply the
flows needed to meet these water demands, the Lily Pond WTP relies on the following major water supply,
treatment, and sludge management processes and facilities:
• Lily Pond Raw Water Intake Structure with Bar Screening Pretreatment
• Raw Water Transfer Pumping
• Iron and Manganese Chemical Pretreatment
• Coagulation (Rapid Mix) Basins with Mechanical Mixing
• Flocculation (Slow Mix) Basins with Paddle Mixing
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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• Sedimentation Basins with Tube Settlers
• Dual-Media Rapid Filtration
• Disinfection within Clearwell
• Finished Water/High Service Pumping
• Filter Backwash Pumping
• Process Wastewater Sludge Pumping
• Sludge Lagoons
• Chemical Feed Systems
o Sodium Permanganate for Iron, Manganese and colorremoval
o Pre-Sodium Hydroxide for Pretreatment pH Adjustment
o Ferric Chloride Coagulant
o Polyaluminum Chloride
o Polymer Flocculant Aid
o Solution Feed Gas Chlorination for Primary and Secondary Disinfection
o Post-Sodium Hydroxide for Posttreatment pH Adjustment
o Blended Phosphate Corrosion Control
o Fluoride Addition for Tooth Decay Prevention
Descriptions of these existing water supply, treatment, sludge management, and chemical feed facilities are
presented in Tables 3-4, 3-5, and 3-6.
Table 3-1. Permitted Maximum Authorized Daily Withdrawal Rates
Source PWS Source ID Approved Maximum Daily Rate
(MGD)
Ellms Meadow Wellfield 4065000-02G 0.17
Lily Pond 4065000-02S 3.0
Note:
• Source: Final WMA Permit 9P4-4-21-065.01 (July 19, 2016).
Table 3-2. Permitted Existing Authorized Rate
Permit Period Existing Authorized Rates (MGD)1
2015 - 2020 0.95
2020 - 2025 0.95
2025 - 2030 0.95
Note:
1. Source: Final WMA Permit 9P4-4-21-065.01 (July 19, 2016).
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-3. Current Demands and Installed Facility Capacities
Scenario Current Value Total Installed
Average Day Demand 0.80 MGD 1.2 MGD
Maximum Day Capacity 1.6 MGD 2.4 MGD
Peak Demand 2.4 MGD 3.0 MGD
Note:
• Sources: “Cohasset Water Supply Improvements Program” 1978 – 1979 (Consulting Engineers SEA Consultants Inc.
Engineers/Planners Boston, Ma.) and Historical Water Demands further presented in Section 5.3.)
Table 3-4. Surface Water Supply
Parameter Existing Value or Description
Raw Water Intake
Number of Raw Water Intake Compartments Two (2)
Intake Cross-Section Area, Each 40 ft2
Intake Cross-Section Area, Total 80 ft2
Intake Structure Volume, Firm 5,610 gallons
Intake Structure Volume, Total 8,303 gallons
Screening Quantity and Type Two (2) Coarse Bar-screens
Sluice Gates Quantity and Size Two (2) 36” x 36”
Draining Sump Pumps Two (2) 15 HP Pumps
Raw Water Transfer Pumping
Number of Pumps 2 + 1 Standby
Unit Pump Capacity 1.728 MGD
Firm Pumping Capacity (2 pumps in service) 3.46 MGD
Total Pumping Capacity (3 pumps in service) 5.18 MGD
Note:
• Firm indicates capacity with the largest unit out of service.
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Table 3-5. Treatment Facilities
Unit Operation/Process Existing Value or Description
Pretreatment – Sodium Permanganate
Purpose Iron, Manganese and color removal. Also odor an
taste.
Chemical 20% Sodium Permanganate
Chemical Specific Gravity 1.16
Typical Dose Range 0.5 to 3.5 mg/L
Typical Average Dose 1.5 mg/L
Chemical Feed Pumps 1 + 1 Standby
Chemical Feed Pump Unit Capacity 2.5 gph
Bulk Storage Type Polyethylene Vertical Cylinder
Bulk Storage Volume 300 gallons
Day Tank Type Polyethylene Day Tank, Vertical Cylinder
Day Tank Volume 75 gallons
Storage Time, Average 58 days
Pretreatment – Sodium Hydroxide
Purpose pH Adjustment for Iron and Manganese Oxidation
Chemical 25% Sodium Hydroxide
Chemical Specific Gravity 1.28
Typical Dose Range 5 to 16 mg/L
Typical Average Dose 9.8 mg/L
Chemical Feed Pumps 1 + 1 Standby
Chemical Feed Pump Unit Capacity 10 gph
Day Tank Transfer Pump (for pre & post) One (1) 28 gpm and 27.2 ft maximum head
Bulk Storage Type Polyethylene Vertical Cylinder
Bulk Storage Volume 1,900 gallons (shared with post-sodium hydroxide
feed)
Day Tank Type Polyethylene Day Tank, Vertical Cylinder
Day Tank Volume 200 gallons (dedicated)
Storage Time, Average 44.7 days (including post-sodium hydroxide feed)
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Table 3-5. Treatment Facilities (Cont’d)
Unit Operation/Process Existing Value or Description
Coagulation – Rapid Mix
Number of Rapid Mix Basins 2
Basin Volume, Each 530 gallons
Basin Volume, Total 1,060 gallons
Rapid Mixer Type Mechanical Mixer – Philadelphia Mixing Solutions
Number of Rapid Mixers 2
Rapid Mixer Horsepower 3 HP
Velocity Gradient, G 2,003 1/s
Firm Rapid Mix Detention Time 57 seconds
Total Rapid Mix Detention Time 29 seconds
Flocculation – Slow Mix
Number of Flocculation Basins 2
Basin Volume, Each 20,735 gallons
Basin Volume, Total 41,469 gallons
Rapid Mixer Type Horizontal Flocculator Paddles
Number of Flocculator Paddle Sections 2
Flocculation Mixer Horsepower 1 HP
Firm Flocculation Detention Time 37 minutes
Total Flocculation Mix Detention Time 19 minutes
Sedimentation
Number of Sedimentation Basins 2
Basin Surface Area, Each 492 ft2
Basin Surface Area, Total 984 ft2
Basin Volume, Each 38,642 gallons
Basin Volume, Total 77,283 gallons
Sedimentation Type Rectangular Upflow with Tube Settlers (2 ft height)
Sedimentation Basin Surface Loading Rate, Firm
(gpm/ft2) 2.3 gpm/ft2
Sedimentation Basin Surface Loading Rate, Total
(gpm/ft2) 1.1 gpm/ft2
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-5. Treatment Facilities (Cont’d)
Unit Operation/Process Existing Value or Description
Filtration
Number of Filters 3
Basin Surface Area, Each 169 ft2
Filter Surface Area, Firm 338 ft2
Filter Surface Area, Total 507 ft2
Filter Type Dual Media Anthracite/Sand Rapid Filtration
Filter Loading Rate, Firm 3.3 gpm/ft2
Filter Loading Rate, Total 2.2 gpm/ft2
Number of Backwash Pumps 2
Unit Backwash Pump Capacity, Each 3,400 gpm
Total Backwash Pump Capacity 6,800 gpm
Total Dynamic Head 30 ft
Motor Horsepower 30 HP
Backwash Rate Per Filter with One Pump 20 gpm/ft2
Disinfection
Type Baffled Clearwell
Clearwell Volume 130,000 gallons
Clearwell Baffling Factor 0.73
Inlet and Outlet Pipe Volume 8,477 gallons
Pipe Baffling Factor (assume plug flow) 1.0
Design Free Chlorine Residual 0.6 mg/L
Design Minimum Temperature 5 deg-C
Design pH 7.0
Calculated CT @ Peak Hour Demand 28.5 mg/L-min
310 CMR 22.20A CT Required (Typical) 24 mg/L-min
High Service Pumping
Number of High Service Pumps 2 + 1 Jockey Pump
Unit High Service Pump Capacity, Each 2,100 gpm
High Service Pump Motor Horsepower 150 HP
Jockey Pump Capacity 500 gpm
Jockey Pump Motor Horsepower 40 HP
High Service Pumping Capacity, Firm 2,600 gpm
High Service Pumping Capacity, Total 4,700 gpm
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-5. Treatment Facilities (Cont’d)
Unit Operation/Process Existing Value or Description
Process Wastewater/Backwash Water Pump Station
Number of Wastewater Pumps 2
Unit Wastewater Pump Capacity, Each 3,403 gpm (4.9 MGD)
Wastewater Pump TDH 30 feet
Wastewater Pump Motor Horsepower 30 HP
Wastewater Wetwell Volume 9,166 gallons
Sludge Management – Sludge Removal
Number of Sludge Removal Systems 2
Sludge Removal System Type Chain & Flight
Sludge Removal Mechanisms Mud Valve at Bottom of Sloped Hopper & Pedestal
Valve Above
Sludge Management – Sludge Lagoons
Number of Sludge Lagoons 2
Size of Lagoons, Each 99-ft L x 53-ft W x 6-ft D
Effective Lagoon Area, Each 5,247 ft2
Lagoon Capacity, Each 236,115 gallons
Lagoon Capacity, Total 472,230 gallons
Unit Wastewater Pump Capacity, Each 3,403 gpm (4.9 MGD)
Estimated Sludge Quantity, Average 365 lbs/day
Sludge Collection/Removal Type Sludge Pumping into Water Permeable Geo-Bag
Sludge Disposal Type
Periodic Pick-up and Disposal of Sludge Collected in
Geo-Bag by Third Party Contractor
Note:
1. Firm indicates capacity with the largest unit out of service.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-6. Additional Chemical Feed Systems
Unit Operation/Process Existing Value or Description
Coagulation – Ferric Chloride
Purpose Coagulation
Chemical 40% Ferric Chloride
Chemical Specific Gravity 1.27
Typical Dose Range 1 to 6 mg/L
Typical Average Dose 3.3 mg/L
Chemical Feed Pumps 1 + 1 (high and low range capacity)
Chemical Feed Pump #1 Unit Capacity 1.0 gph
Chemical Feed Pump #2 Unit Capacity 4.0 gph
Storage Type Polyethylene Vertical Cylinder
Storage Volume 80 gallons
Storage Time, Average 15 days
Delivery Ferric Chloride Solution Drums
Coagulation – Polyaluminum Chloride
Purpose Coagulation
Chemical 100% Polyaluminum Chloride
Chemical Specific Gravity 1.27
Typical Dose Range 90 to 220 mg/L
Typical Average Dose 146.2 mg/L
Chemical Feed Pumps 3 (2 + 1 Standby)
Chemical Feed Pump Unit Capacity 14.4 gph
Day Tank Transfer Pump One (1) End-suction pump
Bulk Storage Type Horizontal Fiberglass
Bulk Storage Volume 6,000 gallons
Day Tank Type Polyethylene Day Tank, Vertical Cylinder
Day Tank Volume 200 gallons (dedicated)
Storage Time, Average 65 days
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-6. Additional Chemical Feed Systems (Cont’d)
Unit Operation/Process Existing Value or Description
Flocculation – Polymer
Purpose Flocculation Enhancement
System Type Excell Feeders Model 6014PC-18031
Chemical 100% Polydyne CLARIFLOC® N-6310
Chemical Specific Gravity 1.00
Dilution Factor 0.5% (0.005)
Typical Dose Range 0.2 to 1.5 mg/L
Typical Average Dose 1.0 mg/L
Chemical Feed Pumps 3 (2 + 1 Standby)
Chemical Feed Pump #1 Unit Capacity 10 gph
Chemical Feed Pump #2 & 3 Capacity 8.2 gph
Transfer Pump One (1) Magnetic drive pump
Neat Polymer Storage Tank Capacity 5 gallons
Diluted Polymer Storage Tank Type Polyethylene Tank, Vertical Cylinder
Diluted Polymer Storage Tank Capacity 50 gallons
Disinfection – Pre-Chlorine Upstream of Clearwell
Purpose Primary Disinfection
Chemical 100% Chlorine Gas
Typical Dose Range 1 to 3 mg/L
Typical Average Dose 1.6 mg/L
Chlorine Feed Type Capital Controls Gas Feeder with Solution Feed
Injector
Chlorine Feeder Quantity 1 + 1 Standby (Shared with Post-Cl2)
Chlorine Feeder Capacity 60 – 90 lbs/day
Chlorine Solution Delivery Solenoid Valve with Flow Pacing
Storage Type Chlorine Gas Cylinders
Online Storage Capacity Four (4) 150 lbs (600 lbs)
Max Allowable Spare Cylinders (Total) Four (4) 150 lbs (600 lbs)
Storage Time, Average 56 days (online cylinders)
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-6. Additional Chemical Feed Systems (Cont’d)
Unit Operation/Process Existing Value or Description
Disinfection – Post-Chlorine Downstream of Finished Water Pumps
Purpose Secondary Disinfection
Chemical 100% Chlorine Gas
Typical Dose Range 0.5 to 2.5 mg/L
Typical Average Dose 1.5 mg/L
Chlorine Feed Type Capital Controls Gas Feeder with Solution Feed
Injector
Chlorine Feeder Quantity 1 + 1 Standby (Shared with Pre-Cl2)
Chlorine Feeder Capacity 60 – 90 lbs/day
Chlorine Solution Delivery Two (2) Booster Pumps at 140 psi
Storage Type Chlorine Gas Cylinders
Online Storage Capacity Two (2) 150 lbs (300 lbs)
Max Allowable Spare Cylinders (Total) Four (4) 150 lbs (600 lbs)
Storage Time, Average 30 days (online cylinders)
Post-treatment – Sodium Hydroxide (downstream of finished water pumps)
Purpose pH Adjustment and Stabilization
Chemical 25% Sodium Hydroxide
Chemical Specific Gravity 1.28
Typical Dose Range 6 to 9 mg/L
Typical Average Dose 7.2 mg/L
Chemical Feed Pumps 1 + 1 Standby
Chemical Feed Pump Unit Capacity 6.6 gph
Day Tank Transfer Pump (for pre & post) One (1) 28 gpm and 27.2 ft maximum head
Bulk Storage Type Polyethylene Vertical Cylinder
Bulk Storage Volume 1,900 gallons (shared with post-sodium hydroxide
feed)
Day Tank Type Polyethylene Day Tank, Vertical Cylinder
Day Tank Volume 200 gallons (dedicated)
Storage Time, Average 44.7 days (including post-sodium hydroxide feed)
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Table 3-6. Additional Chemical Feed Systems (Cont’d)
Unit Operation/Process Existing Value or Description
Post-treatment – Blended Phosphate Post Filtration prior to Chlorine
Purpose Corrosion Control
Chemical 34% Blended Phosphate Aquadene TM SK-7641
Chemical Specific Gravity 1.36
Typical Dose Range 0.9 to 3.0 mg/L
Typical Average Dose 2.5 mg/L
Chemical Feed Pumps Two (2)
Chemical Feed Pump #1 Unit Capacity 0.58 gph
Chemical Feed Pump #2 Unit Capacity 0.42 gph
Storage Type Polyethylene Vertical Cylinder
Storage Volume 80 gallons
Storage Time, Average 18.5 days
Post-Treatment – Fluoride Addition Downstream of Finished Water Pumps
Purpose Tooth decay prevention
System Type Fluoride Saturator
Chemical 95% Sodium Fluoride
Saturator Pounds of Active Fluoride per Gallon of
Saturator Make-up Water
0.07 lb/day
Typical Dose Range 0.1 to 0.7 mg/L
Typical Average Dose 0.5 mg/L
Chemical Feed Pumps 1 + 1 Standby
Chemical Feed Pump Unit Capacity 10 gph
Saturator Storage Tank Type Polyethylene Vertical Cylinder
Saturator Storage Tank Capacity 50 gallons
Note:
• Firm indicates capacity with the largest unit out of service.
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3.3 HISTORICAL WATER DEMANDS
A summary of the potable water demands for the Cohasset water system were collected from historical water
production data for the period of 2016 through 2020. Table 3-7 presents the historical total average daily demand
(ADD), maximum day demand (MDD), and minimum month demand (MMD) for the Cohasset water system. A
corresponding time series graph showing these historical water demands is presented in Figure 3-1. As
demonstrated in Figure 3-1, the Cohasset water system exhibits seasonal variation in water demands. Maximum
day and peak demands occur during the high-demand summer months; and lower demands occur during the winter
months. To manage both water quality and demands (particularly during the summer), the Town typically targets
an approximate 85% to 15% combination from the Lily Pond and Ellms Meadow sources, respectively. The
maximum to average demand (MDD:ADD) and minimum month demand (MMD:ADD) factors for the system are
also included in Table 3-7.
As shown in Table 3-7, the highest average water demand for the Cohasset water system occurred in 2020.
Increases in water demand during 2020 can be attributed to the COVID-19 pandemic as stay at home orders and
a shift to working from home have increased home water usage. Prior to the ongoing pandemic however, the potable
water demand from the Cohasset water system has historically remained relatively constant, averaging around 0.78
MGD. These relatively constant historical water demands are due to a steady, slowly growing service area
population and conservation efforts to reduce water consumption in the area. Including the 2020 flows, the average
day demand over the past five years is approximately 0.8 MGD.
The historical MDD:ADD ratio for the Cohasset water system has ranged from 1.9 to 2.3 with an average factor of
about 2.0. The minimum month to average demand (MMD:ADD) ratio was observed as 0.6 to 0.7, on average. The
current maximum hourly rate from the Lily Pond WTP is approximately 2.4 MGD, which corresponds to a current
peak hour factor of 3.0 times the average day demand. The design peak hour factor based on the original basis of
design for the facility is 2.5. A summary of the system demand factors is Table 3-8.
Table 3-7. Cohasset Water System Historical Demand Summary
Demand 2016 2017 2018 2019 2020 Average
(2016 –
2019)
Average
(2016 –
2020)
Average Day
Demand (ADD) 778,328 756,182 809,592 785,783 895,272 782,471 805,031
Maximum Day
Demand (MDD) 1,700,817 1,461,400 1,601,125 1,525,466 2,072,941 1,572,202 1,672,350
Minimum Month
Demand (MMD) 514,442 474,278 517,194 534,680 397,132 510,148 487,545
MDD:ADD Factor 2.2 1.9 2.0 1.9 2.3 2.0 2.1
MMD:ADD Factor 0.7 0.6 0.6 0.7 0.4 0.7 0.6
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
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Figure 3-1. Cohasset Water System Historical Flows
Table 3-8. Assumed Peaking Factors for Water System Planning
Peaking Factor Planning Value
Minimum Month 0.7
Maximum Day 2.0
Current Peak Hour 3.0
Design Peak Hour 2.51
Note:
• Design peak hour flow factor based on original basis of design of facility of 3.0 MGD maximum rate and 1.2 MGD
average rate.
3.4 FUTURE WATER PROJECTIONS
With the renewal of the Water Management Act Permit (No. 9P4-4-21-064.01), the MassDEP regulated Cohasset’s
water production to limit nonessential water use, thus lowering the residential gallons per capita day (RGPCD)
standard from 80 gallons per capita-day to 65 gallons or less. Additionally, the performance standard for
unaccounted-for-water (UAW) was reduced from 15% to 10%. Compliance with the RGPCD and UAW requirements
were required by December 31, 2018 and December 31, 2019, respectively.
0
500,000
1,000,000
1,500,000
2,000,000
2,500,000
3,000,000
Jul-15 Jan-16 Aug-16 Mar-17 Sep-17 Apr-18 Oct-18 May-19 Dec-19 Jun-20 Jan-21 Jul-21Flow (GPD)Date
ADD MDD Peak Hour
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The MassDEP Department of Conservation and Recreation, Office of Water Resources (DCR) developed future
water needs forecasts for Cohasset based on the regulated 65 RGPCD and assuming a 10 percent unaccounted-
for water, which is representative of possible leaks in the distribution system. The water predictions developed by
the DRC are summarized in Table 3-9. A combined summary of historical and forecasted water needs are presented
in Figure 3-2. The corresponding permitted maximum and average rates are also shown in Figure 3-2. Overall, the
3.0 MGD maximum permitted withdrawal rate is sufficient to meet peak flows throughout the 2030 forecast. Based
on the water need projections, the Town may need to consider applying for an increase in the authorized annual
average withdrawal rate of 0.95 MGD for projected high demands around 2022. Since current average demands
are approximately 0.8 MGD, it is recommended that the Town continue to monitor average daily demands to
determine if or when a modification of the authorized annual average withdrawal rate may be necessary.
The water forecast was developed for the needs of the Cohasset population and for the Linden Ponds retirement
community in Hingham, MA with which Cohasset is under contract to supply up to 0.306 MGD of water via an
interconnect with the Aquarion Water Company. Additionally, there were considerations in the demand projections
to include a portion of the Aquarion/Hingham distribution system located in North Cohasset. Consequently, these
potential customers that would exert an additional water demand of approximately 0.065 MGD were added to the
projections for the Cohasset water system.
Water use predictions from 2021 to 2025 for existing customers (the Cohasset system and the Linden Ponds
retirement community) is 0.98 MGD. If including the potential takeover of North Cohasset, the total water demand
is approximately 1.041 MGD. The predicted water demand reduces from 1.041 to 1.031 MGD for the 2026 to 2030
period, representing an assumed 1 percent decrease in estimated water needs. For the following 2026 to 2013
period, the demands are projected as 1.064 MGD and include a 5 percent safety factor to account for increases in
the Town’s service area population.
Table 3-9. DCR Water Needs Forecast for Cohasset
Description1,2 2021-2025
(MGD)
2026-2030
(MGD)
2026-2030 + 5% Buffer for
Town (MGD)
Flow Scenario ADD MDD3 Peak
Hour4
ADD MDD3 Peak
Hour4
ADD MDD3 Peak
Hour4
DCR Projection
for Cohasset
System
0.670 1.34 2.01 0.660 1.32 1.98 0.693 1.386 2.079
Sales to Linden
Ponds via
Aquarion
0.306 0.306 0.306 0.306 0.306 0.306 0.306 0.306 0.306
Potential
Takeover of
North Cohasset
0.065 0.13 0.195 0.065 0.13 0.195 0.065 0.13 0.195
Total Forecast 1.041 1.776 2.32 1.031 1.756 2.51 1.064 1.822 2.58
Notes:
1. Demand projections/forecast retrieved from the Town’s Water Management Act Permit (No. 9P4-4-21-064.01).
2. Demand projections/forecast assume a 65 RGPCD and 10% unaccounted-for water.
3. MDD based on 2.0 peaking factor.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
48 200-121837-20003
4. Peak hour based on 3.0 peaking factor.
Figure 3-2. Historical and Forecasted Water Needs
3.5 CAPACITY AND PROCESS REVIEW
A capacity and process evaluation was performed to determine the effective capacities of the existing major unit
processes, facilities, and chemical feed systems. The effective capacities were determined using standard
engineering design values, equipment data, design data, basin dimensions, and information gathered through
discussions with the WTP operations and maintenance team. The analysis considered both total and firm (largest
unit out of service) capacities. The total and firm effective capacities were analyzed to assess the ability of the unit
processes to meet current demands and the rated capacity of the WTP based on the following scale:
a. Adequate: Actual capacity is 100% or greater than the rated capacity.
b. Marginal: Actual capacity is 90% to <100% of the rated capacity.
c. Not Adequate: Actual capacity is <90% of the rated capacity.
The capacity and process evaluation encompassed the following processes and unit operations:
1. Intake Structure
2. Raw Water Pumps
3. Rapid Mix Basins
4. Flocculation Tanks
0
0.5
1
1.5
2
2.5
3
3.5
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Authorized Rate, Average (MGD)
Lily Pond Summer Maximum Hourly Rate (MGD)Maximum Day Demand (MGD)
Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Authorized Average Rate
Peak Hour
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
49 200-121837-20003
5. Sedimentation Basins
6. Filters
7. Filter Backwash Pumps
8. Process Wastewater Pumps
9. Clearwell (mixing and CT)
10. Finished Water Pumps
11. Sludge Holding
12. Sodium Permanganate Feed System
13. Sodium Hydroxide Feed System
14. Ferric Chloride Feed System
15. Polyaluminum Chloride Feed System
16. Polymer Feed System
17. Chlorine Feed System
18. Blended Phosphate Feed System
19. Fluoride Feed System
The results of the capacity and process evaluation for the major supply, treatment, sludge management, and
chemical feed systems are provided in Tables 3-10 and 3-11. Graphical representations of the effective capacities
as compared to the current and projected demands are included in Figures 3-3 through 3-9. A summary of the
findings is provided as follows:
1. Raw Water Supply
a. Raw water intake structure and raw water transfer pumps have adequate firm and total capacity to meet
current and 3.0 MGD rated maximum capacity.
2. Iron and Manganese Pretreatment
a. In warmer summer months, the existing mixing contact time is sufficient to adequately meet average
and maximum day demands; and marginally meet current 2.4 MGD peak flows. The existing contact
time is not sufficient to meet the 3.0 MGD rated maximum capacity.
b. In cold winter months, the existing mixing contact time is sufficient to adequately meet average and
maximum day demands; but is not sufficient to meet 2.4 MGD or 3.0 MGD peak maximum flows.
c. It is recommended that the point of permanganate injection be re-located upstream within the raw water
intake structure to allow a longer mixing contact time.
3. Coagulation (Rapid Mix)
a. The coagulation basins and mixer horsepower have adequate firm and total capacity to meet current
and 3.0 MGD rated maximum capacity.
4. Flocculation (Slow Mix)
a. Evaluation at 30-minute Optimum Detention Time
i. The firm flocculation basin capacity is limited to only meeting current average day flows.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
50 200-121837-20003
ii. The total flocculation basin capacity is adequate to meet current average and maximum day flows;
is marginally adequate to meet 2.4 MGD peak flows; and not adequate to meet the 3.0 MGD rated
maximum flow.
b. Evaluation at 20-minute Detention Time (Potential Diminishing of Performance)
i. The firm flocculation basin capacity is limited to meeting current average day flows and marginally
meeting current maximum day flows.
ii. The total flocculation basin capacity is adequate to meet current and 3.0 MGD rated maximum
capacity, but could experience a diminishing in treatment performance.
c. MassDEP guidelines require two (2) basins, but do not require meeting capacities with one basin offline.
5. Sedimentation
a. The firm sedimentation basin capacity is limited to only meeting current average day flows.
b. The total sedimentation basin capacity is adequate to meet current average, maximum, and peak flows;
and is marginally adequate to meet the 3.0 MGD rated maximum flow.
c. MassDEP guidelines require two (2) basins, but do not require meeting capacities with one basin offline.
6. Filtration
a. The firm filtration capacity (with one filter out of service) is adequate to meet current average, maximum,
and peak flows; and is not adequate to meet the 3.0 MGD rated maximum flow.
b. The total filtration capacity is adequate to meet current and 3.0 MGD rated maximum capacity.
c. The filter backwash pumping with one pump out of service has adequate capacity to backwash one (1)
filter at a time.
d. Surface water treatment rule requires that the rated capacity be met with one filter out of service.
7. Disinfection Clearwell
a. Disinfection clearwell has adequate effective contact time (CT) capacity to meet current and 3.0 MGD
rated maximum capacity.
8. High Service Pumping
a. The firm and total capacity of the finished water pumps is adequate to meet current and 3.0 MGD rated
maximum capacity.
9. Process Wastewater Pumps
a. The existing process wastewater pumps have adequate capacity to pump to waste the filter backwash
flow rate.
10. Sludge Management
a. The existing sludge lagoons can support an average flow of 0.64 MGD based on a solids loading of 8.2
lb/ft2 (for a wet region). At this effective capacity, the sludge lagoons appear to be not adequate for
current and 3.0 MGD rated maximum capacity.
11. Chemical Feed Systems
a. Overall, existing chemical storage and feed systems have adequate capacities to meet current and 3.0
MGD rated maximum capacity.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
51 200-121837-20003
b. The sodium hydroxide bulk storage capacity is marginally adequate to meet the 3.0 MGD rated
maximum capacity.
c. The ferric chloride storage capacity is marginally adequate to meet the 3.0 MGD rated maximum
capacity.
d. The polymer feed pumps with one pump out of service are capable of delivering a 1.5 mg/L maximum
dose at current average flows and marginally at maximum day flows. The feed pumps with one pump
out of service are not adequate for delivering a 1.5 mg/L maximum dose at 2.4 MGD peak and 3.0
MGD maximum rate flows. At the typical dose of 1.0 mg/L, the polymer feed pumps with one pump out
of service are capable of marginally meeting a 2.4 MGD peak flow and are not capable of meeting the
3.0 MGD maximum rate. If needed, increasing the strength of the polymer feed could be investigated.
e. With the largest feed pump out of service, the blended phosphate feed system can adequately deliver
the maximum phosphate dose at current average and maximum day flows; but cannot adequately meet
2.4 MGD and 3.0 MGD. The total feed pump capacity can adequately meet the 3.0 MGD maximum
rate. The existing storage capacity is not adequate for providing at least 15 days of storage at the 3.0
MGD maximum rate capacity.
f. The firm feed capacity of the fluoride pumps can marginally the maximum dose at the 3.0 MGD
maximum rate.
The Lily Pond WTP was originally designed for a total rated capacity of 3.0 MGD. However, our capacity evaluation
reveals that the total rated capacity is limited to 2.8 MGD by the existing effective capacity of the sedimentation
basins. This total 2.8 MGD rated capacity is based on not exceeding a maximum 2.0 gpm/ft2 across both
sedimentation basins. The firm capacity of the facility with one (1) filter basin out of service was found to be 2.43
MGD at a maximum 5.0 gpm/ft2 loading rate. Although the existing flocculation basins have sufficient volume to
provide 20 minutes of detention time at a total 3.0 MGD flow, some diminishing of the overall plant flocculation and
organic removal performance can be experienced for flows greater than 2.0 MGD. Additionally, the sludge lagoons
are currently operating near their theoretical maximum capacities.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
52 200-121837-20003
Table 3-10. Capacity and Process Evaluation Results – Supply, Treatment & Sludge Management
Process Quantity Basis of Design Industry
Standard or
MassDEP Value
Firm vs Total Effective
Capacity
Acutal Value @
2.4 MGD
Actual Value @
3.0 MGD
Ability to Meet
0.8 MGD Avg
Day Demand
Ability to Meet
1.6 MGD Max
Day Demand
Ability to Meet
2.4 MGD Peak
Demand
Ability to Meet
3.0 MGD Rated
Max Capacity
Raw Water Supply and Pretreatment
Raw Water
Intake Structure 2 Sections Intake Velocity 0.5 fps
Firm 12.9 MGD 0.09 fps 0.12 fps Adequate Adequate Adequate Adequate
Total 25.9 MGD 0.05 fps 0.06 fps Adequate Adequate Adequate Adequate
Raw Water
Transfer Pumps 3 Pumps Meet Maximum
Rated Capacity 3.0 MGD
Firm 3.45 MGD 3.45 MGD 3.45 MGD Adequate Adequate Adequate Adequate
Total 5.18 MGD 5.18 MGD 5.18 MGD Adequate Adequate Adequate Adequate
Fe & Mn
Pretreatment 1 Wetwell
Contact Time -
Summer 5 min @ 20 oC
Firm -- -- -- -- -- --
Total 2.2 MGD 4.6 min 3.7 min Adequate Adequate Marginal Not Adequate
Contact Time -
Winter 10 min@ 1 oC
Firm -- -- -- -- -- -- --
Total 1.1 MGD 4.6 min 3.7 min Adequate
(Winter Average)
Adequate
(Winter Max) Not Adequate Not Adequate
Coagulation & Flocculation Treatment
Coagulation –
Rapid Mix
2 Basins &
Mechanical
Mixers
Detention Time 15 - 30 seconds
Firm 3.05 MGD (at 15
sec) 19 15 Adequate Adequate Adequate Adequate
Total 3.05 MGD (at 30
sec) 38 31 Adequate Adequate Adequate Adequate
Flocculation –
Slow Mix
2 Basins &
Paddle Mixers
Detention Time
(optimum/ideal) 30 minutes
Firm 1.0 MGD 12 10 Adequate Not Adequate Not Adequate Not Adequate
Total 2.0 MGD 25 20 Adequate Adequate Marginal/Not
Adequate Not Adequate
Detention Time
(marginal-
potential
diminished
performance)
20 minutes
Firm 1.5 MGD 12 10 Adequate Marginal Not Adequate Not Adequate
Total 3.0 MGD 25 20 Adequate Adequate Adequate Adequate
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
53 200-121837-20003
Table 3-10. Capacity and Process Evaluation Results – Supply, Treatment & Sludge Management (Cont’d)
Process Quantity Basis of Design Industry
Standard or
MassDEP Value
Firm vs Total Effective
Capacity
Actual Value @
2.4 MGD
Actual Value @
3.0 MGD
Ability to Meet
0.8 MGD Avg
Day Demand
Ability to Meet
1.6 MGD Max
Day Demand
Ability to Meet
2.4 MGD Peak
Demand
Ability to Meet
3.0 MGD Rated
Max Capacity
Sedimentation Treatment
Sedimentation 2 Basins
Surface Loading
Rate – Total Area 2.0 gpm/ft2
Firm 1.4 MGD 3.4 gpm/ft2 4.2 gpm/ft2 Adequate Not Adequate Not Adequate Not Adequate
Total 2.8 MGD 1.7 gpm/ft2 2.1 gpm/ft2 Adequate Adequate Adequate Marginal
Surface Loading
Rate – Tube
Settlers
2.7 gpm/ft2
Firm 1.4 MGD 4.6 gpm/ft2 5.8 gpm/ft2 Adequate Not Adequate Not Adequate Not Adequate
Total 2.8 MGD 2.3 gpm/ft2 2.9 gpm/ft2 Adequate Adequate Adequate Marginal
Filtration Treatment
Filtration 3 Filters Surface Loading
Rate 5.0 gpm/ft2
Firm 2.43 MGD 4.9 gpm/ft2 6.2 gpm/ft2 Adequate Adequate Adequate Not Adequate
Total 3.65 MGD 3.3 gpm/ft2 4.1 gpm/ft2 Adequate Adequate Adequate Adequate
Filter Backwash
Pumps 2 Pumps Backwash Rate 15 gpm/ft2
Firm 3,400 gpm 20 gpm/ft2
(1 filter)
20 gpm/ft2
(1 filter) Adequate Adequate Adequate Adequate
Total 6,800 gpm 20 gpm/ft2
(2 filters)
20 gpm/ft2
(2 filters) Adequate Adequate Adequate Adequate
Disinfection
Disinfection
Clearwell 1 Clearwell
0.5-log Giardia
CT @ 0.6 mg/L
Cl2
24 mg/L-min
Firm -- -- -- -- -- -- --
Total 3.8 MGD 38 mg/L-min 30 mg/L-min Adequate Adequate Adequate Adequate
High Service Pumping
Finished Water
Pumps
2 Pumps + 1
Jockey Pump
Meet Maximum
Rated Capacity 3.0 MGD
Firm 3.7 MGD1 3.7 MGD 3.7 MGD Adequate Adequate Adequate Adequate
Total 6.8 MGD1 6.8 MGD 6.8 MGD Adequate Adequate Adequate Adequate
Sludge Management
Process
Wastewater
Pumps
2 Pumps Filter Backwash
Capacity 3,400 gpm
Firm 3,400 gpm 3,400 gpm 3,400 gpm Adequate Adequate Adequate Adequate
Total 6,700 gpm 6,700 gpm 6,700 gpm Adequate Adequate Adequate Adequate
Sludge Lagoons 2 Lagoons
Sludge Loading
Rage – Wet
Region
8.2 lb/ft2
Firm 0.32 MGD 20.6 lb/ft2 38.6 lb/ft2 Not Adequate Not Adequate Not Adequate Not Adequate
Total 0.64 MGD 10.3 lb/ft2 19.3 lb/ft2 Not Adequate Not Adequate Not Adequate Not Adequate
Notes:
• Firm finished water pump capacity includes jockey pump at an estimated capacity of 500 gpm based on 40 HP motor.
• Solids loading is based on average flows; therefore, total sludge lagoon area meets current average water production.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
54 200-121837-20003
Table 3-11. Capacity and Process Evaluation Results – Chemical Feed Systems
Process Quantity Basis of Design Industry
Standard or
MassDEP Value
Firm vs Total Existing Value Required @ 2.4
MGD
Required @ 3.0
MGD
Ability to Meet
0.8 MGD Avg
Day Demand
Ability to Meet
1.6 MGD Max
Day Demand
Ability to Meet
2.4 MGD Peak
Demand
Ability to Meet
3.0 MGD Rated
Max Capacity
Pretreatment
Sodium
Permanganate
2 Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
1.88 gph @ 3.5
mg/L & 3.0 MGD
Firm 2.5 gph 1.51 gph 1.88 gph Adequate Adequate Adequate Adequate
Total 5.0 gph 1.51 gph 1.88 gph Adequate Adequate Adequate Adequate
1 Day Tank
Storage Time &
Volume @
Average Rated
Capacity
1 day; 10 gal Total 15 days; 75 gal 15 days; 75 gal 7.5 days; 75 gal Adequate Adequate Adequate Adequate
1 Bulk Tank
Storage Time @
Average Rated
Capacity
30 days; 300 gal Total 60 days; 300 gal 60 days; 300 gal 30 days; 300 gal Adequate Adequate Adequate Adequate
Pre & Post pH Adjustment
Sodium
Hydroxide - Pre
2 Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
6.3 gph @ 16
mg/L & 3.0 MGD
Firm 10 gph 5.0 gph 6.3 gph Adequate Adequate Adequate Adequate
Total 20 gph 5.0 gph 6.3 gph Adequate Adequate Adequate Adequate
1 Day Tank
Storage Time &
Volume @
Average Rated
Capacity
1 day; 50 gal Total 8.2 days; 200 gal 8.2 days; 200 gal 4.4 days; 200 gal Adequate Adequate Adequate Adequate
Sodium
Hydroxide - Post
2 Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
3.5 gph @ 9
mg/L & 3.0 MGD
Firm 6.6 gph 2.8 gph 3.5 gph Adequate Adequate Adequate Adequate
Total 13.2 gph 2.8 gph 3.5 gph Adequate Adequate Adequate Adequate
1 Day Tank
Storage Time &
Volume @
Average Rated
Capacity
1 day; 35 gal Total 11 days; 200 gal 11 days; 200 gal 5.9 days; 200 gal Adequate Adequate Adequate Adequate
Sodium
Hydroxide Bulk
Storage (Pre &
Post)
1 Bulk Tank
Storage Time @
Average Rated
Capacity
30 days; 2,400
gal Total 44.7 days; 1,900
gal
44.7 days; 1,900
gal
23.9 days; 1,900
gal Adequate Adequate Adequate Marginal
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
55 200-121837-20003
Table 3-11. Capacity and Process Evaluation Results – Chemical Feed Systems (Cont’d)
Process Quantity Basis of Design Industry
Standard or
MassDEP Value
Firm vs Total Existing Value Required @ 2.4
MGD
Required @ 3.0
MGD
Ability to Meet
0.8 MGD Avg
Day Demand
Ability to Meet
1.6 MGD Max
Day Demand
Ability to Meet
2.4 MGD Peak
Demand
Ability to Meet
3.0 MGD Rated
Max Capacity
Coagulation
Ferric Chloride
2 Pumps (high &
low range)
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
1.5 gph @ 6
mg/L & 3.0 MGD
Firm 1.0 gph / 4.0 gph 1.2 gph 1.5 gph Adequate Adequate Adequate Adequate
Total 5.0 gph 1.2 gph 1.5 gph Adequate Adequate Adequate Adequate
1 Storage Tank &
2 Drums
Storage Time @
Average Rated
Capacity
15 to 30 days; Total
15 days; 80 gal
(28 days with 2
drums; 140 gal)
15 days; 80 gal
(28 days with
drums; 140 gal)
8 days; 80 gal
(14 days with 2
drums; 140 gal)
Adequate Adequate Adequate Marginal
Polyaluminum
Chloride
3 Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
21.6 gph @ 220
mg/L & 3.0 MGD
Firm 28.8 gph 17.3 gph 21.6 gph Adequate Adequate Adequate Adequate
Total 43.2 gph 17.3 gph 21.6 gph Adequate Adequate Adequate Adequate
1 Day Tank
Storage Time &
Volume @
Average Rated
Capacity
1 day; 175 gal Total 2.2 days; 200 gal 2.2 days; 200 gal 1.2 days; 200 gal Adequate Adequate Adequate Adequate
1 Bulk Tank
Storage Time @
Average Rated
Capacity
30 days; 5,200
gal Total 65 days; 6,000
gal
65 days; 6,000
gal
34.7 days; 6,000
gal Adequate Adequate Adequate Adequate
Flocculation
Polymer 3 Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
37.5 gph @ 1.5
mg/L & 3.0 MGD
Firm 18.2 gph 30 gph 37.5 gph Adequate Marginal
Not Adequate Not Adequate
Total 26.4 gph 30 gph 37.5 gph Adequate Adequate Marginal Not Adequate
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
37.5 gph @ 1.0
mg/L & 3.0 MGD
Firm 18.2 gph 20 gph 25 gph Adequate Adequate Marginal Not Adequate
Total 26.4 gph 30 gph 37.5 gph Adequate Adequate Adequate Adequate
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
56 200-121837-20003
Table 3-11. Capacity and Process Evaluation Results – Chemical Feed Systems (Cont’d)
Process Quantity Basis of Design Industry
Standard or
MassDEP Value
Firm vs Total Existing Value Required @ 2.4
MGD
Required @ 3.0
MGD
Ability to Meet
0.8 MGD Avg
Day Demand
Ability to Meet
1.6 MGD Max
Day Demand
Ability to Meet
2.4 MGD Peak
Demand
Ability to Meet
3.0 MGD Rated
Max Capacity
Disinfection
Primary
Chlorination
2 Gas Feeders
with Solution
Feed Injectors
(Standby shared
with post/
secondary)
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
75 lb/day @ 3.0
mg/L & 3.0 MGD
Firm 60 – 90 lb/day 60 lb/day 75 lb/day Adequate Adequate Adequate Adequate
Total 120 – 180 lb/day 60 lb/day 75 lb/day Adequate Adequate Adequate Adequate
4-150 lb Gas
cylinders
Storage Time @
Average Rated
Capacity
15 days; 300 lbs Total 56 days; 600 lbs 56 days; 600 lbs 30 days; 600 lbs Adequate Adequate Adequate Adequate
Secondary
Chlorination
2 Gas Feeders
with Solution
Feed Injectors
(Standby shared
with pre/primary)
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
63 lb/day @ 2.5
mg/L & 3.0 MGD
Firm 60 – 90 lb/day 50 lb/day 63 lb/day Adequate Adequate Adequate Adequate
Total 120 – 180 lb/day 50 lb/day 63 lb/day Adequate Adequate Adequate Adequate
2-150 lb Gas
cylinders
Storage Time @
Average Rated
Capacity
15 days; 280 lbs Total 30 days; 300 lbs 30 days; 300 lbs 16 days; 300 lbs Adequate Adequate Adequate Adequate
Post-Treatment
Blended
Phosphate
2 Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
0.81 gph @ 3
mg/L & 3.0 MGD
Firm 0.42 gph 0.68 gph 0.81 gph Adequate Adequate Not Adequate Not Adequate
Total 1.0 gph 0.68 gph 0.81 gph Adequate Adequate Adequate Adequate
1 Storage Tank
Storage Time @
Average Rated
Capacity
15 days; 125 gal Total 18.5 days; 80 gal 18.5 days; 80 gal 10 days; 80 gal Adequate Adequate Adequate Not Adequate
Fluoride
Saturator 2 Feed Pumps
Supply Maximum
Dose Rate @
Maximum Rated
Capacity
10.62 gph @ 0.7
mg/L & 3.0 MGD
Firm 10 gph 8.5 gph 10.62 gph Adequate Adequate Adequate Marginal
Total 20 gph 8.5 gph 10.62 gph Adequate Adequate Adequate Adequate
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
57 200-121837-20003
Figure 3-3. Lily Pond WTP Raw Water Supply Pumping Capacity vs Demand
Figure 3-4. Manganese Pretreatment Contact Capacity vs Demand
0
1
2
3
4
5
6
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Total Capacity
Existing Firm Capacity Lily Pond Summer Maximum Hourly Rate (MGD)
Maximum Day Demand (MGD)Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Firm Raw Water Capacity
Total Raw Water Capacity
Peak Hour
0
0.5
1
1.5
2
2.5
3
3.5
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Summer Capacity
Existing Winter Capacity Lily Pond Summer Maximum Hourly Rate (MGD)
Maximum Day Demand (MGD)Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Winter Capacity
Peak Hour
Summer Capacity
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
58 200-121837-20003
Figure 3-5. Flocculation Capacity vs Demand
Figure 3-6. Sedimentation Capacity vs Demand
0
0.5
1
1.5
2
2.5
3
3.5
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Total Capacity
Existing Firm Capacity Lily Pond Summer Maximum Hourly Rate (MGD)
Maximum Day Demand (MGD)Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Existing Firm
Existing Total
Peak Hour
0
0.5
1
1.5
2
2.5
3
3.5
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Total Capacity
Existing Firm Capacity Lily Pond Summer Maximum Hourly Rate (MGD)
Maximum Day Demand (MGD)Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Existing Firm
Existing Total
Peak Hour
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
59 200-121837-20003
Figure 3-7. Filtration Capacity vs Demand
Figure 3-8. Disinfection Clearwell Capacity vs Demand
0
0.5
1
1.5
2
2.5
3
3.5
4
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Total Capacity
Existing Firm Capacity Lily Pond Summer Maximum Hourly Rate (MGD)
Maximum Day Demand (MGD)Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Existing Firm
Existing Total
Peak Hour
0
0.5
1
1.5
2
2.5
3
3.5
4
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Total Capacity
Lily Pond Summer Maximum Hourly Rate (MGD)Maximum Day Demand (MGD)
Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Clearwell Capacity @ 24 CT
Peak Hour
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
60 200-121837-20003
Figure 3-9. Finished Water/High Service Pumping Capacity vs Demand
0
1
2
3
4
5
6
7
8
2014 2016 2018 2020 2022 2024 2026 2028 2030 2032Water Flow (MGD)Year
Lily Pond Approved Maximum Daily Rate (MGD)Existing Total Capacity
Existing Firm Capacity Lily Pond Summer Maximum Hourly Rate (MGD)
Maximum Day Demand (MGD)Average Day Demand (MGD)
MDD
ADD
Approved Max Day Withdrawal
Existing Firm
Existing Total
Peak Hour
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
61 200-121837-20003
4.0 PROJECT PRIORITIZATION METHODOLOGY
4.1 OVERVIEW
The existing assets at the Lily Pond WTP were evaluated based on the current condition in order to determine the
need for necessary improvements. The condition coupled with average service lifes defines in general when the
necessary improvements should occur. Mechanical process equipment was further evaluated using a business
risk evaluation (BRE) that uses criticality in addition to condition to prioritize improvements
The BRE looks at an asset’s condition and its criticality to establish the priority for actions on the Mechanical Process
assets. Assets whose condition is poor and whose failure would have a lager impact on the facility overall will
receive priority action. While assets that have a lower criticality and better condition will receive a lower priority. The
BRE process used follows the five steps shown in Figure 4-1 below.
Figure 4-1. Business Risk Evaluation
• Step1: Determine and identify the condition and criticality factors that are used to evaluate the system.
• Step 2: Collect the data that is used to evaluate the condition and criticality factors.
• Step 3: Assign levels to each condition and criticality factor. The purpose of assigning levels is to
differentiate assets based on their condition and criticality.
• Step 4: Calculate a condition and criticality rating for each asset. These ratings are calculated by using the
level assigned to each factor and the relative importance of each factor.
• Step 5: Use the ratings to prioritize the system and determine short-term and long-term action.
The factors and scales for both condition and criticality were developed through discussions and a workshop with
Town of Cohasset personnel and the Lily Pond WTP operations staff. A copy of the minutes and results of the
Prioritization Workshop is provided in Appendix B.
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4.2 CONDITION SCALE AND FACTORS
The condition of the assets was determined through a number of means including on-site visual inspections, review
of available data and reports, and interviews with on-site operating personnel. A detailed description of the on-site
review is presented in Section 5.0. The condition scale that was developed is shown in Table 4-1.
Table 4-1. Condition Scale
Score Condition Expected Remaining
Service Life
Expected Remaining
Service Life
(Prioritization)
1 New, very good condition 100% – 90% 95%
2 Good condition, no improvements
recommended to maintain function.
90% - 60% 75%
3 Fair condition, some improvements may
be required to maintain function
40% - 60% 50%
4 Poor condition, some improvements may
be required to maintain function
40% - 20% 30%
5 Imminent failure, rehabilitation or
replacement required to maintain
function
20% - 0% 10%
The condition scale was used to represent the condition of the asset of all disciplines included in the review. For all
disciplines except mechanical process assets the condition score is used to prioritize renewal and replacement
activities based on the estimated remaining service life. A schedule of the service lives used in the analysis is shown
in Table 4-2 below.
Projects determined by condition assessment are prioritized based on remaining service life using the following
formula:
Asset Remaining Useful Life (yrs) = Average Service Life (yrs) x Remaining Service Life (%)
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Table 4-2. Average Service Life of Assets
Discipline Asset Type Design Life (Years)
Process Mechanical General
Water Pumps
Piping
Gates
Rapid Mix/Flocculation/Sedimentation t
Filter Underdrains and Troughs
Chemical Storage Tanks and Pumps
25
30
50
20
30
30
20
Electrical General
Distribution Panels
MCCs
Grounding
Transformers
VFDs
Generator and Automatic Transfer Switch
Control Panels
Disconnects
25
20
25
25
20
20
20
20
20
SCADA/Instrumentation General
SCADA
Servers
Actuators
PLCs
Level/Pressure Sensors
Meters
15
10
5
15
15
20
20
Structural General
Concrete
Steel
Miscellaneous Metals
30
50
50
25
Architectural/Workplace Safety General
Windows and Doors
Door Hardware
Roofing and Roof Drainage System
Louvers
Floors
50
40
40
20
25
50
HVAC Air Handling Units
Self-Contained AC Units
Hydronic Unit and Cabinet Hydronic Heaters
Electric Unit Heaters
Water Heater
Exhaust Fans
Ductwork
Plumbing Fixtures
General Piping (Hydronic, Refrigerant, etc.)
20
15
20
15
15
20
30
15
20
Site Civil/Security General 50
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4.3 CRITICALITY SCALE AND FACTORS
The criticality criteria define the expected consequence of failure in terms of the unique attributes of the asset.
Generally speaking, the process mechanical assets lend themselves the best to a criticality evaluation and is used
in this analysis
Through discussions and workshops four criticality criteria were developed to capture the range of potential impact
on the facility. These include:
• Capacity Affected – How much of the facility’s capacity is lost due to the asset failure.
• Water Quality/System Impact – To what extent is the water quality or overall operations of the facility
affected due to the asset failure.
• Redundancy – To what extent are there supporting assets that can provide the same service in the event
of an asset failure.
• Outage Duration – How long is the asset or the asset’s function out of service in the event of a failure.
A rating scale was developed to define the varying levels of severity for each of the criteria as shown in Table 4-3
below.
Table 4-3. Criticality Scale
Score Capacity Affected Water Quality/ System
Impact
Redundancy Outage Duration
Weighting 50% 25% 15% 10%
1 5% or less lost
capacity
Mild Impact on
Operations
Full Backup 1 day or less
2 5% to 10% lost
capacity
Operational Hindrance/
Loss of efficiency
Partial Backup 2 to 3 days
4 10% to 20% lost
capacity
Major Impact on
operations
Shared asset; Not
redundant
3 to 4 days
5 Greater than 20%
lost capacity
Missed water quality
goals
Dependent/No
backup
More than five days
The score for each criticality criterion is weighted by the factor shown in Table 4-3 to develop a single criticality
score from 1 (low impact) to 5 (high impact).
Once the condition and criticality scores have been determined they are multiplied together to determine the
Business Risk Evaluation (BRE) score. The BRE scores range from 1 to 25 with a score of one representing a low
probability and consequence of failure (a 1 on both scales) and a score of 25 representing a high probability and
consequence of failure (a 5 on both scales). Prioritization using the BRE scores follows the criteria in Table 4-4.
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Table 4-4. BRE Prioritization Criteria
BRE Score Action
20.0- 25.0 High Priority (within two years)
15.0 – 19.9 Priority (within five years)
0.0 – 14.9 Re-evaluate Condition in 5 years
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5.0 CONDITION ASSESSMENTS
5.1 ASSETS
Condition assessments were performed for the Lily Pond WTP assets based on visual inspections, discussions with
staff as well as available information on preventative and corrective maintenance activities. The on-site review
included a video log and photographs were taken to document existing conditions and operation. The condition
assessment forms are provided in Appendix C.
Asset discipline areas in the evaluation include:
1. Process Mechanical
2. Electrical
3. SCADA / Instrumentation
4. Structural
5. Architectural/Workplace Safety
6. HVAC
7. Site Civil / Security
Limitations for the on-site condition assessments included the following:
• A non-intrusive approach through visual inspection was used to assess the equipment. Tetra Tech did not
open or inspect operating equipment or that which was deemed unsafe.
• The condition assessments for Electrical/SCADA components did not include the following:
o Software licenses or hardware.
o PLC programs.
o Physical security or access control systems
• Visual inspection of confined spaces was limited to the following areas:
o Clearwell
o Sedimentation Basin 2 (Video of Sedimentation Basin 1 was reviewed)
o Flocculation Basins 1 and 2
o Mixing Basins 1 and 2
5.2 PROCESS MECHANICAL
Overall most components of the WTP are in good to average condition. There has been a history of maintaining
critical pieces of equipment, including replacing aging motors and gear boxes, actuators and routinely taking pumps
down in the low demand season for refurbishing.
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5.2.1 Intake Structure
Assets reviewed for the intake structure are shown in Table 5-1.
Table 5-1. Intake Structure Assets
Asset Condition Score Criticality Score Risk
Coarse Barscreen 1 (Left facing lake) 2 1.6 3.1
Coarse Barscreen 2 (Right facing lake) 2 1.6 3.1
Sluice Gate Inlet (Left) 2 1.0 2.0
Sluice Gate Outlet (Left) 2 1.0 2.0
Sluice Gate Inlet (Right) 2 1.0 2.0
Sluice Gate Outlet (Right) 3 1.0 3.0
Air Compressor 1 1.6 1.6
Overall the assets are in good condition with almost
all assets scoring a 1 or 2. A sump pump is installed
in each channel for draining but could not be
observed.
Major recommendations include:
• Repair of sluice gate which was observed to
be leaking.
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5.2.2 Raw Water Pumps
The assessment for the raw water pumps are shown in Table 5-2.
Table 5-2. Raw Water Pumps
Asset Condition Score Criticality Score Risk
Raw Water Pump 1 3 4.3 12.9
Raw Water Pump 2 1 4.3 4.3
Raw Water Pump 3 5 4.3 21.5
With all pumps operational there is sufficient capacity
to meet 3.0 MGD with one pump out of service. Raw
Water Pump 2 was installed in 2018 and is in good
condition. Pumps 1 and 3 were rebuilt and variable
frequency drives were installed on all pumps in 2012.
Pumps 1 and 2 are in routine operation and 3 is not
used or exercised and may not be operable. Check
valves on the discharge line for all pumps were
replaced in 2020.
Major recommendations include:
• Conduct an operational test on raw water
pump 3 and performing corrective
maintenance to bring it into the operational
rotation.
5.2.3 Rapid Mixers
The assessment for the rapid mixers are shown in Table 5-3.
Table 5-3. Rapid Mixers
Asset Condition Score Criticality Score Risk
Rapid mix baffles 5 3.6 17.8
Rapid mixer 1 3 4.1 12.2
Rapid mixer 2 3 4.1 12.2
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There is sufficient capacity in the mixing basins to
meet the 3.0 MGD capacity of the WTP with one unit
out of service. Rapid mixer 1 was observed from floor
level and appeared to be in average condition. Rapid
mixer 2 was in operation and submerged during the
site review. The motors for both mixers were replaced
in 2021 and the gear boxes were inspected and found
to be in good condition. The supporting bolts and
connections for the mixers are in poor condition.
The baffles in the mixing basins are in poor condition
with significant corrosion observed on the connection
bolts and plates.
Major recommendations include:
• Replace supports for both mixer units.
• Replace basin baffles.
5.2.4 Flocculators
The assessment for the flocculators are shown in Table 5-4.
Table 5-4. Flocculators
Asset Condition Score Criticality Score Risk
Paddle Assembly and Shaft 1 3 4.8 14.3
Paddle Assembly and Shaft 2 3 4.8 14.3
Flocculator Paddle Drive 1 1 4.7 4.7
Flocculator Paddle Drive 2 1 4.7 4.7
From the capacity analysis in Section 5 the flocculator
process can only marginally meet 3.0 MGD with both
units in service which increases its criticality score. The
flocculators were last maintained in 2013 and the motor
and gear boxes for both flocculators were replaced in
2019. The baffles are in good condition and the basin
drain valves and stems were replaced in 2019.
Major recommendations include:
• Continued monitoring of the flocculator units to
minimize the likelihood of an unexpected failure.
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5.2.5 Sedimentation Basin Equipment
The assessment for the sedimentation basin equipment is shown in Table 5-5.
Table 5-5. Sedimentation Basin Equipment
Asset Condition Score Criticality Score Risk
Chain/Flight 1 4 5.0 20.0
Chain/Flight 2 4 5.0 20.0
Baffles, Troughs, and Weirs 1 2 3.8 7.5
Baffles, Troughs, and Weirs 2 2 3.8 7.5
Tube Settler Basin 1 1 5.0 5.0
Tube Settler Basin 2 1 5.0 5.0
The sedimentation process is the limiting component of
the WTP. With both basins in service the effective
capacity of the basins is 2.8 MGD. There has been no
reported maintenance on the chain and flight sludge
scrapers since at least 2013 and due to the presence of
the tube settlers they were not visible during the site
review. The tube settlers were replaced in 2018 and are
in good condition and the baffles troughs and weirs are in
good condition.
Major recommendations include:
• Replace the chain and flight sludge scrapers.
• Replace the mid-level sludge valves
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5.2.6 Filters
The assessment for the filters is shown in Table 5-6.
Table 5-6. Filters
Asset Condition Score Criticality Score Risk
Surface Agitators, All Cells 3 2.0 5.9
Filter Media, All Cells 1 4.3 4.3
Underdrain System, All Cells 3 4.6 13.7
Troughs and Weirs, All Cells 3 1.5 4.5
Filter Backwash Pump 1 5 4.3 21.5
Filter Backwash Pump 2 2 4.3 8.6
Filter Valve Actuators 3 3.8 11.4
Blower (for Surface Agitators) 2 2.0 3.9
The filter media for all cell was replaced in 2020 and
during the replacement the filter underdrain was
inspected and damaged tiles replaced. The blower and
surface agitator system was installed around 2010.
During the site review filter backwash pump 2 was
pulled for maintenance and was found to be in poor
condition. The assumption by the team is the Pump 1
is in a similar condition.
WTP staff has been systematically replacing the motor
actuators on the filter backwash and discharge piping.
To date eight of the twelve actuators have been
replaced in the last five years.
Major recommendations include:
• Filter backwash pump 2 should be refurbished.
• The remaining valve actuators should be replaced in the short term starting with the actuator on the filter
discharge line which staff reports is likely 20 years old.
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5.2.7 Wastewater Pumps
The assessment for the filters is shown in Table 5-7.
Table 5-7. Wastewater Pumps
Asset Condition Score Criticality Score Risk
Wastewater/Sludge Pump 1 4 4.3 17.2
Wastewater/Sludge Pump 2 4 4.3 17.2
Grinder Pump Station 3 1.1 3.3
The wastewater/sludge pumps have no record of being
maintained, although it is recognized they operate under
light duty, mostly just for spent backwash water. WTP
staff indicate that these pumps are scheduled for major
rehabilitation in 2021.
The in-plant grinder station pumps to a pump station
located on-site external to the building.Major
recommendations include:
• Rehabilitate both wastewater sludge pumps
• Coordinate improvements to the in-plant grinder
pumps to coincide with removal of the yard pump
station.
5.2.8 Finished Water Pumps
The assessment for the finished water is shown in Table 5-8.
Table 5-8. Finished Water Pumps
Asset Condition Score Criticality Score Risk
Finished Water Pump 1 3 4.3 12.9
Finished Water Pump 2 3 4.3 12.9
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The finished water pumps are serviced annually and are
old but in good condition. VFDs were installed on the
pumps in 2012 and since that time the third jockey pump
is no longer used. The surge valve on the discharge
manifold was replaced in 2020.
Major recommendations include:
• Continued monitoring and maintenance of the
finished water pumps.
5.2.9 Sludge Lagoon
The assessment for the sludge lagoon is shown in Table 5-9.
Table 5-9. Sludge Lagoon
Asset Condition Score Criticality Score Risk
Sludge Lagoon 3 4.3 12.9
Recirculation Pump 3 4.0 12.0
Polymer System 2 2.3 4.5
Slide Gates 4 1.7 6.8
The sludge lagoon system in in overall average condition
and while it functions adequately to meet the current
needs of the WTP it is an expensive and inefficient means
of processing solids. The lagoons contained either sludge
or a geobag and could not be reviewed in detail.
Major recommendations include:
• Improvements are recommended to move to a
different sludge handling system (drying beds) to
improve system efficiency. This could be done in
conjunction with modifications to the sludge
decant water discharge to Lily Pond in response
to upcoming regulatory requirements.
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5.2.10 Plant Piping
The assessment for the plant piing is shown in Table 5-10.
Table 5-10. Plant Piping
Asset Condition Score Criticality Score Risk
24” Raw Water Line 3 4.9 14.7
Raw Water Pump Discharge 3 4.7 14.1
6” Rapid Mix and Flocculation Drain 3 2.3 6.8
6” and 8” Sed, Basin Sludge Piping 3 4.8 14.3
Surface Agitator Supply (Filter) 2 2.0 3.9
12” Filter Backwash Piping 3 4.9 14.7
16” Filter Discharge to Clearwell 3 5.0 15.0
12” Filer Drain Pipe 3 2.3 6.8
14” Finished Water Discharge 3 4.9 14.7
16” Wastewater Discharge 3 4.7 14.0
Grinder Station Discharge 3 2.5 7.4
A detailed review of the WTP piping is beyond the scope of this study. It appears, from external review the pipe in
general is in average condition, however, the bulk of the pipe is original with the plant and therefore, well into its
expected service life. The major process pipe throughout the facility represents single points of failure with no
redundancy as shown by the high criticality scores.
Major recommendations include:
• Conduct wall thickness testing on all critical process piping
• Replace the exposed corroded pipe at the chemical injection point between the filter and the clearwell.
• In conjunction with improvements to the in-plant grinder station, reroute the discharge piping so that it does
not run over the clearwell and finished water pumps.
5.2.11 Chemical Feed Systems
In general the chemical feed systems are in good condition with redundant pumps and storage. Table 5-11 presents
a summary of the evaluation.
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Table 5-11. Finished Water Pumps
System Asset Condition
Score
Criticality
Score Risk
Chlorine System (Pre and Post) Storage 2 1.8 3.5
Piping 2 4.6 9.2
Pump 1 1 4.1 4.1
Pump 2 3 4.1 12.3
Regulator 1 1 4.1 4.1
Regulator 2 1 4.1 4.1
Regulator 3 2 4.1 8.2
Ejectors 2 4.1 8.2
Scales 2 1.6 3.1
Ferric Chloride Pumps 2 3.8 7.5
Transfer Pump 3 1.9 5.6
Tanks 3 1.3 3.8
Piping 3 3.9 11.6
Sodium Hydroxide (Pre and
Post)
Pumps Tank 1 1 4.0 4.0
Pumps Tank 1 1 4.0 4.0
Transfer Pump 2 2.4 4.7
Pumps Tank 2 1 4.0 4.0
Pumps Tank 2 1 4.0 4.0
Day Tank 1 1 3.8 3.8
Day Tank 2 1 3.8 3.8
Bulk Tank 2 2.4 4.7
Piping 2 4.4 8.7
Polyaluminum Chloride Pump 1 2 4.0 8.0
Pump 2 2 4.0 8.0
Pump 3 2 4.0 8.0
Transfer Pump 2 2.4 4.7
Bulk Tank 2 2.2 4.4
Day Tank 2 3.2 6.4
Piping 2 4.4 8.7
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Table 5-11. Finished Water Pumps (Cont’d)
System Asset Condition
Score
Criticality
Score Risk
Sodium Permanganate Pump 1 2 4.0 8.0
Pump 2 2 4.0 8.0
75 Gallon Day Tank 3 4.4 13.1
250 gallon bulk tank 3 2.4 7.1
Piping 3 4.4 13.1
Polyacrylamide Polymer Feed Pumps 1 3.3 3.3
Transfer Pump 2 3.9 7.7
Storage 2 3.4 6.7
Piping 1 3.9 3.9
Ortho/Poly-phosphate/
Hexametaphosphate
Feed Pumps 2 4.0 8.0
Transfer Pump 3 4.4 13.1
Storage 2 1.3 2.5
Piping 2 4.4 8.7
Fluoride Bulk Tank 2 1.9 3.7
Piping 2 1.9 3.7
Pumps 2 1.3 2.5
In general, no major issues were found with the chemical
feed systems. There is space where the old lime feed
system was located that could be used for the ferric
chloride system.
Major recommendations include:
• Move the ferric chloride feed system from the area
by the door to the space previously occupied by
the lime system.
• Replace the chlorine system with a hypochlorite
system per the Town’s current plan.
5.2.12 Prioritization and Service Life
As mentioned in Section 5, the BRE score is the primary means of prioritizing the mechanical process projects.
Table 5-12 presents assets with the highest ranking BRE scores indicating a need for replacement within the next
5 years and the expected remaining service life based on the condition assessment.
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Table 5-12. Assets with Highest Ranking BRE Scores
Asset Condition
Score BRE Score Average
Service Life
Remaining
Service Life
Raw Water Pump 3 5 21.5 30 3
Filter Backwash Pump 1 5 21.5 30 3
Sedimentation Basin Chain/Flight (all) 4 20.0 30 9
Rapid Mix Baffles 5 17.8 30 3
Wastewater/Sludge Pumps (all) 4 17.2 30 9
Piping and Appurtenances 3 13.95-15.0 50 25
5.3 ELECTRICAL
5.3.1 Main Switchgear and Motor Control Center
In general, the overall condition of the main switchgear
and MCC compartments are in good shape. A
maintenance sticker on the main circuit breaker of
switchgear indicates that periodic maintenance/testing is
being performed on the critical components of the
electrical system. But similar maintenance tags or records
are not found for other MCC buckets for the rest of the
power system. Since the plant was in operation, it was not
possible to open any of the cubicles and perform a visual
inspection.
The cubicles are installed in the administrative area inside
the operator's daytime office room. This placement
restricted airflow above and behind the switchgear and
MCC compartments. Regulatory compliance does not
specifically ask for the clearance behind the panels, but it is
customary practice to keep sufficient space around electrical panels to maintain air flow around them. In case of Air
conditioning system failure in the office building space, the Switchgear and MCC panels will get warm very quickly.
Major recommendations include:
• The power distribution system for the overall plant needs to be redesigned within the next 10 years. The
control room housing the Main switchgear and Motor control centers need to be away from the office area
and beside machinery spaces, with adequate ventilation system in the room. Ideally a dedicated Rooftop
Thermal Unit (RTU) should be used for the Electrical room.
• Load Flow study and Arc Flash study are recommended for the plant electrical system. This is a
precautionary measure to take new electrical loads into account that were added to the plant over the years.
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5.3.2 Distribution Panels
In general, the condition of auxiliary power distribution panels and lighting distribution panels (mostly Eaton panels)
are in good condition shape.
5.3.3 Electrical and Instrumentation Cable Routing, Raceways
In general, the condition of Cable raceways including conduits, cable trays and other bracket supports in the process
areas are in good condition. In vehicle storage area in the outbuilding, some of the conduits for receptacles are
corroded near floor crossing. In the security server room all communication cables as well as power cables to
servers, modems, routers, UPS, and Fire alarm control panels are in bad shape.
Major recommendations include:
• Wiring in the security server room need to be completely rearranged. Communication and power cables
need to be segregated and streamlined to various devices in that room, so it is easier to do troubleshooting
when necessary.
• All auxiliary power conduits crossing floor levels need to be examined for corrosion. Corroded conduits
either need to be repaired or replaced within the next 5-year timeframe.
5.3.4 Transformers
Main Utility step down transformer for the plant located near the main entrance and front parking lot needs periodic
maintenance. Currently the front access to the transformer is blocked by trees/shrubs.
Transformer for lighting and auxiliary power is in decent shape.
Major recommendations include:
• Access area to the utility transformer need to be maintained as obstacle free for emergency access.
5.3.5 Grounding, Receptacles at Code Required Locations
In general grounding system in the plant is in good condition, where visible. Electrical power centers in the control
room could not be verified since the plant was in operation and parts were live at the time of site visit.
Majority of the receptacles are in undamaged shape. Some receptacles are worn out due to age, especially in the
intake structure and tank areas upstairs.
Major recommendations include:
• Replace worn out receptacles from various locations in the plant. Use Ground Fault Interrupter (GFI) type
where applicable and Weatherproof type for outdoor locations.
5.3.6 Lighting, Emergency Lighting
Lighting fixtures including emergency lights and exit lights in the plant are in good condition, with no observable
issues. Process areas have sufficient brightness for the operation. Emergency lights at random locations are tested
out and found operational.
Major recommendations include:
• Compressor room emergency light need to be replaced.
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5.3.7 Pump Motors, Variable Frequency Drives, Starters, Disconnects
Electric Motors for various pumps at the process area are in good condition.
Tags on the motors indicate that regular maintenance work are being
performed on them. Motors in the Flocculation tank area are corroded.
Variable frequency drives for Raw water pumps and High lift pumps are new
and in good condition. Some starters and disconnect switch assemblies in
the plant are in various stages of corrosion. Push button stations for
start/stop operation of heater fans in the tank area and disconnect switch
for sewer pump are examples of such corroded areas.
Major recommendations include:
• Corroded motors in tank areas, starter switches for unit heater
fans and disconnect switch for sewer pump should be replaced
within the next 5 years.
5.3.8 Pump Run Relays, Solenoid Valve Relays
VFD Run relays and Normal solenoid valve relays for High Lift pumps in the pump room are aged and worn out.
Major recommendations include:
• Replace the Run relays and Solenoid valve relays for High lift pumps in the pump room within the next 5
years.
5.3.9 Unit Heaters, HVAC Fan Motors, Aerator Fan
HVAC system units at various locations in the plant are corroded. Other Electrical equipment and devices are
generally in good condition.
5.3.10 Generator, Automatic Transfer Switch for Generator
The existing automatic transfer switch needs an upgrade as the unit is old and replacement parts are difficult to
obtain.
Major recommendations include:
• A new Smart Transfer switch will ensure efficient power transfer and improve the availability of the plant in
case of a power outage. The Switch should be rated to handle interrupting current for the system.
• An updated short circuit study for the plant electrical system is also recommended. This will help verify the
Generator ratings and decide the rating for new components including the ATS that will be added.
5.3.11 Overhead Motorized Door Operators at Storage Areas in Outbuilding
Motorized door operators in the storage areas of outbuilding are in good condition, with no observable issues.
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5.3.12 Fire Alarm, CCTV, Security System
System maintenance schedule or test record for the Fire alarm, CCTV and security system control panels could not
be verified. CCTV cameras on light posts outside and in the premises are functional.
5.4 SCADA/INSTRUMENTATION
5.4.1 Factors Affecting Automation
In the control room PLC panel, there is an insufficient amount of spare I/O
slots available for additional signals in the future. Ideally there should be at
least 20% spare slots to be made available. Existing Allen Bradley SLC 500
PLCs are 20-year-old models which are becoming obsolete in terms of
response times, communication protocols and compatibility with newer
instruments and devices.
Major recommendations include:
• Additional Input/Output modules need to be installed and the PLC
program updated as soon as possible, to provide 20% spare
capacity of the PLC system.
• SLC 500 controllers are becoming obsolete and being replaced by
new upgraded versions. The improvement in processing times with
the new version of controllers will eliminate latency issues and vastly
improve the plant performance.
5.4.2 SCADA Network Devices
Currently the water treatment plant communicates with remote sites including 2 reservoirs, 2 storage tanks and 2
pumping distribution system locations. The feedback of data from these sites is processed through a SCADA system
that uses Comcast service connections and the internet. This is very impractical from a security point of view since
it opens the water system up to cyber-attacks.
The Auto Dialer in the PLC panel, Sensaphone does not give accurate readings for certain I/O’s according to the
operator’s feedback.
Wiring inside the control panel should be streamlined according to the type of signal. Current conditions are not
helpful for troubleshooting any specific machinery, equipment, or instrument.
These devices should be placed in a clean, well ventilated location.
Major recommendations include:
• Switch the data transmission system from a broadband internet access system to a closed licensed
frequency radio to reduce vulnerability.
• Remote access to the plant systems should be upgraded to a secure network and the user connection must
be via an encrypted VPN tunnel.
• Alarm settings for the Auto dialer need to be verified or the dialer needs to be replaced.
• A more reliable remote alarm system needs to be developed and installed to improve the reliability of
operation.
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5.4.3 Instrumentation
The Process Mechanical section above gives a detailed description of condition by systems. In general,
instrumentation at the plant is in fair condition.
Some of the actuators, for example on raw water line and in the filter gallery, are old and need to be upgraded.
These actuators are currently being replaced with newer models.
Major recommendations include:
• Instrumentation in several of the processes need to be replaced in the next 5 years.
5.5 STRUCTURAL
5.5.1 Water Treatment Plant Building Interior
All concrete walls and CMU walls were observed
to be in good condition at time of assessment. No
cracks were observed in the CMU walls; however,
some isolated cases of peeling paint were
observed on the exterior walls in the tank room.
Two crack repairs were observed in the pump
room: one crack was located at the southwest
corner of flocculation tank 1, while the second was
located at the southwest corner of sedimentation
tank 1. It appeared that both cracks had been
previously repaired using polyurethane grout. The
crack repair at the sedimentation basin was
observed to be dry at time of observations, while
the crack repair at the flocculation tank was
observed to be damp. Additionally, a small
concrete spall was identified at the north side of the
man door located within the storage/garage room.
Concrete floor slabs were observed to be in good condition at time of assessment. Supporting concrete beams and
columns were also observed to be in good condition. Additionally, aluminum grating over trenches was observed
to be in good condition. Likewise, the guard railing around the tanks in the tank room was observed to be in good
condition however it was noticed that some guard railing included a toe plate, and some did not. Toe plates were
specifically observed around the three filters. The monorail system located within the pump room was also
observed. No issues were identified with the monorail beam and hoist.
The precast double tees making up the roof framing were observed to be in good condition at time of assessment.
Supporting concrete beams and columns were also observed to be in good condition. Some staining due to water
intrusion was observed in the tank room; however it is understood that the roof has been recently replaced and that
all active leaks should have been addressed as this time.
Refer to the Architectural section for additional details.
Major recommendations include:
• Recommend monitoring the crack injections repair located at the southwest corner of Flocculation Tank 1
for changes. If the repair happens to develop active/noticeable leakage into the pump room space, then
additional injections may be required to re-seal the crack.
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• Recommend monitoring the crack injections repair located at the southwest corner of Sedimentation Basin
1 for changes. If the repair happens to develop active/noticeable leakage into the pump room space, then
additional injections may be required to re-seal the crack.
• Recommend that the concrete spall identified at the north side of the man door, located within the
storage/garage room, be repaired. Concrete spalls should be repaired using a polymer-modified repair
mortar.
5.5.2 Water Treatment Plant Building Exterior
Overall, the building exterior was observed to be in fair-to-good condition at time of assessment. Observations were
made from the ground surface only. No cracks were observed in the 4" veneer block; however, the veneer mortar
joints were observed to be in poor condition at multiple locations around the building due to deterioration caused
by weather exposure. Previous tuck-pointing repairs could be observed on several wall elevations. Additionally,
multiple precast concrete sills located below windows were observed to be in poor condition due to deterioration
caused by weather exposure. Dark brown staining was observed on the unloading dock slab, as well as a portion
of the block veneer, on the west side of the building. It is believed that the discoloration is due to permanganate
chemical leaking onto the building and slab during delivery and transfer of the chemicals. Additionally, concrete
spalls were identified on multiple concrete steps leading up to the unloading dock. Lastly, a short crack in the
unloading dock slab was observed at a guardrail post connection. It is speculated that the crack was cause by either
load impact to the guardrail post or freeze-thaw of water around the post connection. Refer to the Architectural
section for additional details.
Major recommendations include:
• All mortar joints in the CMU veneer
showing signs of deterioration should be
inspected for soft or loose mortar. If soft or
loose mortar is identified, it is
recommended that the joints be repaired
via routing and tuck-pointing with fresh
mortar. The mortar joints should also be
inspected for holes and tuck-pointed as
appropriate.
• It is recommended that all deteriorated
precast window sills be replaced or flashed
to prevent potential water intrusion into the
building.
• Recommend repairing all concrete spalls
identified on the unloading dock stairs located at the west side of the building. Spall repairs are
recommended to prevent further deterioration of the concrete and should be executed using a polymer-
modified repair mortar. The existing metal nosing on the stairs may have to be removed and replaced to
allow for the proper concrete repairs to be made.
• Recommend repairing the cracked concrete observed at a guardrail post connection to the unloading dock
slab. It is recommend that the concrete be repaired to prevent future spalling of the slab edge as well as to
secure the guardrail post connection.
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5.5.3 Water-tight Retaining Wall
The water-tight retaining wall is believed to be an underground concrete
seepage wall located approximately 85 to 90 feet north of the main water
treatment building. It is believed that this concrete wall was installed to act
as a barrier between the septic system for the building and the adjacent
forest. According to plant maintenance, the septic system is no longer used
and the treatment building now utilizes city sewer. The concrete wall is
believed to be approximately 100 feet long and protrudes above the
ground approximately 1 to 3 feet. The wall was observed to be in good
condition at time of assessment. Sporadic cracks and spalls were identified
along the length of the wall. All cracks and spalls were observed to be
minor. Previous concrete spall repairs could be observed at random points
along the length of the wall.
Major recommendations include:
• Recommend repairing all concrete spalls in efforts to restore the
original construction as well as increase the service life of the wall.
Concrete spalls should be repaired using a polymer-modified
repair mortar.
5.5.4 Intake Structure
The interior of the intake building appeared to be in
good condition at time of assessment. No cracks were
identified in the CMU walls. The wood roof framing
could be observed within the intake chamber room
only. No signs of water infiltration or discoloring of the
wood framing could be identified. Additionally, the
concrete floor and aluminum coverings all appeared
to be in good condition. No visible cracks or spalls
were observed in the concrete. Defer to Architectural
for additional details.
The exterior of the intake building appeared to be in
good condition at time of assessment. No
discontinuities or damages in the siding, roofing, or
flashing could be observed. Additionally, the concrete
wing walls located at the pond side of the structure
appeared to be in good condition. No visible cracks or spalls were observed in the concrete. Defer to Architectural
for additional details.
The (3) intake chambers were not entered, and observations were made from the floor level only. The concrete
making up the intake chambers was observed to be in good condition at time of assessment. No visible cracks or
spalls could be identified. Additionally, the aluminum access hatches and ladder rungs for the east and west intake
chambers appeared to be in good condition.
The coarse bar screens located at the pond side of the intake structure were observed to be in good condition at
time of assessment. No visible corrosion or any other deteriorations could be identified. Per the as-built drawings
for the intake structure, the (2) coarse bar screens are fabricated from aluminum.
There are no major structural recommendations for the intake structure at this time.
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5.5.5 Raw Water Well
The raw water well contained approximately 12" of
water in the bottom at the time of assessment. The
concrete making up the well was observed to be in
good condition. The concrete divider walls located
between the pump suction heads were also observed
to be in good condition. (1) crack was identified in the
roof slab near the access opening. The crack
appeared to hairline. No spalls were identified in the
Raw Water Well. Additionally, multiple aluminum
ladder rungs were observed to be missing near the
bottom of the well.
Major recommendations include:
• Recommend monitoring the crack observed
in the Raw Water Well roof slab near the
access opening for fluctuations in length or width.
If the crack becomes severe, a Structural Engineer should be notified so that proper recommendations for
repair can be made.
• The absence of several aluminum ladder rungs suggest that the rungs have reached or exceeded their
service life. It is recommended that the rungs be removed and replaced with an OSHA complaint fixed
ladder. The ladder should be fabricated from stainless steel material for corrosion resistance. Additionally,
the ladder should be equipped with a telescoping grab bar to assist with safe entry into the Raw Water Well.
5.5.6 Rapid Mix Basins
Rapid Mix Basin 1 (South): This rapid mix basin was observed
from the floor level only. The concrete making up the basin was
observed to be in good condition at time of assessment. No
visible crack or spalls could be identified. The protective paint
coating on the inside of the tank was observed to be bubbling
and peeling away from the concrete surface. Multiple bolts for
the mixer support structure were observed to be in poor
condition due to corrosion. Additionally, the baffle structure
located with the basin was observed to be in poor condition.
Rapid Mix Basin 2 (North): This rapid mix basin was observed
from the floor level only. The concrete making up the basin was
observed to be in good condition at time of assessment. No
visible crack or spalls could be identified. The protective paint
coating on the inside of the tank was observed to be bubbling
and peeling away from the concrete surface. Multiple bolts for
the mixer support structure were observed to be in poor
condition due to corrosion. Additionally, the baffle structure
located with the basin was observed to be in poor condition.
Major recommendations include:
• For both Rapid Mix Basins, it is recommended that all
deteriorated bolts and anchors be removed and replaced
with new hardware. All new bolts and anchor should be stainless steel for corrosion resistance.
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• For both Rapid Mix Basins, it is recommended that the wood baffle and corresponding clip angles and bolts
be removed and replaced. All new clip angles, bolts, and anchor bolts should be stainless steel for corrosion
resistance.
• For both Rapid Mixing Bains, it is recommended that all remnants of the existing paint coating system
covering the walls and floor be removed. The walls and floors should be re-painted with a coating system
selected by an Engineer and/or coatings specialist. It is recommended that the coating system within the
basins be maintained so that the concrete is properly protected against chemical attack. The new protective
coating system should be properly selected based on the chemicals that are present within the basins.
5.5.7 Flocculation Tanks
Flocculation Tank Influent Channel: The floor grating was not removed to view inside the channel. The concrete is
assumed to be in good condition based on the observations made in the rapid mix basins as well as the flocculation
tanks.
Flocculation Tank 1 (South): The concrete making
up this flocculation tank was observed be in good
condition at time of assessment. The concrete pier
supporting the mixing equipment was also
observed to be in good condition. No visible cracks
or spalls were identified with the concrete. The
protective paint coating on the inside of the tank
was observed to be bubbling and peeling away
from the concrete surface. Additionally, the
aluminum baffle wall located within the tank was
observed to be in good condition. No issues with
the baffle wall were identified.
Flocculation Tank 2 (North): The concrete making
up this flocculation tank was observed be in good
condition at time of assessment. The concrete pier
supporting the mixing equipment was also observed to
be in good condition. No visible cracks or spalls were identified with the concrete. The protective paint coating on
the inside of the tank was observed to be bubbling and peeling away from the concrete surface. Additionally, the
aluminum baffle wall located within the tank was observed to be in good condition. No issues with the baffle wall
were identified.
Major recommendations include:
• For both Flocculation Tanks, it is recommended that all remnants of the existing paint coating system
covering the walls and floor be removed. The walls and floors should be re-painted with a coating system
selected by an Engineer and/or a coatings specialist. It is recommended that the coating system within the
tanks be maintained so that the concrete is properly protected against chemical attack. The new protective
coating system should be properly selected based on the chemicals that are present within the tanks.
Additionally, the Flocculation Tank Influent Channel should be cleaned and re-painted with a protective
coating system.
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5.5.8 Sedimentation Basins
Sedimentation Basin Influent Channel: The floor
grating was not removed to view inside the channel.
The concrete is assumed to be in good condition
based on the observations made in the flocculation
tanks as well as sedimentation basin 2.
Sedimentation Basin Effluent Boxes: The sludge
effluent boxes were observed from the floor level
only. The concrete making up the boxes was
observed to be in good condition at time of
assessment. No visible cracks or spalls were
identified. The steel wall bracket supporting the
motor operator and floor stand at sedimentation
basin 1 was observed to be in poor condition due to
corrosion. The anchors mounting the steel wall
bracket at both sedimentation basins 1 and 2 were
observed to be in poor condition due to corrosion.
Sedimentation Basin 1 (South): This sedimentation basin was not entered due to the proper equipment not being
on site and allowing safe access into the basin. However, a video recording was provided of the basin following the
site visit. The basin concrete was observed to be in good condition. No visible cracks or spalls in the walls or floor
were observed.
Sedimentation Basin 2 (North): The sludge hopper located at the west end of the basin was not entered. The
concrete making up this sedimentation basin was observed to be in good condition at time of observations. No
visible cracks or spalls were identified. Additionally, the metal framing supporting the tube settler system was
observed to be in good condition. No issues with the support framing was identified.
Major recommendations include:
• For both Sedimentation Basin Effluent Boxes, it is recommended that that existing steel bracket supporting
the motor operator and floor stand be replaced. It is recommended that the new bracket be fabricated of
stainless steel material for corrosion resistance. The anchors for mounting the bracket to the wall should
also be replaced with new stainless steel anchor bolts. The new bracket and anchor bolts should be
designed by a Structural Engineer to support the motor operator and floor stand loads.
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5.5.9 Filters
Filter Influent Channel: The concrete making up the
filter influent channel was observed be in good
condition at time of assessment. No visible cracks or
spalls were identified.
Filter 1 (West): This filter was filled with water and filter
media at time of observations. Observations were
made from the floor level only. The concrete that was
visible appeared to be in good condition. (1) crack was
observed in the east wall of the filter tank, just below
the CMU wall. The crack appeared to have been
previously repaired.
Filter 2 (Middle): This filter was filled with water and
filter media at time of observations. Observations
were made from the floor level only. The concrete that
was visible appeared to be in good condition. No cracks or spalls were identified.
Filter 3 (East): This filter was filled with water and filter media at time of observations. Observations were made from
the floor level only. The concrete that was visible appeared to be in good condition. (1) crack was observed in the
west wall of the filter tank, just below the CMU wall. The crack appeared to have been previously repaired.
Major recommendations include:
• Recommend monitoring the crack repairs identified in the concrete walls at Filters 1 and 3 for changes.
5.5.10 Clearwell
The clearwell sump area contained
approximately 2 feet of water at time of
assessment. The concrete making up the
clearwell was observed to be in good condition.
The concrete divider walls located between the
pump suction heads were also observed to be in
good condition. Sporadic cracks were observed
throughout the clearwell and were primarily
identified in the perimeter walls, roof beams, and
roof slab. All cracks appeared to be hairline. No
concrete spalls were identified in the Clearwell.
Additionally, multiple aluminum ladder rungs
were observed to be missing near the bottom of
the clearwell sump. Multiple threaded rod
anchors attaching the fabric baffle walls to the
concrete framing were observed to be
compromised due to corrosion.
Major recommendations include:
• Recommend monitoring the cracks observed in the Clearwell walls, roof slab, and roof beams for
fluctuations in length or width. If the cracks become severe, a Structural Engineer should be notified so that
proper recommendations for repair can be made.
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• The absence of several aluminum ladder rungs suggest that the rungs have reached or exceeded their
service life. It is recommended that the rungs be removed and replaced with an OSHA complaint fixed
ladder. The ladder should be fabricated from stainless steel material for corrosion resistance. Additionally,
the ladder should be equipped with a telescoping grab bar to assist with safe entry into the Clearwell.
• It is recommended that all missing or deteriorate anchor bolts attaching the fabric baffle walls to the concrete
framing be replaced with new anchor bolts. All new anchor bolts should be stainless steel for corrosion
resistance.
5.5.11 Wastewater Sump
The lower sump area contained approximately 1 to 2 feet of water and sediment at the time of assessment. The
lower sump area was not entered. The concrete making up the wastewater sump appeared to be in good condition.
Sporadic cracks were observed at the bottom face
of the roof slab. All cracks in the slab appeared to
be hairline. No spalls were identified in the
Wastewater Sump. Additionally, a substantial
amount of "chemical" build-up was observed at
the northwest corner of the sump, just below the
top slab. Plant maintenance clarified that lime was
originally discharged into the sump at this location
and that the process is no longer used.
Major recommendations include:
• Recommend monitoring the cracks
observed in the Wastewater Sump roof
slab for fluctuations in length or width. If
the cracks become severe, a Structural
Engineer should be notified so that proper
recommendations for repair can be made.
5.5.12 Vehicle Storage and Generator Building Interior
Walls: No cracks were observed in the CMU walls. Water staining was observed along the back/west wall of the
vehicle storage building. Paint was also observed to be peeling from this wall, especially where water staining was
visible. Additionally, efflorescence was observed on the interior face of the CMU block where paint was peeling
away. Similar conditions were also observed at the CMU jambs located between garage doors. In addition to the
peeling paint and efflorescence, the mortar joints at the door jamb locations showed signs of deterioration. The
water staining, peeling paint, efflorescence, and deteriorated mortar joints all suggest that moisture is seeping
through the CMU block wall.
Floor: The concrete floor slab was observed to be in good condition at time of assessment. A few minor shrinkage
cracks were visible in the slab. No major spalling was identified.
Roof Framing: The roof framing was observed to be in good condition at time of assessment. Corrosion was
identified along a joist bearing angle, located at the top of the back/west wall, near the northwest corner of the
building. The corrosion in this area suggest that water is leaking in from the roof level. Additionally, it should be
noted that the interior CMU partition wall separating the original generator room from the garage was removed at
some point and the generator room no longer exist.
Refer to the architectural for additional details
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Major recommendations include:
• It is recommended that the roof leakage identified at the back/west wall of the building be investigated and
repaired as appropriate to prevent further water infiltration into the building. The corrosion observed on the
joist bearing angle at this location should be properly removed and the steel cleaned and re-painted.
• The deteriorated mortar joints observed at the garage door jambs should be inspected for soft or loosed
mortar. If soft or loose mortar is identified, it is recommended that the joints be repaired via routing and
tuck-pointing with fresh mortar.
5.5.13 Vehicle Storage and Generator Building Exterior
Overall the building exterior was observed to be
in fair condition at time of assessment.
Observations were made from the ground surface
only. No cracks were observed in the 4" veneer
block. Water staining was visible on all wall
elevations, suggesting water leakage from the
roof level. Efflorescence was also observed in a
majority of the veneer mortar joints along the west
and south wall elevations. The efflorescence
suggest that water is infiltrating the wall and
moisture is getting trapped within cavities. The
mortar joints were observed to be in poor
condition at multiple locations around the building
due to deterioration caused by weather exposure.
Previous tuck-pointing repairs could be observed
on several wall elevations. Additionally, concrete
spalling was identified on the foundation wall, at the
southwest corner of the building, near ground level. Defer to Architectural for additional details.
Major recommendations include:
• It is recommended that any water leakage onto the building veneer from the roof level be addressed in
efforts to slow deterioration of the veneer mortar joints as well as to prevent further water infiltrating into the
building.
• All mortar joints in the CMU veneer showing signs of deterioration should be inspected for soft or loose
mortar. If soft or loose mortar is identified, it is recommended that the joints be repaired via routing and
tuck-pointing with fresh mortar. The mortar joints should also be inspected for holes and tuck-pointed as
appropriate.
• After the appropriate tuck-pointing repairs have been made to the veneer mortar joints, it is recommended
that the CMU veneer be coated with a water repellant system in efforts to prevent moisture intrusion through
the building veneer and walls. The water repellant coating system should be selected by an Engineer and/or
a coatings specialist. It should be noted that the water repellant coating will need to be maintained over the
life of the structure if moisture intrusion is to be controlled.
• Recommend repairing the concrete spall identified on the foundation wall at the southwest corner of the
building. Concrete spalls should be repaired using a polymer-modified repair mortar.
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5.5.14 Lagoon Structures
Lagoon Inlet Structure: The lagoon inlet structure was filled with water at time of assessment. The existing grating
at the top of the structure was not removed to view inside the chambers. Externally the concrete and grating cover
appeared to be in good condition at time of observations. No visible cracks or spalls were identified.
Lagoon Outlet Structures: The existing grating at the top of the outlet structures was not removed to view inside the
chamber. Externally the concrete, grating cover, and guard railing appeared to be in good condition at time of
observations. No visible cracks or spalls were identified.
Lagoon Bypass Channel: The lagoon bypass channel was filled with water at time of assessment. The existing
grating along the top of the structure was not removed to view inside the channel. The concrete and grating cover
appeared to be in good condition at time of observations. No visible cracks or spalls we identified.
Lagoon Concrete Lining: Visible cracks were
observed in the concrete lining around the
perimeter of the lagoons. Multiple cracks
appeared to have been repaired at some point
during the life of the lining. Cracks appeared to
have been repaired via routing and sealing with
polyurethane sealant. Some sealant was
observed to be deteriorated. New cracks
appeared to have formed since repairs were
last made.
Major recommendations include:
• Recommend draining both lagoons
and routing and sealing all cracks in
the concrete lining. Any visible
concrete spalls should be repaired at
this time as well. Such repairs will help
slow the deterioration of the concrete and improve watertightness of the lagoons. Cracks should be sealed
using an exterior grade polyurethane sealant. Concrete spalls should be repaired using a polymer-modified
repair mortar.
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5.6 ARCHITECTURAL/WORKPLACE SAFETY
5.6.1 WTP Building Exterior
The main roof of the Water Treatment Building was completed
in 2020. The lower level roof was completed a few years ago.
The main roof has a new white EPDM roof with walking pads.
There is some minor patching but in good condition.
The 12” CMU split face exterior walls (two wythe) with no air
space or insulation are in good condition, although the wall
system is not an efficient thermal envelope. This type of wall
assembly would not be permitted in Massachusetts under
today’s energy code requirements. There are some random
water stains along the exterior which might be due to failure in
the coping system.
Windows are single pane construction and should be replaced
in the future to a double pane system to improve the building’s
thermal efficiency. Some of the windows have been replaced
but remained single pane windows. About 10-20% of the
exterior caulking is cracked and broken down. Several
windows on the first and second floor are rusted, peeling and
have some water infiltration damage.
Effective weatherstripping should be evaluated at all door
types. Installed hardware functioning does not meet current code
requirements but there is not an immediate need to replace the hardware. Recommend as hardware fails,
replacement should meet ADA compliance.
The exterior radiator and mechanical louvers show visible signs of damage, including peeling paint and
discoloration. Exterior sealants are in fair condition. Control joints are functioning properly. Not immediately
necessary, but additional lighting should provide exterior illumination of the doors and accessways.
On the interior, main entrance hallways, control room and hallways of the second floor have 9” x 9” VCT tile that
most likely contain asbestos. The concrete floor treatment of some processing areas are peeling or completely
removed in locations. The CMU interior walls on the first and second floor are generally in good condition. The Lab
area on the second floor has countertops and cabinets that are in working condition and do not need to be replaced.
The countertops are particularly durable and look good, except for the around the sinks. Throughout the building,
installed hardware functioning does not meet current code requirements but there is not an immediate need to
replace the hardware. The ceiling stains are caused by a leak in the storm water system. The damage to the ceilings
in the building should be evaluated and could have been resolved with the new roof installation. The lighting
throughout the interior of the Water Treatment Plant facility is in good condition.
Major recommendations include:
• It is suggested that all the existing windows be re-sealed to maintain their thermal integrity.
• Door weatherstripping should be evaluated and replaced.
• Evaluate sinks (2) and pipe corrosion of the Lab area.
• It should be investigated if the ceiling damage is recent and continual. Demolition and installation of new
acoustical ceiling tile.
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5.6.2 Life Safety
In regard to life safety compliance, the Water Treatment Plant, does not have a fire suppression system. Fire
extinguishers were visibly noticed at the main entrance, office and pump room areas of the first floor, as well as the
Chemical Room and Chlorine Rooms on the second floor. Other process areas should provide a fire extinguisher.
Based on code, there should be a fire extinguisher at each egress door of the facility.
On the exterior, the second floor entrance into
the building on the East elevation has an
unleveled asphalt walkway and broken handrail
that needs to be addressed. According to ANSI
(American National Standards Institute) and the
ADA (American disabilities Act) guidelines there
are some concerns with accessible
route/entrance, parking and signage. The main
entrance to the building has a step to the
entranceway and does not provide handicap
access. A ramp would also need to be provided.
Within the vestibule, the length of the space
would have to be extended to 7 feet to
accommodate the length of a wheelchair and
the length of an inward door swing.
Exterior grading to the entry should also be
evaluated. A handicap parking space is provided
and marked with a handicap sign, but the ground is not properly designated as a handicap space according to code.
In addition, if the parking lot accommodates 26-50 spaces, two handicap spaces should be provided. The number
increases for every 25 spaces. On the interior of the building at the entry, the office transaction window does not
have a portion at the ADA maximum required height of 34 inches. Handicap access is not a requirement in the other
spaces of the building, other than the main entrance, offices, conference room and restrooms. The Men’s and
Women’s restrooms are not handicap accessible. The rooms would need to be reconfigured to accommodate
wheelchair access and maneuverability. If the facility undergoes a major renovation, the non-compliant ADA issues
will need to be addressed.
The main egress doors of the WTP building are equipped with a closer and panic hardware. The door threshold
should maintain a ¼” height.
Major recommendations include:
• Based on code, there should be a fire extinguisher at each egress door of the facility.
• The exterior second floor entrance into the building on the East elevation has an unleveled asphalt walkway
and broken handrail that needs to be addressed. Railing replacement.
• There should be an emergency alarm system at each floor.
• Chemical rooms should be investigated to check for eyewash station locations and availability. New
eyewash stations should be installed throughout the facility.
• Additional lighting should be installed at the vehicle storage and generator room as well as the raw water
intake building.
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5.6.3 Vehicle Storage and Generator Room
The interior concrete floor of the Vehicle Storage and Generator
Room shows removal of the protective coating in random areas. It
should be considered that the floor be re-sealed, but it does not
affect the function of the building. The CMU walls have some light
peeling but not a major concern. It was mentioned during the site
assessment that ventilation in the building is limited. It is
recommend that as hardware fails, replacement should meet ADA
compliance. Exposed ceiling joists and metal roof show some
minor paint peeling caused from heat, moisture or a combination
of both. Lighting throughout the interior of the building is
untarnished and efficient. The exterior of the building is 12” split
face CMU block. There is efflorescence showing on the exterior
meaning moisture is present in the wall system. There are no
windows or glazing conditions in the building. The louvers on the
exterior show slight wear and tear and visible signs of water
dripping onto the exterior from the lower portion of the louvers.
Sealants around the doors and louvers are in fair condition and
should be evaluated for efficiency. Exterior lighting is minimal.
Major recommendations include:
• The roof coping should be evaluated for intermittent cracks
allowing water to access the exterior of the building.
• The weatherproofing of the overhead doors should be checked, similar to the main building. ($500.00)
• The louvers on the exterior show slight wear and tear and visible signs of water dripping onto the exterior
from the lower portion of the louvers. ($1,000.00)
5.6.4 Raw Water Intake Building
The Raw Water Intake building was more recently constructed. The concrete floors are in good condition. The CMU
walls do not need repair or resurfacing. Door hardware is upgraded, including lever handles. No issues that need
to be resolved at this time. The function of this building does not require handicap accessibility. The windows and
window sealant are functioning properly. Exposed wood ceiling structure is in good condition. Wood construction
can show future effects of heat, moisture or a combination of both. The amount of artificial light is minimal and could
be increased. Wood siding has slight cracking damage, but overall in good condition. No water damage. Wood
siding does require future maintenance. The roof is in good condition. During the site assessment, it was noted that
the roof is new and well documented. The louvers are fairly new and do not show deterioration.
Major recommendations include:
• There are no major recommendations for the raw water intake building, except for the installation of lighting.
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5.7 HVAC
5.7.1 WTP Building
In general, the majority of the HVAC systems were
observed to be in fair to poor condition purely due
to the age of the equipment. The existing self-
contained units serving the administration space
are old and past the anticipated service life and
should be upgraded with a system that provides
better air distribution to the zones. The hydronic
system is operational however is past the service
life of the equipment and the distribution system
itself is showing signs of failure. Ventilation and
dehumidification systems serving the process
area are old and past the service life. Air
distribution systems including ductwork and
registers are showing signs of failure including
tears in insulation, rusted supports, and damage,
and should be replaced.
Major recommendations include:
• It is recommended that the HVAC system be replaced in its entirety as soon as possible due to the imminent
failure of equipment. This includes all-new air conditioning equipment, ventilation/ dehumidification systems
for the process area, restroom ventilation systems, and hydronic systems. For the occupied conditioned
spaces, the revised HVAC system should include better air distribution to the zones including upgrading
the ventilation airflow to the latest code requirements.
5.7.2 Plumbing
The water heater serving the building is 14 years old and is
likely approaching the end of its useful life. The water
distribution systems, cold and hot, are original and were
observed with wear, torn insulation, and rusted supports. It did
appear that leaks had developed in the ceiling tiles of the
building indicating possible leaks. The water distribution system
and generation system should be replaced.
Major recommendations include:
• All aboveground plumbing systems should be replaced
in their entirety due to the age of the equipment.
• Fire Protection: No sprinkler system was provided in
the building. When alterations are performed, an
analysis should be conducted on whether or not a
sprinkler system is required.
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5.7.3 Intake Structure
In general, the majority of the HVAC systems were observed to be in fair to poor condition purely due to the age of
the equipment. The existing split system serving the electrical equipment is 14 years old and due to the continuous
operation of the unit due to heat from electrical gear, these units should be replaced. The exhaust fans and unit
heaters serving the space are original and should be replaced as well.
Major recommendations include:
• It is recommended that the HVAC
system be replaced in its entirety over
the next 5 years or as-needed based
upon equipment failure. This includes
new air conditioning equipment for the
electrical room as well as ventilation
and heating systems for the process
area.
• Plumbing: No plumbing in this building.
• Fire Protection: No sprinkler system in
this building.
5.7.4 Vehicle Storage and Generator Room
The existing gas-fired unit heater serving the storage area is is past its median service life of 13 years and should
be replaced. No ventilation system was provided for the vehicle storage which should be upgraded to meet the
latest mechanical codes.
Major recommendations include:
• It is recommended that an all-new ventilation system be provided following the latest mechanical codes
include a ventilation system while the building is occupied and new heating systems. Currently, no
ventilation system is provided in this building. When the generator is replaced, it is recommended that a
new vent silencer and exhaust piping be provided due to the age of the existing equipment.
• Plumbing: No plumbing in this building.
• Fire Protection: No sprinkler system in this building.
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5.8 SITE CIVIL/SECURITY
5.8.1 Site Paving
Site paving is in poor condition and well past the expected service life. Significant pavement cracking was evident
throughout the facility pavement. Minor potholes were observed, but no wide spread evidence of base or sub-base
failure was noted. A condition score of 5 would be assigned but the existing pavement is still operable to the mission
of the site.
Major recommendations include:
• Pavement should be replaced (milled and
overlayed) with new pavement structure.
Based on the pavement condition of the
overall pavement, it does not appear that the
base and sub-base will need to be replaced
but a geotechnical analysis should be
conceded in each access area to verify the
depth of the base and stability of the sub-
base to determine whether they are
acceptable for continued use. The wearing
surface of the pavement is well past the
normal service life a simple pavement rehab
would not provide a significant improvement
to the roadway conditions.
5.8.2 Site Security
Very minor site security exists at the plant site. One
manual gate with a non-functional card reader was
noted, but based on information provided and site visit
observations, the site is open to the public for parking
and dog walking. Fencing for the public source surface
water is not consistent or has been bypassed around
the pond. The site seems to share the parking at this
site with the adjacent walking trail, and dog walkers
are normally walking the site near the intake of the
facility.
Major recommendations include:
• A full fence should be constructed around the
water facility, with chain-link fencing around
the plant and barbed wire (at a minimum
should be installed where existing breaches
exist). Access control to the site should be
limited to operators and approved Town
departments.
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5.8.3 Site Grading
The site grading was in good condition. Minor erosion occurs in area where the pavement discharges to the lake
and some minor erosion was noted near the inlets. Vegetation and trees have not been maintained at the outfall, in
one case a 6” tree blocks the 12” outfall pipe.
Major recommendations include:
• Site maintenance should be conducted on a yearly basis to correct minor erosion areas and replace or
augment riprap areas. Maintenance should also include the removal of woody vegetation at each outfall
and re-establish any grass around the discharge points. Some site flumes should be installed in areas
where stormwater is concentrated in flow.
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6.0 CAPITAL IMPROVEMENTS PLAN
6.1 DESCRIPTION OF PROJECTS AND COSTS
The recommended improvement projects for the Lily Pond WTP were organized based on the following disciplines:
process mechanical, electrical, SCADA/instrumentation, structural, architectural/workplace safety, HVAC, and site
civil upgrades and are recommended to occur within a twenty-year planning period. The improvements plan further
breaks the projects into 5 year increments, based on the criticality and condition assessment of the assets. An
estimate of probable cost was prepared for the recommended capital improvements.
The estimate of probable cost (EOPC) was prepared for the recommended capital improvements in five-year
intervals over the twenty-year planning period. The cost estimates were prepared in 2021 dollars and represent
planning-level estimates developed using cost curves, vendor-based estimates, and local and regional cost
estimate and schedules of values for similar type work and experience with analogous systems. Unit costs
developed include the cost of labor and materials, demolition, restoration, general requirements, contractor
overhead and profit, and any other such costs that are relevant to each specific proposed project.
All costs include a factor of 15% of the project cost for preliminary design, engineering, and permitting. In addition,
all costs have a 30% contingency factor to account for the level of project definition, variability in the contracting bid
market, and other unforeseen costs.
For the process mechanical asset recommended improvements, a total of 19 projects were identified which are
presented in Table 6-1.Out of the 19 projects identified, 6 are recommended to occur within the next 5 years, with
4 projects recommended within the next two years. The most critical improvements recommended within a 2 year
time frame include replacement of rapid mix baffles, replacement of the chain and flight collection system in the
sedimentation basin, and repair/refurbishment of filter backwash pump no. 2 and the raw water pump no. 3.
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Table 6-1. Process Mechanical Recommended Improvements, Timelines, and EOPC
Location Project
ID Project Description Project
Timeline EOPC ($2021)
Rapid Mix
Basin P-1 Replace rapid mix baffles Within 2 Years $55,000
Sedimentation
Basin P-2 Replace Chain & Flight Collection System,
Sludge Valves Within 2 Years $839,000
Filters P-3 Refurbish filter backwash pump no. 2 Within 2 Years $50,000
Raw Water P-4 Repair raw water pump no. 3 Within 2 Years $30,000
Wastewater P-5 Refurbish wastewater sludge pumps Within 5 Years $61,000
Plant Piping P-6 Replace filter water piping to clearwell
(chemical injection point) Within 5 Years $35,000
Filters P-7 Replace filter valve actuators Years 6-10 $40,000
Wastewater P-8 Replace grinder pumps and discharge
piping Years 6-10 $37,000
Sludge Lagoon P-9 Replace sluice gates between lagoons Years 6-10 $38,000
Chemical Feed
Systems P-10
• Replace ferric chloride storage tank,
transfer pump, and piping
• Replace sodium permanganate day
tank, bulk storage tank, and piping
• Replace ortho/polyphosphate/
mexametaphosphate transfer pump
Years 6-10 $115,000
Intake Structure P-11 Replace both sluice gates at inlet, right
sluice gate at outlet, and air compressor Years 11-15 $233,000
Raw Water P-12 Replace raw water pump no. 1 Years 11-15 $140,000
Rapid Mix
Basin P-13 Replace both rapid mix basin mixers Years 11-15 $161,000
Flocculation P-14 Replace paddle assembly and shaft Years 11-15 $109,000
Filters P-15 Replace filter surface agitator, underdrain
system, and launders & weirs Years 11-15 $1,018,000
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Table 6-1. Process Mechanical Recommended Improvements and Timelines (Cont’d)
Location Project
ID Project Description Project
Timeline EOPC ($2021)
Finished Water P-16 Replace high service pumps Years 11-15 $361,000
Sludge Lagoon P-17 Replace sludge recirculation pump and
polymer system Years 11-15 $165,000(1)
Chemical Feed
Systems P-18
• Replace ferric chloride feed pump
• Replace sodium hydroxide transfer pump,
bulk storage tank, and piping
• Replace polyaluminum chloride system
• Replace sodium permanganate feed
pump
• Replace polyacrylamide polymer storage
and transfer pump
• Replace
ortho/polyphosphate/mexametaphosphate
storage, chemical feed pump, and piping
• Replace fluoride storage tank, pump, and
piping
Years 11-15 $393,000
Chemical Feed
Systems P-19
• Replace sodium hydroxide day tank and
tank pump
• Replace polyacrylamide polymer chemical
feed pump and piping
Years 16-20 $108,000
Notes:
(1) Improvements to the solids handling facilities mentioned in Section 6.2 may eliminate this project.
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For the electrical and SCADA/instrumentation recommended improvements, a total of 9 projects were identified
which are presented in Table 6-2. Out of the 9 projects identified, 6 are recommended to occur within the next 5
years. All electrical and SCADA/instrumentation improvements are recommended to take place within the next 10
years.
Table 6-2. Recommended Electrical and SCADA/Instrumentation Improvements, Timelines, and EOPC
Location Project
ID Project Description Project
Timeline EOPC ($2021)
WTP Building E-1 Update single line diagram, perform load
flow study and arc flash study.
Within 5 Years $100,000
Emergency
Generator
E-2 Replace automatic transfer switch. Within 5 Years $28,000
WTP Building E-3 Replace grounding and receptacles,
disconnects/safety switches, pump run
relays, and solenoid valve relays.
Within 5 Years $80,000
WTP Building E-4 Replace natural gas unit heaters. Within 5 Years $39,000
WTP Building E-5 Perform control system design, replace
PLC processor and accessories, replace
I/O modules and HMI panel
Within 5 Years $357,000
WTP Building E-6 Perform SCADA system design including
cybersecurity and install new network
devices
Within 5 Years $443,000
WTP Building E-7 Redesign electrical room, install new
switchgear and new MCC.
Years 6-10 $732,000
WTP Building E-8 Install new cable routing and raceways.
Replace lighting.
Years 6-10 $34,000
WTP Building E-9 Provide new rooftop HVAC unit and
aerator fan.
Years 6-10 $67,000
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The structural improvements identified are recommended to take place within the next 10 years. A total of 10
projects were identified which are presented in Table 6-3. .Out of the 10 projects identified, 7 are recommended
to occur within the next 5 years totaling approximately $133,000.
Table 6-3. Recommended Structural Improvements,Timelines, and EOPC
Location Project
ID Project Description Project
Timeline EOPC ($2021)
WTP Building S-1
Crack injection and concrete spall repair,
window sill replacement, and guardrail
connection repair.
Within 5 Years $50,000
Raw Water Well S-2 Installation of new stainless steel ladder and
safety post in raw water well. Within 5 Years $6,000
Rapid Mix Basin S-3
New structural bolts and chemical/epoxy
anchors. Remove existing paint coating and
apply new protective coating system.
Within 5 Years $16,000
Flocculation
Tanks S-4 Apply new protective coating system Within 5 Years $28,000
Sedimentation
Basin S-5 Remove and replace existing bracket for
motor operator & floor stand Within 5 Years $7,000
Clearwell S-6 Replace existing aluminum ladder Within 5 Years $6,000
Vehicle Storage
Building S-7
Repair steel framing and mortar and perform
concrete spall repairs. Apply water repellant
coating.
Within 5 Years $20,000
Water-Tight
Retaining Wall S-8 Concrete spall repair of the water-tight
retaining wall Year 6-10 $5,000
Clearwell S-9 Repair chemical/epoxy anchors Year 6-10 $7,000
Lagoon
Structures S-10 Grout cracks in concrete lining and perform
shallow-depth spall repairs Year 6-10 $91,000(1)
Notes:
(1) Improvements to the solids handling facilities mentioned in Section 6.2 may eliminate this project.
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The architectural and workplace safety improvements identified are presented in Table 6-4. A total of 11 projects
are recommended to occur within a 20 year time frame. Out of the 11 projects identified, 3 are recommended to
occur within the next 5 years totaling approximately $303,000.
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Table 6-4. Recommended Architectural/Workplace Safety Improvements, Timelines, and EOPC
Location Project
ID Project Description Project
Timeline
EOPC
($2021)
WTP Building A-1
Reseal windows, replace door
weatherstripping, install new ceiling tiles, and
replace sinks in lab area. Install fire
extinguishers, emergency alarm system on
each floor, and new eyewash stations.
Repair unleveled asphalt walkway on the
east elevation. Reseal block exterior.
Within 5
Years $236,000
Vehicle Storage and
Generator Room A-2 Repair roof coping, weatherstripping of
overhead doors, and repair exterior louvers.
Within 5
Years $57,000
Raw Water Intake
Building A-3 Add LED upgraded interior and exterior
lighting
Within 5
Years $10,000
WTP Building A-4
Replace roof coping system, windows,
exterior radiator and louvers. Repaint
flocculation and settling area and refinish
floor areas currently peeling. Provide
adequate lighting throughout WTP along the
path of egress on the 1st and 2nd floors.
Year 6-10 $206,000
Vehicle Storage and
Generator Room A-5 Reseal all doors and louvers Year 6-10 $3,000
WTP Building A-6
Replace ADA compliant laboratory cabinet
system, countertops in laboratory, door
hardware, and upgrade lighting
Years 11-15 $204,000
Vehicle Storage and
Generator Room A-7 Repaint interior walls and upgrade lighting Years 11-15 $23,000
Raw Water Intake
Building A-8 Replace exterior louvers Years 11-15 $1,000
WTP Building A-9
Repair and replacement of main and lower
roof systems. Reseal doors, windows, and
louvers. Repaint building interior.
Years 16-20 $325,000
Vehicle Storage and
Generator Room A-10 Replace door hardware and root system Year 16-20 $37,000
Raw Water Intake
Building A-11
Reseal concrete floors, repaint interior walls,
replace door hardware, and repair wood
siding
Year 16-20 $57,000
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The HVAC improvements identified are recommended to take place within the next 10 years. A total of 4 projects
were identified which are presented in Table 6-5. Out of the 4 projects identified, 3 are recommended to occur
within the next 5 years totaling approximately $311,000.
Table 6-5. Recommended HVAC Improvements, Timelines, and EOPC
Location Project
ID Project Description Project
Timeline EOPC ($2021)
WTP Building H-1
• Replace air handling units (3-5 ton)
• Replace hydronic boilers, cabinet
hydronic heaters, hydronic pumps, and
hydronic unit heaters
• Replace condensing unit and piping
• Replace split system dehumidifier
• Replace exhaust fans, concealed and
visible
• Replace 100 gallon expansion tank
• Replace self-contained AC units
• Replace HVAC piping and insulation, and
perform duct work
• Replace water heater and upgrade
general plumbing piping
• Replace emergency showers
Within 5 Years $252,000
Intake Structure H-2
• Replace split system unit (5 ton)
• Replace fans and dampers
• Replace electric unit heaters
Within 5 Years $19,000
Vehicle Storage
Building H-3 • Replace gas fired unit heaters
• Install new ventilation system Within 5 Years $40,000
Intake
Structure/Vehicle
Storage Building
H-4 General HVAC piping replacement and
insulation Years 6-10 $2,000
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The site civil/security recommended improvements identified are presented in Table 6-6. Three site civil projects
are recommended to occur within a 15 year time frame. Out of the 3 projects identified, 2 are recommended to
occur within the next 5 years totaling approximately $248,000.
Table 6-6. Recommended Site Civil/Security Improvements, Timelines, and EOPC
Location Project
ID Project Description Project
Timeline EOPC ($2021)
WTP Site C-1 Repave WTP site Within 5 Years $91,000
WTP Site C-2 Install security system with two gates Within 5 Years $157,000
WTP Pond C-3 Install security at ponds with four gates Years 11-15 $239,000
6.2 ADDITIONAL PROJECTS
The project identified in this report cover the necessary requirements to systematically replace aging facility
components to continue operations. Through the course of this analysis and parallel studies on the Lily Pond WTP
additional potential projects have been identified that either improve the efficiency of the WTP or are necessary to
meet upcoming regulatory requirements. A summary of each project is provided herein to provide a placeholder in
the CIP.
• GAC Units - The results of the Town of Cohasset Granular Activated Carbon (GAC) Pilot Study (Tetra
Tech 2020) recommended full scale facilities to reduce total trihalomethanes in the summer season when
higher total organic carbon and temperatures facilitate their formation.
• Sludge Handling Improvements – The current method of sludge handling while adequate has limited
dewatering capabilities and as a result disposal costs are high. Specific solutions to improve sludge
handling will be investigated in subsequent studies but at this time it is expected that the existing lagoons
will be replaced by sludge drying beds.
• Wastewater Recovery Improvements – Wastewater generated by filter backwashing is pumped to the
sludge lagoons and, along with the sludge supernatant, ultimately discharges to Lily Pond. MassDEP
revisions to aluminum criteria (see Section 3.4.3) are expected to require site specific aluminum discharge
limits that will become effective in the next NPDES permit cycle (6 to 7 years from 2021).
Potential options for addressing aluminum in discharge from the Lily Pond WTP that were discussed are
summarized as follows:
o Optimization of coagulant dose and usage.
o Evaluate the ability to connect to sewer to allow elimination of discharge to Lily Pond.
o Investigate groundwater discharge to a future unlined lagoon.
o Investigate potential for underground injection control (UIC) or groundwater discharge permit.
o Investigate modifying facility to allow for recycle of filter backwash to the head of the plant.
• Hypochlorite Improvements – The Town plans to replace the existing gas chlorination system with a liquid
hyrpochlorite feed system to improve safety and ease of handling.
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6.3 CAPITAL IMPROVEMENT PLAN
The recommended improvements for the Lily Pond water treatment plant include process mechanical, electrical,
instrumentation and control, structural, architectural, HVAC, and site civil upgrades within a twenty-year planning
period. The improvements plan provides a timeline recommending which projects to initialize based on the criticality
and condition assessment of existing assets. An estimate of probable cost was prepared for the recommended
capital improvements in five-year intervals over the twenty-year planning period. The cost estimates, prepared in
2021 dollars for all disciplines, are provided in Table 6-1 through Table 6-6. The opinions of probable costs
represent planning-level estimates developed using cost curves, vendor-based estimates, and local and regional
cost estimate and schedules of values for similar type work and experience with analogous systems. Therefore, the
CIP costs are intended for planning purposes only, as they do not represent design-based engineering estimates.
Unit costs developed include the cost of labor and materials, demolition, restoration, general requirements,
contractor overhead and profit, and any other such costs that are relevant to each specific proposed project.
All costs include a factor of 15% of the project cost for preliminary design, engineering, and permitting. In addition,
all costs have a 30% contingency factor to account for the level of project definition, variability in the contracting bid
market, and other unforeseen costs.
Table 6-7 summarizes the cost of all projects per five-year interval per discipline lumped together to provide a total
construction cost estimate that can be used for budgetary purposes.
In addition to the project identified in this report to renew and replace facility components as they age, other projects
have been identified that either improve the WTP efficiency, or are required to meet anticipated regulatory
requirements.
Table 6-7. Summary of CIP Projects
Within 5
Years Years 6-10 Years 11-15 Years 16-20 Total
Process Mechanical $1,070,000 $230,000 $2,666,000 $108,000 $4,074,000
Electrical &
SCADA/Instrumentation $1,047,000 $833,000 - - $1,880,000
Structural $133,000 $103,000 - - $236,000
Architectural/Workplace Safety $303,000 $209,000 $228,000 $419,000 $1,159,000
HVAC $311,000 $2,000 - - $313,000
Site Civil/Security $248,000 $239,000 - - $487,000
Total $3,112,000 $1,616,000 $2,894,000 $527,000 $8,149,000
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7.0 CONCLUSIONS AND RECOMMENDATIONS
Based on the review and analysis summarized herein Tetra Tech offers the following conclusions and
recommendations:
1. The Lily Pond WTP is old but in good to average condition. Projected improvements to the facility are based
on a condition assessment and, for the mechanical process equipment, a business risk evaluation. Table
7-1 provides a summary of the capital program for the Lily Pond WTP in 2021 dollars. This capital program
includes investments for renewal and replacements to maintain facility operation, planned improvements to
improve the safety and security of the facility, and expected projects to meet anticipated regulatory
requirements.
Table 7-1. Summary of CIP Projects
Within 5
Years Years 6-10 Years 11-15 Years 16-20 Total
Process Mechanical $1,070,000 $230,000 $2,666,000 $108,000 $4,074,000
Electrical &
SCADA/Instrumentation $1,047,000 $833,000 - - $1,880,000
Structural $133,000 $103,000 - - $236,000
Architectural/Workplace Safety $303,000 $209,000 $228,000 $419,000 $1,159,000
HVAC $311,000 $2,000 - - $313,000
Site Civil/Security $248,000 $239,000 - - $487,000
Total $3,114,00 $1,616,000 $2,894,000 $527,000 $8,149,000
2. A few projects were identified that were beyond the scope of this study. Placeholders have been entered
into the capital program for tracking purposes. Further evaluation is recommended and may substantially
alter the conclusions. These projects include:
a. The addition of GAC units to aid in trihalomethane control.
b. Improvements to the solids handling facilities.
c. Improvements to address the projected MassDEP aluminum discharge requirements to Lily Pond.
3. In addition to the capital program it is recommended the Town periodically conduct a condition assessment
on a three to five year cycle and update the capital program based on its results.
4. Based on the capacity analysis, the Lilly Pond WTP is limited to a maximum day capacity of 2.83 MGD at
the sedimentation basins assuming both basins are operational. The firm capacity of the facility, which
assumes one basin is out of service is 1.41 MGD. Additional limitations exist with the detention times in
the mixing and flocculation basins that could result in diminished treatment effectiveness.
5. Based on current projections the Town may need to apply for an increase in withdrawals from Lily Pond
beyond the current 0.95 MGD in the next few years.
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6. Although the system has interconnects with adjacent utility systems for emergency supply, it twas reported
by operations staff that there are concerns about the ability of the connections to to provide sufficient back
up while maintaining water quality in the system. The possibility of adding additional staorge in the system
could be considered to mitigate this concern.
7. In its current mode of operations of eight to 10 hours a day the WTP is experiencing performance issues
during peak flow times. It is recommended to extend the operating hours of the facility to reduce flow rate
through the plant to meet peak demands.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-1 200-121837-20003
APPENDICES
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APPENDIX A – MASSDEP DRINKING WATER STANDARDS AND GUIDELINES
Table A-1. Massachusetts Maximum Contaminant Levels (MMCL)
Substance MMCL, mg/L
Acrylamide Treatment Technique
Alachlor 0.002
Antimony 0.006
Arsenic 0.01
Asbestos 7 million fibers/liter
Atrazine 0.003
Barium 2
Benzene 0.005
Benzo(a)pyrene 0.0002
Beryllium 0.004
Bromate 0.01
Cadmium 0.005
Carbofuran 0.04
Carbon tetrachloride 0.005
Chloramines (as Cl2) 4.0 (MRDL)
Chlordane 0.002
Chlorine (as Cl2) 4.0 (MRDL)
Chlorine dioxide (as ClO2) 0.8 (MRDL)
Chlorite 1
Chlorobenzene 0.1
Chromium (total) 0.1
Copper Treatment Technique, 1.3 (Action Level)
Cyanide (as free cyanide) 0.2
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Substance MMCL, mg/L
2,4-D (2,4-Dichlorophenoxyacetic acid) 0.07
Dalapon 0.2
1,2-Dibromo-3-chloropropane (DBCP) 0.0002
1,2-Dichlorobenzene (o-DCB) 0.6
1,4-Dichlorobenzene (p-DCB) 0.005
1,2-Dichloroethane 0.005
1,1-Dichloroethylene 0.007
cis-1,2-Dichloroethylene 0.07
trans-1,2-Dichloroethylene 0.1
Dichloromethane 0.005
1,2-Dichloropropane 0.005
Di(2-ethylhexyl)-adipate 0.4
Di(2-ethylhexyl)-phthalate 0.006
Dinoseb 0.007
Diquat 0.02
Endothall 0.1
Endrin 0.002
Epichlorohydrin Treatment Technique
Ethylbenzene 0.7
Ethylene dibromide (EDB) 0.00002
Fluoride 4
Glyphosate 0.7
Haloacetic acids (HAA5) 0.06
Heptachlor 0.0004
Heptachlor epoxide 0.0002
Hexachlorobenzene 0.001
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-4 200-121837-20003
Substance MMCL, mg/L
Hexachlorocyclopentadiene 0.05
Lead Treatment Technique, 0.015 (Action Level)
Lindane 0.0002
Mercury (inorganic) 0.002
Methoxychlor 0.04
Nitrate (As N) 10
Nitrate/Nitrite (total) 10
Nitrite (As N) 1
Oxamyl (Vydate) 0.2
PCBs (Polychlorinated biphenyls) 0.0005
Pentachlorophenol 0.001
Perchlorate 0.002
Picloram 0.5
Selenium 0.05
Simazine 0.004
Styrene 0.1
2,3,7,8-TCDD (Dioxin) 3 x 10-8
Tetrachloroethylene 0.005
Thallium 0.002
Toluene 1
Total trihalomethanes (for chlorinated supplies only) 0.08
Including: Chloroform N/A [10]
Chlorodibromomethane N/A
Bromodichloromethane N/A
Bromoform N/A
Toxaphene 0.003
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-5 200-121837-20003
Substance MMCL, mg/L
2,4,5-TP (Silvex) 0.05
1,2,4-Trichlorobenzene 0.07
1,1,1-Trichloroethane 0.2
1,1,2-Trichloroethane 0.005
Trichloroethylene 0.005
Vinyl chloride 0.002
Xylenes (total) 10
Notes:
a. MMCL = Massachusetts Maximum Contaminant Level; MRDL = Maximum Residual Disinfectant Level.
Table A-2. MassDEP Radionuclides MMCLs
Substance MMCL, pCi/L
Beta Particle and Photon Radioactivity Concentration which produces an annual dose of
4 millirem/year
Gross Alpha Radiation 1 15
Radium 226 and 228 5
Radon-222 2 10,000 (OSRG)
Uranium 0.030 mg/L
Notes:
(1) If gross alpha is equal to or greater than 5 pCi/L, testing for radium 226 and radium 228 is required.
If gross alpha is equal to or greater than 15 pCi/L, testing for uranium is required.
(2) Exceedance of this guidelines require indoor air sampling for Radon-222.
OSRG = MassDEP Office of Research and Standards Guidelines.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-6 200-121837-20003
Table A-3. MassDEP Biological MMCLs
Substance MMCL
Cryptosporidium Treatment Technique
E. Coli 310 CMR 22.05
Giardia Lamblia Treatment Technique
Heterotrophic Plate Count Treatment Technique
Legionella Treatment Technique
Turbidity Treatment Technique
Viruses (enteric) Treatment Technique
Total Coliforms 1 Indicator used in tiered monitoring protocol in the
Revised Total Coliform Rule.
Fecal Indicator (E. Coli, Enterococci, Coliphae) 2 Indicator used in tiered monitoring protocol in the
Ground Water Rule.
Notes:
(1) For additional information, refer to 310 CMR 22.05.
(2) For additional information, refer to 310 CMR 22.26.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-7 200-121837-20003
Table A-4. Massachusetts Office of Research and Standards Guidelines (ORSG)
Substance ORSG, mg/L
Acetone 6.3
Aldicarb 0.003
Aldicarb sulfone 0.002
Aldicarb sulfoxide 0.004
Bromomethane 0.01
Chloroform 0.07
Dichlorodifluoromethane 1.4
1,1-Dichloroethane 0.07
1,3-Dichloropropene 0.0004
1,4-Dioxane 0.0003
Ethylene glycol 14
Manganese General population:
0.3 (lifetime);
1.0 (limit exposure to > 1.0 mg/L to 10 days)
Infants < 1 yr old:
0.3 (limit exposure to > 0.3 mg/L to 10 days)
Methyl ethyl ketone 4
Methyl isobutyl ketone 0.35
Methyl tertiary butyl ether 0.07
Metolachlor 0.1
Naphthalene 0.14
Nickel [20] 0.1
n-Nitrosodimethylamine (NDMA) 0.00001
Petroleum hydrocarbons:
TPH
0.2
Aliphatics:
C5-C8 0.3
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-8 200-121837-20003
Substance ORSG, mg/L
C9-C12 0.7
C9-C18 0.7
C19-C36 14
Aromatics:
C6-C8 Use guidance for individual chemicals
C9-C10 0.2
C11-C22 0.2
PFAS1 0.00002
Sodium [24] 20
Tertiary-Amyl Methyl Ether (TAME) 0.09
Tertiary Butyl Alcohol (TBA) 0.12
Tetrahydrofuran [25] 0.6
1,1,2-Trichloro-1,2,2-trifluoroethane (FREON 113) 210
Note:
• Sum of six PFAS compounds: PFDA, PFOA, PFOS, PFNA, PFHxS and PFHpA.
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-9 200-121837-20003
Table A-5. MassDEP Secondary Maximum Contaminant Levels (SMCL)
Substance SCML, mg/L
Aluminum 0.05 to 0.2
Chloride 250
Color 15 Color Units
Copper 1
Corrosivity non-corrosive
Fluoride 2
Foaming agents 0.5
Iron 0.3
Manganese [27] 0.05
Methyl tertiary butyl ether [28] 0.020-0.040
Odor 3 threshold odor numbers
pH [30] 6.5 - 8.5
Silver 0.1
Sulfate 250 [31]
Total dissolved solids (TDS) 500
Zinc 5
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-10 200-121837-20003
APPENDIX B - PRIORITIZATION WORKSHOP
1
COHASSET WATER DEPARTMENT – COHASSET, MA
LILY POND WTP 20-YEAR CAPITAL IMPROVEMENT PLAN
PRIORITIZATION WORKSHOP – NOVEMBER 12, 2020 1:00 PM
A. Attendees via Microsoft Teams
a. Jason Federico, Town of Cohasset
b. Fred Rogers, Woodard & Curran
c. Carl Hillstrom, Woodard & Curran
d. Jonathan Loja, Woodard & Curran
e. Tetra Tech: Tony Omobono, Andy Woodcock, and Andrea Netcher
B. Prioritization Workshop Presentation
a. See Attached Presentation Slides
b. Review of Assets (See Attached Updated Asset List)
i. Architectural
1. The Town recently conducted an in-house safety Audit of the facility
and will share with Tt the findings report.
ii. Electrical and I&C
1. Town is planning for a SCADA project to increase Cyber security and
augment I/O.
2. Asset review will include general recommendations for improving
energy efficiency, but would not include an energy efficiency study.
iii. HVAC
1. The Town’s facilitator on energy efficiency is scheduled to visit facility.
The Town will plan on sharing any results and assessments from the
facilitator’s visit.
iv. Process
1. Filters
a. There is a blower that drives the surface agitators for the filters.
The blower is located outside the building and includes a
Lily Pond WTP 20-Year Capital Improvement Plan Workshop Meeting Minutes
2
stainless steel piping system to allow the air scour for bed
agitation. The stainless steel piping is underneath the media
and is not be visible for inspection.
b. Filter media was replaced last year.
c. The underdrain system (Roberts system style) was inspected
and rehabilitated last year. Some of the tiles were replaced.
Town has photos taken when the media was replaced.
Underdrain system will likely need to be replaced during the
next media replacement.
d. Filter header piping is currently being re-done.
e. Backwash water goes into a wastewater well and then is
pumped to the sludge lagoons.
2. There will be limited ability to asses the condition of piping above
ground. The assessment is limited to a visual inspection plus input
from on-site personnel.
3. Chemical Feed Systems
a. Chlorine and hydroxide systems have pre and post feed.
b. Hydroxide system includes 2 chemical tanks and 4 feed pumps.
c. Fluoride fed by a fluoride saturator system.
4. Rapid mix basins have two rapid mixers, each equipped with a motor.
5. Flocculation mixers also have their own sets of motors for mixing.
6. Chain/flight motors and scrapers to be grouped with Sedimentation
Basins.
v. Civil/Site
1. Facility is located within a residential community.
2. Site does not currently have controlled access and residents use plant
entrance to access pond area for recreation.
3. Asset review will include site access and security considerations.
vi. Structural
1. Matt Ulrich (Tt) will set-up call with Carl to coordinate confined space
entry.
Lily Pond WTP 20-Year Capital Improvement Plan Workshop Meeting Minutes
3
2. Sludge lagoon is used for sludge processing and drying. Two-cell
system, where the filter backwash enters the active side, is dosed with
polymer, and the supernatant is recycled to the plant. The sludge is
then transferred to the other cell of the lagoon for drying.
c. Site Review
i. For site visit, team will plan for a 30-minute pre-meeting with Tt, Town and
Operations.
ii. If possible, requesting to have personnel available to ask questions during the
walk through. Follow-up interviews can also be set-up to discuss any
questions.
iii. Structural Inspection Staging: Matt will be present on the first day and then
will come back for the next round when the process basins have been
switched over.
iv. Site Visit Available Dates: December 8, 9, 10 and 11th. The 9th was set as the
main inspection day with the 11th for the second day of structural evaluation.
v. The basins take about an hour to drain.
vi. Jason added filter internal pictures to the Teams site.
d. Prioritization Process
i. Water quality and compliance review to be completed with the condition
assessment.
ii. Recommend a 1 to 5 Condition score for simplicity
iii. Discussed whether criticality is more important than condition.
1. Criticality can be scored on a higher scale, such as 1 to 10 or as a
multiple of the base scale
iv. Condition
1. Condition scoring of 1 to 5 and descriptions were agreed to. Condition
Scale attached.
v. Criticality
1. Major critical component is impact on capacity loss as the Lily Pond
WTP supplies 80% of the drinking water to the Town.
2. During summertime, downtime becomes even more critical.
Lily Pond WTP 20-Year Capital Improvement Plan Workshop Meeting Minutes
4
3. Peaking factor is typically from 0.5 MGD to 1.5 MGD.
4. Design treatment capacity is 3.0 MGD. Typical treatment capacity is
2.0 MGD due to observed water quality performance.
5. Report will include description of the scoring guides and will include a
breakdown of the criteria.
6. Preliminarily selected the following scoring breakdown:
a. Capacity Affected: 50%
b. Water Quality/System Impact: 25%
c. Redundancy: 15%
d. Outage Duration: 10%
vi. Town will further evaluate criticality and weight scoring and will provide input
to Tt. Criticality scale to date is attached.
vii. When grouping asset rankings by process area, the assessment will breakout
the scoring by each component; therefore, if a component is identified as
critical, then the overall the overall process area is flagged.
C. Action Items
a. Tt to set up call with Carl to discuss confined entry (Scheduled for Friday (11/20) 10
am.) Item Completed.
b. Town to send Tt the Safety Audit Report from the in-house audit that was recently
completed.
c. Town to send Tt information on proposed SCADA project to increase Cyber security
and augment I/O. (Tt has received “Remote Access Options” summary). Item
Completed.
d. Town to provide count or identifiers for filter valve actuators.
e. Town to further evaluate criticality and weight scoring and provide input to Tt.
D. Attachments
a. Prioritization Workshop Presentation Slides
b. Asset List (Updated)
c. Condition & Criticality Scoring Spreadsheet
11/20/2020
1
Lily Pond WTP 20 Year CIP
Prioritization Workshop
TETRA TECH
Agenda
Review of Assets
Site Review Discussion
Prioritization Process
Condition Scale
Criticality Factors
2
1
2
11/20/2020
2
Separate Document
Review of Assets
3
TT Discipline Leads on-site
‒Process Equipment – Andy Woodcock
‒Electrical – Dave Berger
‒Structural – Matt Ulrich
Other Discipline Leads
‒Architectural – Quentin Biagi
‒Mechanical – Michael Sutherland
‒Site/Civil – James Warner
Set Dates/Times
Site Review
4
3
4
11/20/2020
3
Prioritize renewal and replacement activities using
two parameters
Likelihood of Failure – Asset Condition
‒What state is the asset in
Consequence of Failure – Criticality
‒If the asset fails how does it affect the operations of the
facility.
Condition X Criticality = Risk
Prioritize actions based on addressing the highest
risk first.
Prioritization Process
5
Subjective approach to evaluating condition and
criticality.
Develop condition and criticality scales
Condition estimated based on condition
assessment of identified assets
Criticality estimated based on discussions and
understanding of systems and processes.
Prioritization Process
6
5
6
11/20/2020
4
Criticality
Severe Significant Moderate
Low to
Moderate Low
54321
ConditionUn‐serviceable 5
Highest
Priority
Immediate
Action
High Priority
Program
Rehab
Priority
Program
Rehab
Priority
Program
Rehab
Priority
Program
Rehab
Renewal Required 4
High Priority
Program
Rehab
Priority
Program
Rehab
Priority
Program
Rehab
Frequent
Condition
Evaluation
Frequent
Condition
Evaluation
Maintenance
Required 3
Priority
Program
Rehab
Frequent
Condition
Evaluation
Frequent
Condition
Evaluation
Frequent
Condition
Evaluation
Regular
Monitoring
Minor Defects 2
Frequent
Condition
Evaluation
Frequent
Condition
Evaluation
Regular
Monitoring
Regular
Monitoring
Regular
Monitoring
Very Good 1 Regular
Monitoring
Regular
Monitoring
Regular
Monitoring
Regular
Monitoring
Regular
Monitoring
Prioritization Risk Matrix - Example
7
Use condition and criticality scores as numeric
values to assess risk.
Prioritization Numeric Analysis
8
7
8
11/20/2020
5
Using numerical scores is useful but must remain
in context of how the data was collected.
Condition and criticality scales are estimates.
Multiplying scores can compound the variability
Precision does not equal accuracy.
Some notes on Prioritization
9
Likelihood of Failure – Condition
10
Condition Assessment Scoring Guide
Condition Rating Description
1 New, Very Good Condition: 90 ‐100% remaining service life
2 Good condition, no improvements recommended to maintain function: 60 ‐90%
remaining service life
3 Fair condition, improvements recommended to improve performance or
efficiency: 50% remaining service life
4 Poor condition, improvements recommended to maintain reliability: 20 ‐40%
remaining service life
5 Imminent failure, rehabilitation or replacement required: 0 ‐10% remaining
service life
9
10
11/20/2020
6
Consequence of Failure - Criticality
11
Criticality Scoring Guide
Criticality Component Component Weight Raw Score Scoring Guide
Capacity Affected 30%
1 ≤ 5.0% Capacity Lost
25.1 ‐10.0% Capacity Lost
3 10.1 ‐20.0% Capacity Lost
4 20.1 ‐30.0% Capacity Lost
5 ≥ 30.1% Capacity Lost
Water Quality/System Impact 30%
1 Mild Impact
2Operational Hindrance
4Major Impact
5Mandatory
Redundancy 20%
1Full Backup
2 Partial Backup
4Shared, Not Redundant
5 Dependent
Outage Duration 20%
1 ≤ 1 Days
22 ‐3 Days
43 ‐4. Days
5 ≥ 5 Days
Develop Condition Assessment Scale
Develop Criticality Scale
‒Criteria
‒Weighting Factors
Exercise
12
11
12
11/20/2020
7
Condition Criteria and Scale
13
Likelihood of Failure (Condition)
Weight 1 3 5 7 10
O&M
Protocols 10%
Complete, up‐to‐date,
easily accessible and is
being used. Staff skill
level high
Complete, written, up‐
to‐date, being used
but not easily
accessible. Staff skill
high to intermediate.
Partially developed. Staff
intermediate skill level.
Written but outdated and not
used. Staff skill level junior.
No written protocols.
Staffing entry level.
Performance 20%
Sufficient capacity to
meet average and peak
flow requirements.
Appropriate utilization
and function.
Under‐utilized or
oversized causing
O&M issues.
Sufficient capacity, but does
not meet functional
requirements, or over‐
utilized.
Able to meet current average
capacity demand, but not peak
Unable to meet current
average capacity needs
Physical
Condition 55%
Very good. Indicates the
asset is in like new
condition. Continuation
of the current
maintenance and
operating procedures is
indicated.
Indicates asset is in
good condition. Some
minor additional
maintenance may be
required along with
the current
maintenance and
operating procedures.
Indicates the asset is in fair
condition. These assets have
one or more issues which
require immediate
attention. It is also possible
that the current
maintenance and operating
procedures or intervals may
need to be modified or
adjusted to avoid a
reoccurrence of the
identified issues.
Indicates the asset is in poor
condition. Planning for a major
overhaul or replacement should
begin. Review of current
maintenance practices and
procedures is needed. If this is a
critical asset a predictive
maintenance program should be
evaluated to prevent the asset
from reaching this condition in the
future.
Indicates the asset is in very
poor condition. Failure of
the asset to provide the
desired level of service is
likely. Greater than 50% of
assets will require
replacement. If this is a
critical asset a
comprehensive
maintenance analysis is
recommended to prevent
the asset from reaching this
condition in the future.
Reliability 15%
No corrective work
order events within 12
months
<2 corrective work
order events within 12
months
2‐5 corrective work order
events within 12 months
6‐8 corrective work order events
within 12 months
>8 corrective work order
events within 12 months
Criticality Criteria and Scale
14
Consequence of Failure (Criticality)
LOS Category Weight 1 4 7 10
Service Delivery 20% No impact
Minor impact to process
or out of service less
than 24 hours
Major impact to process,
out of service <24 hours,
or no OEM parts available,
but can be manufactured
Major impact to
process, out of service
>24 hours, outside
services required, or
parts are not available
and cannot be
reproduced
Financial Impact 15% Repair cost <$2,500 Repair cost between
$2,500 and $5,000
Repair cost between
$5,000 and $20,000 Repair cost >$20,000
Safety of Public and Employees 30% No injuries or adverse health effects
No lost‐time injuries or
medical attention
required
Lost‐time injury or medical
attention required
Loss of life or
widespread outbreak of
illness
Public Confidence 10%
No social or economic impact on the
community. No reactive media
coverage. No complaints
Minor disruption (e.g.
traffic, dust noise). No
adverse media
coverage. Some
complaints.
Substantial but short‐term
disruption. Adverse media
coverage due to public
impact. Localized media
coverage.
Long‐term impact. Area
wide disruption.
Regional media
coverage.
Regulatory Compliance 25% No state or local permit violations Possible technical
violation
Probable enforcement
action, but fines or
surcharges unlikely
Enforcement action with
fines or surcharge.
13
14
Lily Pond WTP Asset List
1
Architectural
Water Treatment Plant Building Exterior - Building Envelope
• Roofing and roof drainage system
• Wall system
• Windows frame and glazing
• Doors and Hardware
• Louvers
• Sealants
• Lighting
Water Treatment Plant Building Interiors - Building Finishes
• Floors
• Walls
• Doors and Hardware
• Windows
• Ceilings
• Lighting
Facility/Workplace Safety
Life Safety Compliance - per current building code
Life Safety Plan
Accessibility
Egress signage, warning devices, door hardware
Lighting
Eyewash stations
Electrical
Main Service Gear
Distribution Panels
Transformers
Grounding
MCC
Variable Speed Drives
Starters
Pump Control Panels
General Control Panels
Fuel alarm and inventory
Generator
• Generator Silencer
• Generator Gas Tank
• Generator Battery Chargers
• Automatic Transfer Switch
Lighting
• Exterior Lighting
• Interior Lighting
• Emergency Lighting
Receptacles at code required locations
Disconnects at equipment
Lily Pond WTP Asset List
2
Electrical
Sewage ejector control panel and floats
Overhead motorized door operators
Fire Alarm System
CCTV System
Security System
SCADA/Instrumentation and Controls
System Control Narratives
SCADA
• SCADA Software and version
• SCADA Operator Stations Control Room
• SCADA Development Stations
• SCADA Server
Number of tags used and number of tags available
PLC
• PLC make and model
• PLC software
• PLC number and type of I/O cards
• PLC communication cards
Control panel HMI's makes and models
Historian
Video Server
Network Server
Network switches
Floats
Ultrasonic level sensors
Pressure sensor pipe
Temperature sensors water
Temperature sensors air
Limit switches/sensors/location sensors
Rain gauge
Hydrostatic level sensors
Flow Meters
Analyzers
Chemical pumps
Motorized valves
Solenoid valves
Weir operators
Telemetry cabinets
Modems
Auto dialers
Radio modems
Uninterruptable power supplies
Lily Pond WTP Asset List
3
HVAC
Condensing Units/Rooftop Units
Air Handling Units & Heating/Ventilating Units
Laboratory Fume Hoods/Exhaust Systems
Supply/Exhaust Fans
Unit Heaters
Boilers (2)
Exterior Louvers
General Piping (Hydronic, Refrigerant, Condensate)
Ductwork (Supply, Exhaust, Ventilation)
Control Systems
Plumbing Equipment
Plumbing Fixtures
Fire Protection Equipment (Sprinklers, Flow control valves
Fuel Systems (Tanks, Piping, etc.)
Process Mechanical
Intake structure
• Coarse barscreen
• Sluice gates
• Sump pumps
• Air compressor
Raw water sample pump
Raw water Pumps (3)
Rapid Mix Basins
• Rapid mix baffles
• Rapid Mixers & Motors (2)
• Chain/flight motors and scrapers
• Stop gates
Flocculation tanks
• Flocculator paddle assemblies and shaft
• Flocculator paddle motors
• Stop gates
Sedimentation Basins
• Chain/flight motors and scrapers
• Tube settlers
• Baffles, troughs, and weirs
Filters (3)
• Surface agitators
• Blower (for surface agitators)
• Media (replaced last year)
• Filter Backwash Pumps (2)
• Filter Valve Actuators (Town to provide count or identifiers for the valve actuators)
• Underdrain System (To be reviewed from previous photos taken)
Wastewater Sump Pumps (2)
Wastewater Grinder E-1 Pumps (2)
Lily Pond WTP Asset List
4
Finish Water Pumps (2)
Piping and Appurtenances
• 24" DI raw water intake
• Raw water pump discharge piping and valves
• 12” & 14” DI raw water to pretreatment
• 14” DI to rapid mix basin
• 6” Flocculation basin drain piping
Process Mechanical
Piping and Appurtenances
• 6” and 8” sedimentation basin sludge piping
• 10” and 16” supply filter surface agitator supply piping
• 12” Filter backwash piping
• 16” Filtered water piping to clearwell
• 12" Filter Drain pipe
• 14” Piping to distribution system
Wastewater pumps (2)
16" Wastewater discharge pipe
Chemical Feed Systems
Chlorine (Pre and Post)
• Chlorine storage
• Chlorine piping
• Chlorine pumps (feed water)
• Chlorine rotameters
• Chlorine ejectors
• Chlorine scales
Ferric Chloride
• Ferric chloride pumps
• Ferric chloride tanks
• Ferric chloride piping
Sodium Hydroxide (Pre and Post)
• Sodium hydroxide pumps (4)
• Sodium hydroxide tanks (2)
• Sodium hydroxide piping
Polyaluminum Chloride
• Polyaluminum chloride pumps
• Polyaluminum chloride storage
• Polyaluminum chloride piping
Sodium Permanganate
• 250 gallon bulk tank
• Day tank
• Containment pallet
• Sodium permanganate chemical pumps (2)
• Sodium permanganate piping
Polyacrylamide polymer
• Polyacrylamide polymer pumps
Lily Pond WTP Asset List
5
• Polyacrylamide polymer storage
• Polyacrylamide polymer piping
Ortho/poly-phosphate/Hexametaphosphate
• Ortho/poly-phosphate/hexametaphosphate pumps
• Ortho/poly-phosphate storage
• Ortho/poly-phosphate piping
Process Mechanical
Chemical Feed Systems
Fluoride
• Fluoride Saturator System / feed pumps
• Fluoride piping
Site Civil/Security
Site Access & Security
Drainage
Landscaping
Paving
Mortared Stone Headwalls
Watertight Retaining Wall
Structural
Intake structure
Raw water wet well
Rapid mix basins
Flocculation tank influent channel
Flocculation tanks (2)
Sedimentation basin influent channel
Sedimentation Basins (settling tanks) (2)
Filter influent channel
Filters (3)
Clearwell
Wastewater Sump (300 gallon)
Water Treatment Plant Building
Watertight Retaining Wall
Vehicle Storage and Generator Room
Lagoon Inlet Structure
Lagoon Outlet Structures
Condition Rating Description
1
New, Very Good Condition: 90 - 100% remaining service
life
2
Good condition, no improvements recommended to
maintain function: 60 - 90% remaining service life
3
Fair condition, improvements recommended to improve
performace or efficiency: 50% remaining service life
4
Poor condition, improvements recommended to maintain
reliability: 20 - 40% remaining service life
5
Imminent failure, rehabilitation or replacement required:
0 - 10% remaining service life
Condition Assessment Scoring Guide
Criticality Component Component Weight Raw Score Scoring Guide 0.1 0.2 0.3
1 ≤ 5.0% Capacity Lost Capacity 2.3 2.07 1.656 1.1592
2 5.1 - 10.0% Capacity Lost MDD 1.5 1.5 1.5 1.5
35%ADD 0.5 0.5 0.5 0.5
4 10.1 - 20.0% Capacity Lost
5 ≥ 20.1% Capacity Lost
1 Mild Impact
25%2 Operational Hindrance
4 Major Impact
5 Mandatory
1 Full Backup
25%2 Partial Backup
4 Shared, Not Redundant
5 Dependent
1 ≤ 1 Days 4 hours
15%2 2 - 3 Days
4 3 - 4. Days
5 ≥ 5 Days >2 days
Workshop Notes
Outage Duration 10%
Criticality Scoring Guide
Capacity Affected 50%
Water Quality/System Impact 25%
Redundancy 15%
Town of Cohasset Lily Pond WTP 20-Year Capital Improvement Plan
A-11 200-121837-20003
APPENDIX C – CONDITION ASSESSMENT FORMS
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
1 2 3 4 5
New, Very Good
Condition: 90 - 100%
remaining service life
Good condition, no
improvements
recommended to maintain
function: 60 - 90%
remaining service life
Fair condition,
improvements
recommended to improve
performace or efficiency:
50% remaining service life
Poor condition,
improvements
recommended to maintain
reliability: 20 - 40%
remaining service life
Imminent failure,
rehabilitation or
replacement required: 0 -
10% remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
Condition
Intake Structure Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Coarse Bar Rack (left facing lake) 1 2 1 2 1 4
Coarse Bar Rack (right facing lake) 2 2 1 2 1 4
Sluice Gate Inlet (left) 1A 2 1 1 1 1
Sluice Gate outlet (left) 1B 2 1 1 1 1
Sluice Gate inlet (right) 2A 2 1 1 1 1
Sluice Gate outlet (right) 2B 3 1 1 1 1
Air Compressor 1 1 1 5 1
Raw Water Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Raw Water Pump 1 RWP1
3 5 5 1 4
Raw Water Pump 2 RWP2
1 5 5 1 4
Raw Water Pump 3 RWP3
5 5 5 1 4
Sample Pump NA NA NA NA NA
Rapid Mix Basin Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Rapid Mix Baffles RMB 5 5 2 1 4
Rapid Mixer 1 RMM1
3 5 4 1 4
Rapid Mixer 2 RMM2
3 5 4 1 4
Flocculation Tanks Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Paddle Assembly and Shaft 1 FLF1
3 5 4 5 5
Paddle Assembly and Shaft 2 FLF2
3 5 4 5 5
Flocculator Paddle Drive 1 FLM1
1 5 4 5 4
Flocculator Paddle Drive 2 FLM2
1 5 4 5 4
Sedimentation Basin Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Chain/Flight 1 SDM1
4 5 5 5 5
Chain/Flight 2 SDM2
4 5 5 5 5
Baffles, Troughs and Weirs 1 SDB1 2 4 2 5 5
Outage Duration
Process/Mechanical Condition Assessment Inspection Form
Andy Woodcock
2/4/21 - 2/5/21
Likelihood of Failure (Condition)
Category
Physical Condition
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Separation of the sedimentation basins is difficult. Requires a fiberglass plate manually inserted. Chain and flight mechanism under tube settlers and could not view. In the summer sludge settles on plates and
has to be hosed off. Settling issues. Annual greasing of chain and flights.
Criticality
Both in good condition. Sump pumps in each intake chamber that could not be viewed Structure 15 to 20 years old.
Two for each chamber for a total of 4. Stems are greased once a year. Chamber number (to the right facing lake) two recently replaced. Blow off system to clean bar screens. Piping wleded stainless steel good
condition. Use system monthly on average. Sluice gate stems in good condition. . Manualy actuated. Newer gate in good condition physically leaking. Raw water sample pump in room is in poor condition no
longer used.
Great condition, tank in good condition.Compressor is used to blow off material that collects on the bar screen. Stainless steel discharge piping in good conidtion Control panel for sump pumps in air compressor
room.
The third pump (far left) is not operated, not routinely excercised. Question as to whether it works. Check valves replaced last year on all three pumps. . Middle pump installed two years ago, other pumps were
rebuilt 12 years ago. VFDs installed 12 years ago. NAOH and Permangante feed point redirected to inlet of raw water line. Do not feel like there is enough mixing. Room for a fourth pump. Need to install cap on
opening to wetwell from abandoned storm drain.
Not used anymore. Manual samples.
Wood planks. Corroded bolts attached to wall. Poor condition. Baffle in tank 1 not observed.
Mixer 2 obseved. Blades in good condition. . Motors and mixers original with plant. Poly aluminum feed drops in mixing basin. Chem feed lines exposed and on floor, safety issue. Conidtion of piping is good.
Shaft connection outside of basin corroded and leaking. Polymer added at chamber after mixxing basins. Drain valve stems replaced within the last two years. Greased annually. Openings to sedimentation
basins seem small. Surface corrosion on shaft and staning on paddles. Observed only basin 2. Baffles in good condition.
Motors and gear box for both units repalced in 2019; may have been some work on chains and paddles in 2012; was slated for work in the old CIP.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Process/Mechanical Condition Assessment Inspection Form
Andy Woodcock
2/4/21 - 2/5/21
Baffles, Troughs and Weirs 2 SDB2 2 4 2 5 5
Tube Settler Basin 1 SDT1 1 5 5 5 5
Tube Settler Basin 2 SDT2 1 5 5 5 5
Filters Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Surface Agitators Cell 1 FILS 1
3 1 2 5 2
Surface Agitators Cell 2 FILS 2
3 1 2 5 2
Surface Agitators Cell 3 FILS 3
3 1 2 5 2
Blower (for surface agitators) FILB
2 1 2 5 2
Filter Media FILM
1 5 4 2 5
Filter Underdrain FILU 3 5 5 2 5
Recently inspected and elements replaced last year with the media replacement
Filter Backwash Pump 1 BWP1
5 5 5 1 4
Filter Backwash Pump 2 BWP2
2 5 5 1 4
Filter Valve Actuators FLA
3 4 4 4 2
Cell 1 launders and weirs FILC 1
3 1 2 2 2
Cell 2 launders and weirs FILC 1
3 1 2 2 2
Cell 3 launders and weirs FILC 1
3 1 2 2 2
Wastewater/Sludge Pump 1 (left facing pump
discharge)
WWP1 4 5 5 1 4
Wastewater/Sludge Pump 2 (right facing punp
dishcarge)
WWP2 4 5 5 1 4
Wastewater Grinder E-1 Pump 1 LSP1
3 1 1 1 2
Wastewater Grinder E-1 Pump 2 LSP2
3 1 1 1 2
Finished Water Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Finished Water Pump 1 FWP 1
3 5 5 1 4
Finished Water Pump 2 FWP2
3 5 5 1 4
Sudge Lagoon Area Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Sludge Recirculation Pump SLP 3 1 2 5 4
Sludge Lagoon 1 (left from gate) SLL1 3 5 2 4 4
Sludge Lagoon 2 (right from gate) SLL2 3 5 2 4 4
Sluice Gates (between lagoons, 3) SLG 4 1 1 5 2
Could not view. Discharge piping (PVC) runs on the ground around lagoon 1
Wood baffles, troughs and weirs all look to be in good condition. Basin 2 was drained.
Tube settlers replaced three years ago. Waste tsludge wo ways. Once a month from bottom and daily from a point mid level in sludge blanket. Pedestal valve in fair condition. Troughs lead to a common channel
to filters
Air scour is not original. Works well no problem with operations. Unable to observe
In good shape. Relatively new motor. About 10 years old. Not regularly maintained. Some rust on the discharge piping. Valve exterior in poor condition significant rust on lever.
Media replaced last year
one pump pulled for maintenance; all original piping and equipment including actuators.
Main actuator on discharge may be 20 years old. Total of 12 actuators. Eight actuators replaced less than five years; backwash drainlines have external rust.
Launders in good shape; natural staining suface corrosion. Old surface wash is not used. They do have air scour. Cells 1 and 3 have a structural crack that is patched. Cell 3 same condition. Air scour line in good
condition. Some corrosion and build up on influent pipe.
Scheduled to be pulled for rehab this year for the first time. Light duty run for maybe a half hour a day. Plant drain pumps, for, sludge, spend backwash and plant drains. Pumps to lagoon.
Not obsereved. Internal plant lift station pumps. Discharge piping in fiar condition.
Third pump jockey pump. Not used any more. Pulled annually and serviced off site. Brand new surge valve on downstream of HSP. Motor number 1 rebuilt 2012 to 2015 timeframe. VFDs repalced aroudn 2016
timeframe.
Recieves sludge from WTP. Settles and supernatant to Lily Pond; concrete lined. Could only observe edges.
Holds geofabric bag
Not used.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Process/Mechanical Condition Assessment Inspection Form
Andy Woodcock
2/4/21 - 2/5/21
Polymer System SLP 2 1 2 5 5
Piping and Appurtenances Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
24" DI Raw Water Intake Line 3 5 5 5 4
Raw Water Pump Discharge Piping and Valves 3 5 5 5 2
6" Rapid Mix and Flocculation Basin Drain Piping 3 1 2 5 5
6" and 8" Sedimentation Basin Sludge Piping 3 5 4 5 5
10" and 16" Supply Filter Surface Agitator
Supply Piping 2 1 2 5 2
12" Filter Backwash Piping 3 5 5 5 4
16" Filtered Water Piping to Clearwell 3 5 5 5 5
12" Filter Drain Pipe 3 1 2 5 5
14" Piping to Distribution System 3 5 5 5 4
16" Wastewater Discharge Pipe 3 5 4 5 4
Grinder Station Discharge Pipe 3 1 4 5 2
Condition
Chlorine Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Chlorine Storage CLS
2 1 4 1 1
Chlorine Piping CLL
2 5 5 5 1
Chlorine Pump 1 CLP1
1 5 5 1 2
Chlorine Pump 2 CLP2
3 5 5 1 2
Chlorine Regulator 1 CLR1
1 5 5 1 2
Chlorine Regulator 2 CLR2
1 5 5 1 2
Chlorine Regulator 3 CLR3
2 5 5 1 2
Chlorine Ejectors CLE
2 5 5 1 2
Chlorine Scales CLSC
2 1 2 1 4
Ferric Chloride Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
not observed.
In good condition.
Under pavement; not observed
Discharge valve not used not sure if it works. Not excercised. Minor surface corrosion. No leaks.
Newer PVC with manual ball valves. Could not observe Drain piping
Could not observe
unkown internal condition. Single access point is heaviliy corroded. At chlorine injection point and sample feed lines. Concern of operators. Video GX 40006
minor external rust on pipe flanges
Notes
Notes
Criticality
150 lbs cylinders; three banks of cylinders,two spare cylinders on hand; empty cylinders stored in sperate room.
PVC and ball valves. good condition
bosoter pumps for finished water cl2 solution. Finished water feed point afeter pumps. One pump new one old; new ambient air sensor.
three units; one for raw; one for finished and one backup that can switch between the two; rotameters recently replaced on the raw and finished regulators. ZUZANNA ADD THREE LINES ONE FOR EACH REGULATOR
backup can support raw or finished. Raw and finished do not support each other.
Some surface corrosion. New in the last five years
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Process/Mechanical Condition Assessment Inspection Form
Andy Woodcock
2/4/21 - 2/5/21
Ferric Chloride Pumps FCP
2 5 4 1 1
Ferric Chloride Transfer Pump FCTP 3 1 2 5 1
Ferric Chloride Tanks FCT
3 1 2 1 1
Ferric Chloride Piping FCL
3 4 4 5 1
Sodium Hydroxide Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Sodium Hydroxide Pumps Tank 1 SHP1
1 5 5 1 1
Sodium Hydroxide Pumps Tank 2 SHP2
1 5 5 1 1
Sodium Hydroxide Transfer Pump SHP3
2 1 4 5 1
Sodium Hydroxide Day Tank 1 SHDT1 1 5 4 1 1
Sodium Hydroxide Day Tank 2 SHDT2
1 5 4 1 1
Sodium Hydroxide Bulk tank SHDT3
2 1 4 5 1
Sodium Hydroxide Piping 2 5 4 5 1
Polyaluminum Chloride Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Polyaluminum Chloride Pump 1 PAP1
2 5 5 1 1
Polyaluminum Chloride Pump 2 PAP2
2 5 5 1 1
Polyaluminum Chloride Pump3 PAP3
2 5 5 1 1
Polyaluminum Chloride Transfer Pump PATP
2 1 4 5 1
Polyaluminum Chloride Bulk Tank PABT
2 1 4 4 1
Polyaluminum Chloride Day Tank PADT
2 4 2 4 1
Polyaluminum Chloride Piping PAL
2 5 4 5 1
Sodium Permanganate Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Sodium Permanganate Pump 1 SPP1
2 5 5 1 1
Sodium Permanganate Pump 2 SPP2
2 5 5 1 1
Sodium Permanganate Day Tank 75 galloons SPDT
3 5 4 5 1
Sodium Permanganate 250 Gallon Bulk Tank SPBT
3 1 4 5 1
Sodium Permanganate Piping SPL
3 5 4 5 1
Polyacrylamide Polymer Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Polyacrylamide Polymer Feed Pumps POP
1 4 4 1 1
Polyacrylamide Polymer Transfer Pump POTP
2 4 4 5 1
Polyacrylamide Polymer Storage POS
2 4 2 5 1
Polyacrylamide Polymer Piping POL
1 4 4 5 1
Bulk tanks (55 gal barrels) on containment pallets. Transfert into 80 gallon day tank manualy. Pallet in poor condition; Recovery tank not on spill pallet.
Two. Should be elevated for easy access. Pipe in fair condition.; Improved comtainment is needed. There is an unused containment area that used to be used for lime. Ferric system upgraded 2012 to 2015
timeframe.
Delivered concentrated then diluted onsite. Filling of tank controlled by level thorugh SCADA system. Five years old.
mostly braided tubing; heavlilty stained
Four pumps one for each day tank; new; also transfer pump in good condition; System installed approx. 2016. Replaced the lime system.
1800 bulk; 2, 200 gal day tanks. Day tanks dedicated to different injeciton points raw and finsihed. Recent work on day tanks; pumps, and safety sheild.
good condition; welded stainless feed line runs over doorway to get to bulk tank
Three total, one for each basin and one as a spare. Good condition. Feed system installed in 2018
6000 gal bulk tank; low clearance from ceiling. There is problem with solids accumulting in the tank. It can get up to 75% full of solids. Routine cleaning is required (annuallly) and they use totes for supply during
cleaning. ; transfer pump from bulk to day tank. Have a spare transfer pump may not be same size. bulk tank no known installation date.
flushing system built in; copper water pipe has some corrosion.
Redundant pump installed. System upgraded in 2021 to 2015 timeframe.
Bulk tank only 300 gallons difficult to get deliveries. Currently transfer manually from totes into the bulk tank.In the process of converting to powder potassium permanangante. Messy containment area but fully
functional. Transfer pump stored in containment area.
Loose pipes, tubes and wiring
Three metering pumps; one for each train plus a spare. Spare is not tied into SCADA system but an upgrade is planned.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Process/Mechanical Condition Assessment Inspection Form
Andy Woodcock
2/4/21 - 2/5/21
Ortho/poly-phosphate/hexametaphosphate
Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Ortho/poly-phosphate/hexametaphosphate
Feed Pumps (2)ORP
2 5 5 1 1
Ortho/poly-phosphate/hexametaphosphate
Transfer Pump
OPT
3 5 4 5 1
Ortho/poly-phosphate/hexametaphosphate
Storage ORS 2 1 2 1 1
Ortho/poly-phosphate/hexametaphosphate
Piping ORL 2 5 4 5 1
Fluoride Chemical Feed System Equipment ID Physical Condition Capacity Affected
Water Quality/System
Impact Redundancy Outage Duration
Flouride Bulk Tank
FLBT
2 1 2 5 1
Fluoride Piping FLL 2 1 2 5 1
Fluoride Pumps (2)FLP 2 1 2 1 1
Two pumps in good condition; mounted high and against the wall.
clogging issues after feed pumps. Back presure valves have been disconnected. Piping and pumps installed last year.
System new in 2010 for corrosion control; Metering pumps are mounted low.
Similar configuration to ferric ssytem; on containment pallets
tubing and pvc;
Manually add dry sodium flouride to tank and add water; once a month in winter, weekly in summer. Empty and maintain saturator once a year. Dry storage is out on porcess floor but is located on contaimet
pallet
Overall piping in good condition feed water pipe is copper.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
1 2 3 4 5
New, Very Good Condition: 90 -
100% remaining service life
Good condition, no improvements
recommended to maintain
function: 60 - 90% remaining
service life
Fair condition, improvements
recommended to improve
performace or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
General Condition
Equipment ID # Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Main Service Gear
CUTLER-HAMMER, 277/480V, 3PH,
4W, 60HZ, 1600 AMPS, SER.NO. 4PF-
787029, UL Listed Switchboard
enclosure No. 676360
2 1 5 4 4
Distribution Panels
EATON Lighting and aux power
distribution panels at various
locations
2 1 2 2 1
Transformers
Utility transformer. 13.8/7.87kV -
480Y/277V, 300 kVA 2 2 2 4 2
Grounding All Machinery and equipment 1 1 1 1 1
MCC
UNITROL MCC panels from CUTLER-
HAMMER 2 1 2 2 2
Variable Speed Drives
Raw Water Pumps
Allen Bradley PowerFlex 525, 11kW
each,
1 1 1 1 1
High LIft Pumps
Schneider, ATV660C11T4N2AAWABNG,
460V, 150HP, 211 A
1 1 1 1 1
Notes
Sodium Permanganate Pumps Penta Drives 2 1 1 1 1
Notes
Starters
Backwash pumps Cutler Hammer Disconnects 2 1 1 1 1
Pump Control Panels
Sump pump control panel, Allen
Bradley MicroLogix 1100 2 2 2 2 1
General Control Panels Relay panels at various locations 3 2 2 4 2
Receptacles at Code Required Locations 2 1 1 1 1
Disconnects at Equipment
Disconnects at Sewer pump GE General duty Safety Switch 4 4 4 4 4
Overhead Motorized Door Operators Storage areas in the out building
2 1 1 1 1
Fire Alarm System
Fire Alarm control panel, Fire-Lite
MS-4 with BOSCH D9068
Communicator
2 2 2 4 2
CCTV System 3 2 2 4 2
Security System 3 2 2 4 2
Generator Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Generator Silencer 2 1 1 4 1
Generator Gas Tank 2 1 1 4 1
Generator Battery Chargers Energenius 1 1 1 1 1
Generator Transfer Switch 4 4 4 4 2
Lighting Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Physical Condition
Electrical Condition Assessment
Inspection Form
Khalid Rahman
3/9/2021
Likelihood of Failure (Condition)
Category
Notes
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Outage Duration
Criticality
Notes: 480V, 3PH Utility power supply to the plant, distributed to various load centers at the MCC in the control room. While the physical condition is not bad in appearance, internal condition could not be verified by opening the covers as the plant was in
operation.
Notes:
Notes: Front access to the transformer is completely blocked by shrubs/plants. Need to keep 12 ft clearance in front and 3 ft on the sides. Back is ok with enough spacing.
Notes: Wiring needs improvement.
Notes: There is about 3 ft clearance from the MCC vertical sections to the operator station
Notes
Notes
Notes: One of the ethernet ports on N-TRON 104TX switch is bad. AB MicroLogix controller is relaFvely new. Other components are in good shape
Notes: VFD Run Relays and Normal solenoid valve relays for High lift pumps in the pump room are very old.
Notes
Notes: Cover of these pumps are corroded. This results in an unsafe condition.
Notes
Notes: System maintenance schedule or test record could not be verified. Wiring arrangement needs improvement.
Notes: Wiring needs improvement. Test record could not be verified. Cameras on lightposts outside and in the premises are functional.
Criticality
Notes
Notes
Notes
Notes: Existing Automatic transfer switch is old, and replacement parts are difficult to obtain. A new switch will improve the availability of the plant in case of a power outage.
Criticality
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Electrical Condition Assessment
Inspection Form
Khalid Rahman
3/9/2021
Exterior Lighting
LED Wallmount on perimeter, parking
lot 2 2 2 4 2
Interior Lighting LED Lights in Machinery spaces 2 2 2 4 2
Emergency Lighting
Upstairs hallway 2 2 2 4 2
Chemical room 2 2 2 4 2
Staircase 2 2 2 4 2
Filter gallery/Downstairs 2 2 2 4 2
Intake room 2 4 4 4 2
Compressor room 5 2 2 4 2
Exit lights 2 2 2 4 2
Pump Motors Various locations 2 2 2 2 2
Pump Motors/Flocculation room tank area 3 2 2 2 2
Natural gas Space Heaters Various locations 3 4 2 4 2
Air Compressor
Atlas Copco GA11, Pmax 131 psi, Qv
55.3 cfm, 15 HP 2 2 2 4 2
PA Speakers Various locations 3 2 2 2 2
HVAC Fan Motors Various locations 3 2 2 2 2
Aerator Fan 3 4 4 4 4
Notes: Tested and found in working condition
Notes: Building perimeter lights look worn, but in working condition.
Notes: Lighting frames are corroded in a number of places inside the building.
Notes: Tested and found in working condition
Notes: Tested and found in working condition
Notes: Tested and found in working condition
Notes:
Notes: Could not be tested. In visual inspection appears to be ok.
Notes: HVAC Condensers and Fan coverings are corroded at different locations including at the rooftop.
Notes: Stainless steel casing for the Fan motor, belt and fan arrangement outside the building opposite the pond. This fan is in bad shape, with rust and dirt settling on the belt and motor cover.
Notes: Tested and found in working condition
Notes: Doesn't work now. Previously when the batteries were replaced, it started blinking continuously, so it's disabled now.
Notes: Tested and found in working condition
Notes: Tags indicate regular maintenance work is being done.
Notes: Motors in this area corroded, need maintenance work.
Notes: Some of the space heaters are in bad shape, fins corroded.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Category 1 2 3 4 5
Physical Condition New, Very Good Condition: 90 -
100% remaining service life
Good condition, no improvements
recommended to maintain
function: 60 - 90% remaining
service life
Fair condition, improvements
recommended to improve
performace or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
General Condition
Equipment ID # Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
System Control Narratives N/A
Number of tags used and number of tags available
CP-2 UPSTAIRS CONTROL ROOM:
SLC 5/05, DI = 48, DO = 48, AI = 56,
AO = 64 3 4 4 4 4
Number of tags used and number of tags available
Downstairs Pump room CONTROL
PANEL: SLC 5/05, DI =64, DO = 32, AI
= 40, AO = 16 3 4 4 4 4
Control panel HMI's makes and models N/A
Historian GE IFIX v5.9 2 4 4 4 4
Video Server N/A
Network Server N/A
Network switches
CISCO ASA 5006 X in the control
room upstairs 2 4 4 4 4
Network switches
Catalyst 2950 in the Fire alarm
control panel room 2 4 4 4 4
Turbidity sensors
1720E Turbidity Meter with HACH
monitor and REAL UVT controls 3 2 2 2 2
Ultrasonic level sensors
AMTEK Drexelbrook sensors tanks
upstairs 2 1 1 1 1
Pressure sensor
FOXBORO Exproof pressure
transmitter in the Filter gallery 2 1 1 1 1
Temperature sensors water
Thermostats for High water lift
pumps, Backwash pumps 3 2 2 2 2
Microprocessor dosing pumps
LMI pumps in the chemical room
upstairs 2 1 1 1 1
Chlorine system
LMI pumps in the chemical room
upstairs 2 1 1 1 1
pH Analyzers
Rosemount model 54e pH sensors
in the pump room 2 1 1 1 1
Polymer feed panel
Building at the treatment pond with
bag 3 2 2 2 2
Rain gauge 2 2 2 2 2
Hydrostatic level sensors
Flow Meters
Siemens FM MAG 5000 Flow meter
in the Filter Gallery 2 1 1 1 1
Flow Meters
KROHNE Optiflux 2010 KC C/D/6 LAS-
2/S Flow meter in the Raw Water
line 3 2 2 2 2
Chemical pumps
Various pumps in the Chemical
room upstairs
Motorized valves
AUMA Actuators AM 01.1, 120V, 1.5
kW, NEMA 4X/6 2 1 1 1 1
Motorized valves
KEYSTONE Actuators in the Filter
gallery and pump room 3 2 2 2 2
Solenoid valves
Weir operators
Auto Dialers
Sentinel Sensaphone in the Control
panel CP-2 in Control room 3 2 2 2 2
Modems
LinkSys 5 port 10/100 in the control
room upstairs 2 1 1 1 1
Uninterruptable power supplies
APC BACK-UPS 650's in the Fire
alarm control panel room 3 2 2 2 2
Uninterruptable power supplies
SMART PRO NET UPS in the Fire
alarm control panel room 3 2 2 2 2
SCADA Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Criticality
SCADA/I&C Condition Assessment
Inspection Form
Khalid Rahman
3/9/2021
Likelihood of Failure (Condition)
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Outage Duration
Notes
Notes: There are Operation and Maintenance manuals available but a specific System Control Narrative document does not exist.
Notes
Notes
Notes: Control panel HMI's not available
Notes: Historian seems to be working with essential Trend curves
Notes: Does not exist
Notes: Currently the SCADA system is connected to an Ethernet modem (Comcast business) which is used for remote login and monitoring
Notes: This seems to be working to connect the PLC controllers to SCADA workstation
Notes:
Notes: Turbidity Meters in the Filter Gallery are in good shape, but one on the Raw water line has an open unsealed cable entry that is susceptible to damage from dust, water etc.
Notes
Notes: These are more than 20 yrs old, need an upgrade
Notes: Thermostats are very old, not sure about temperature accuracy.
Notes:
Notes:
Notes: These are in good shape
Notes
Notes: Performance could not be verified
Notes
Notes
Notes: Paint damage on the cover of meter
Notes
Notes: These are in good shape
Notes
Notes
Notes: From operators feedback, this Sensaphone does not give accurate readings for certain I/O's. Alarm settings need to be verified, or replaced.
Notes
Notes
Notes
Criticality
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
SCADA/I&C Condition Assessment
Inspection Form
Khalid Rahman
3/9/2021
Software and version GE IFIX v5.9 2 1 2 2 2
SCADA Operator Stations Control Room DELL Precision 3630 2 1 1 1 1
SCADA Development Stations DELL Precision 3630 2 1 1 1 1
SCADA Server DELL Precision 3630 2 1 1 1 1
PLC Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Make and model ALLEN BRADLEY SLC500 3 4 4 4 4
Software Ladder logic &/or Structured text N/A 4 4 4 4
Number and type of I/O cards
Upstairs CP-2: DI = 3 cards, DO = 3
cards, AI = 5 cards, AO = 8 cards 2 5 4 4 4
Number and type of I/O cards
Downstairs: DI =4 cards, DO = 2
cards, AI = 5 cards, AO = 2 cards 2 5 4 4 4
Communication cards No separate communication cards
Criticality
Notes: GE IFIX v5.9 is now an old version. The most current and up to date version is already 6.5. Newer instruments from various vendors tend to be compatible to the latest version of SCADA software, so it's necessary to upgrade the SCADA software.
Notes
Notes
Notes: Currently the SCADA system is connected to an Ethernet modem which is used for remote login and monitoring. This does not comply with Critical Infrastructure security rquirements. For remote users to login the connection has to be via an encrypted
VPN tunnel. The Woodard & Curran ITS team has developed two options for remote access that align with industry best practices for securing a controls network.
Notes: These are 20 year old PLC's with very few spare I/O's left much less than typical standard of 20% spares. The WTP has already come up with a Capital improvement plan to upgrade the PLC's.
Notes: This software is very old, response time and cycle time higher compared to new softwares, e.g. RSLogix Studio 5000 v 32.xx.xx etc.
Notes
Notes
Notes
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
1 2 3 4 5
New, Very Good Condition: 90 -
100% remaining service life
Good condition, no
improvements recommended to
maintain function: 60 - 90%
remaining service life
Fair condition, improvements
recommended to improve
performance or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
Condition
Water Treatment Plant Building Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Building Interior N/A 2 5 5 5 5
Building Exterior N/A 3 1 1 5 1
Water-tight Retaining Wall Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Water-tight Retaining Wall N/A 3 1 1 5 1
Intake Structure Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Building Interior N/A 2 1 2 5 2
Building Exterior N/A 2 1 1 5 1
Intake Chambers N/A 2 5 5 5 5
Bar Screens N/A 2 1 2 2 2
Raw Water Well Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Raw Water Well N/A 2 5 5 5 5
Rapid Mix Basins Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Rapid Mix Basin 1 (south)N/A 3 5 2 1 5
Rapid Mix Basin 2 (north)N/A 3 5 2 1 5
Flocculation Tanks Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Flocculation Tank Influent Channel N/A 2 (Assumed) 5 5 5 5
Flocculation Tank 1 (south)N/A 2 5 2 1 5
Flocculation Tank 2 (north)N/A 2 5 2 1 5
Sedimentation Basins Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Sedimentation Basin Influent Channel N/A 2 (Assumed) 5 5 5 5
Sludge Effluent Boxes N/A 3 5 2 1 5
Outage Duration
Structural Condition Assessment Inspection Form
Matt Ulrich
2/4/21 - 2/5/21
Likelihood of Failure (Condition)
Category
Physical Condition
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Notes: This rapid mix basin was observed from the floor level only. The concrete making up the basin was observed to be in good condition at time of assessment. No visible crack or spalls could be identified. The protective paint coating on the inside of the tank was
observed to be bubbling and peeling away from the concrete surface. Multiple bolts for the mixer support structure were observed to be in poor condition due to corrosion. Additionally the baffle structure located with the basin was observed to be in poor condition.
Criticality
Notes:
•Walls: All concrete walls and CMU walls were observed to be in good condition at time of assessment. No cracks were observed in the CMU walls; however some isolated cases of peeling paint was observed on the exterior walls in the tank room. Two crack repairs
were observed in the pump room: one crack was located at the southwest corner of flocculation tank 1, while the second was located at the southwest corner of sedimentation tank 1. It appeared that both cracks had been previously repaired using polyurethane grout.
The crack repair at the sedimentation basin was observed to be dry at time of observations, while the crack repair at the flocculation tank was observed to be damp. Additionally, a small concrete spall was identified at the north side of the man door located within the
storage/garage room.
•Floors: Concrete floor slabs were observed to be in good condition at time of assessment. Supporting concrete beams and columns were also observed to be in good condition. Additionally, aluminum grating over trenches was observed to be in good condition.
Likewise the guard railing around the tanks in the tank room was observed to be in good condition however it was noticed that some guard railing included a toe plate and some did not. Toe plates were specifically observed around the three filters. The monorail
system located within the pump room was also observed. No issues were identified with the monorail beam and hoist.
•Roof framing: The precast double tees making up the roof framing were observed to be in good condition at time of assessment. Supporting concrete beams and columns were also observed to be in good condition. Some staining due to water intrusion was observed
in the tank room; however it is understood that the roof has been recently replaced and that all active leaks should have been addressed as this time.
•Defer to Architectural for additional details
Notes: Overall the building exterior was observed to be in fair-to-good condition at time of assessment. Observations were made from the ground surface only. No cracks were observed in the 4" veneer block; however the veneer mortar joints were observed to be in
poor condition at multiple locations around the building due to deterioration. Previous tuck-pointing repairs could be observed on several wall elevations. Additionally, multiple precast concrete sills located below windows were observed to be in poor condition due to
deterioration. Dark brown staining was observed on the unloading dock slab, as well as a portion of the block veneer, on the west side of the building. It is believed that the discoloration is due to chemicals leaking onto the building and slab during delivery and transfer
of the chemicals. Additionally concrete spalls were identified on multiple concrete steps leading up to the unloading dock. Defer to Architectural for additional details.
Notes: The water-tight retaining wall is believed to be an underground concrete seepage wall located approximately 85 to 90 feet north of the main water treatment building. It is believed that this concrete wall was installed to act as a barrier between the septic
system for the building and the adjacent forest. According to plant maintenance, the septic system is no longer used and the treatment building now utilizes city sewer. The concrete wall is believed to be approximately 100 feet long and protrudes above the ground
approximately 1 to 3 feet. The wall was observed to be in good condition at time of assessment. Sporadic cracks and spalls were identified along the length of the wall. All cracks and spalls were observed to be minor.
Notes: The interior of the intake building appeared to be in good condition at time of assessment. No cracks were identified in the CMU walls. The wood roof framing could be observed within the intake chamber room only. No signs of water infiltration or discoloring
of the wood framing could be identified. Additionally the concrete floor and aluminum coverings all appeared to be in good condition. No visible cracks or spalls were observed in the concrete. Defer to Architectural for additional details.
Notes: The exterior of the intake building appeared to be in good condition at time of assessment. No discontinuities or damages in the siding, roofing, or flashing could be observed. Additionally, the concrete wing walls located at the pond side of the structure
appeared to be in good condition. No visible cracks or spalls were observed in the concrete. Defer to Architectural for additional details.
Notes: The (3) intake chambers were not entered and observations were made from the floor level only. The concrete making up the intake chambers was observed to be in good condition at time of assessment. No visible cracks or spalls could be identified.
Additionally the aluminum access hatches and ladder rungs for the east and west intake chambers appeared to be in good condition.
Notes: The coarse bar screens located at the pond side of the intake structure were observed to be in good condition at time of assessment. No visible corrosion or any other deteriorations could be identified. Per the as-built drawings for the intake structure, the (2)
coarse bar screens are fabricated from aluminum.
Notes: The raw water well contained approximately 12" of water in the bottom at the time of assessment. The concrete making up the well was observed to be in good condition. The concrete divider walls located between the pump suction heads were also observed
to be in good condition. (1) crack was identified in the roof slab near the access opening. The crack appeared to hairline. Additionally, multiple aluminum ladder rungs were observed to be missing near the bottom of the well.
Notes: This rapid mix basin was observed from the floor level only. The concrete making up the basin was observed to be in good condition at time of assessment. No visible crack or spalls could be identified. The protective paint coating on the inside of the tank was
observed to be bubbling and peeling away from the concrete surface. Multiple bolts for the mixer support structure were observed to be in poor condition due to corrosion. Additionally the baffle structure located with the basin was observed to be in poor condition.
Notes: The floor grating was not removed to view inside the channel. The concrete is assumed to be in good condition based on the observations made in the rapid mix basins as well as the flocculation tanks.
Notes: The concrete making up this flocculation tank was observed be in good condition at time of assessment. The concrete pier supporting the mixing equipment was also observed to be in good condition. No visible cracks or spalls were identified with the concrete.
The protective paint coating on the inside of the tank was observed to be bubbling and peeling away from the concrete surface. Additionally, the aluminum baffle wall located within the tank was observed to be in good condition. No issues with the baffle wall were
identified.
Notes: The concrete making up this flocculation tank was observed be in good condition at time of assessment. The concrete pier supporting the mixing equipment was also observed to be in good condition. No visible cracks or spalls were identified with the concrete.
The protective paint coating on the inside of the tank was observed to be bubbling and peeling away from the concrete surface. Additionally, the aluminum baffle wall located within the tank was observed to be in good condition. No issues with the baffle wall were
identified.
Notes: The floor grating was not removed to view inside the channel. The concrete is assumed to be in good condition based on the observations made in the flocculation tanks as well as sedimentation basin 2.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Structural Condition Assessment Inspection Form
Matt Ulrich
2/4/21 - 2/5/21
Sedimentation Basin 1 (south)N/A 2 (Assumed) 5 2 1 5
Sedimentation Basin 2 (north)N/A 2 5 2 1 5
Filters Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Filter Influent Channel N/A 2 5 5 5 5
Filter 1 (west)N/A 2 4 2 1 5
Filter 2 (middle)N/A 2 4 2 1 5
Filter 3 (east)N/A 2 4 2 1 5
Clearwell Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Clearwell N/A 2 5 5 5 5
Wastewater Sump Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Wastewater Sump (300 Gallon)N/A 2 1 2 5 2
Vehicle Storage and Generator Room Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Building Interior N/A 3 1 1 5 1
Building Exterior N/A 3 1 1 5 1
Lagoon Structures Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Lagoon Inlet Structure N/A 2 1 2 5 5
Lagoon Outlet Structures N/A 2 1 2 5 5
Lagoon Bypass Channel N/A 2 1 1 5 2
Lagoon Concrete Lining N/A 3 1 2 1 5
Notes: The clearwell sump area contained approximately 2 feet of water at time of assessment. The concrete making up the clearwell was observed to be in good condition. The concrete divider walls located between the pump suction heads were also observed to be
in good condition. Sporadic cracks were observed throughout the clearwell and were primarily identified in the perimeter walls, roof beams, and roof slab. All cracks appeared to be hairline. No spalls were identified in the clearwell. Additionally, multiple aluminum
ladder rungs were observed to be missing near the bottom of the clearwell sump. Multiple threaded rod anchors attaching the fabric baffle walls to the concrete framing were observed to be compromised due to corrosion.
Notes: The sludge effluent boxes were observed from the floor level only. The concrete making up the boxes was observed to be in good condition at time of assessment. No visible cracks or spalls were identified. The steel wall bracket supporting the motor operator
and floorstand at sedimentation basin 1 was observed to be in poor condition due to corrosion. The anchor bolts mounting the steel wall brackets at both sedimentation basins 1 and 2 were observed to be in poor condition due to corrosion.
Notes: This sedimentation basin was not entered due to proper equipment not being on site and allowing safe access into the basin. It is anticipated that a Contractor will enter the basin a later date to inspect and take photographs.
Notes: The sludge hopper located at the west end of the basin was not entered. The concrete making up this sedimentation basin was observed to be in good condition at time of observations. No visible cracks or spalls were identified. Additionally, the metal framing
supporting the tube settler system was observed to be in good condition. No issues with the support framing was identified.
Notes: The concrete making up the filter influent channel was observed be in good condition at time of assessment. No visible cracks or spalls were identified.
Notes: This filter was filled with water and filter media at time of observations. Observations were made from the floor level only. The concrete that was visible appeared to be in good condition. (1) crack was observed in the east wall of the filter tank, just below the
CMU wall. The crack appeared to have been previously repaired.
Notes: This filter was filled with water and filter media at time of observations. Observations were made from the floor level only. The concrete that was visible appeared to be in good condition. No cracks or spalls were identified.
Notes: This filter was filled with water and filter media at time of observations. Observations were made from the floor level only. The concrete that was visible appeared to be in good condition. (1) crack was observed in the west wall of the filter tank, just below the
CMU wall. The crack appeared to have been previously repaired.
Notes: Visible cracks were observed in the concrete lining around the perimeter of the lagoons. Multiple cracks appeared to have been repaired at some point during the life of the lining. Cracks appeared to have been repaired via routing and sealing with polyurethane
sealant. Some sealant was observed to be deteriorated. New cracks appeared to have formed since repairs were last made.
Notes: The lower sump area contained approximately 1 to 2 feet of water and sediment at time of assessment. The lower sump area was not entered. The concrete making up the wastewater sump appeared to be in good condition. Sporadic cracks were observed at
the bottom face of the roof slab. All cracks in the slab appeared to be hairline. Additionally, a substantial amount of "chemical" build-up was observed at the northwest corner of the sump, just below the top slab. Plant maintenance clarified that lime was originally
discharged into the sump at this location and that the process is no longer used.
Notes:
•Walls: No cracks were observed in the CMU walls. Water staining was observed along the back/west wall of the vehicle storage building. Paint was also observed to be peeling from this wall, especially where water staining was visible. Additionally, efflorescence was
observed on the interior face of the CMU block where paint was peeling away. Similar conditions were also observed at the CMU jambs located between garage doors. In addition to the peeling paint and efflorescence, the mortar joints at the door jamb locations
showed signs of deterioration. The water staining, peeling paint, efflorescence, and deteriorated mortar joints all suggest that moisture is seeping through the CMU block wall.
•Floor: The concrete floor slab was observed to be in good condition at time of assessment. A few minor shrinkage cracks were visible in the slab. No major spalling was identified.
•Roof framing: The roof framing was observed to be in good condition at time of assessment. Corrosion was identified along a joist bearing angle, located at the top of the back/west wall, near the northwest corner of the building. The corrosion in this area suggest that
water is leaking in from the roof level. It should be noted that the interior CMU partition wall separating the original generator room from the garage was removed at some point and the generator room no longer exist.
•Defer to Architectural for additional details
Notes: Overall the building exterior was observed to be in fair condition at time of assessment. Observations were made from the ground surface only. No cracks were observed in the 4" veneer block. Water staining was visible on all wall elevations, suggesting water
leakage from the roof level. Efflorescence was also observed in a majority of the veneer mortar joints along the west and south wall elevations. The efflorescence suggest that water is infiltrating the wall and moisture is getting trapped within cavities. The mortar joints
were observed to be in poor condition at multiple locations around the building due to deterioration. Previous tuck-pointing repairs could be observed on several wall elevations. Additionally, concrete spalling was identified on the foundation wall, at the southwest
corner of the building, near ground level. Defer to Architectural for additional details.
Notes: The lagoon inlet structure was filled with water at time of assessment. The existing grating at the top of the structure was not removed to view inside the chambers. Externally the concrete and grating cover appeared to be in good condition at time of
observations. No visible cracks or spalls were identified.
Notes: The existing grating at the top of the outlet structures was not removed to view inside the chamber. Externally the concrete, grating cover, and guard railing appeared to be in good condition at time of observations. No visible cracks or spalls were identified.
Notes: The lagoon bypass channel was filled with water at time of assessment. The existing grating along the top of the structure was not removed to view inside the channel. The concrete and grating cover appeared to be in good condition at time of observations. No
visible cracks or spalls we identified.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Category 1 2 3 4 5
Physical Condition New, Very Good Condition: 90 -
100% remaining service life
Good condition, no improvements
recommended to maintain
function: 60 - 90% remaining
service life
Fair condition, improvements
recommended to improve
performace or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
WTP Building Exterior Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Roofing and roof drainage system 1 1 1 1 1
Wall system 2 1 1 1 1
Windows frame and glazing 3 1 1 1 1
Doors and Hardware 3 1 1 1 1
Louvers 3 1 1 1 1
Sealants 3 1 1 1 1
Lighting 2 1 1 1 1
WTP Building Interior Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Floors 3 1 1 1 1
Walls 2 1 1 1 1
Doors and Hardware 2 1 1 1 1
Windows 3 1 1 1 1
Ceilings 3 1 1 1 1
Criticality
Architectural Condition Assessment
Inspection Form
Linda D'Isabella
10-Mar-21
Likelihood of Failure (Condition)
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Outage Duration
Windows are crank open, operable windows in fairly good condition. Several windows on the first and second floor are rusted, peeling and have some water infiltration damage. Some windows were replaced or re-sealed. It is suggested
that all of the windows be re-sealed to maintain their thermal integrity. It is not an immediate necessity, but should be considered a short term goal.
The main roof of the Water Treatment Building was completed in 2020. The lower level roof was completed a few years ago. The main roof has a new white EPDM roof with walking pads. There is some minor patching but in good
condition. Installation of the new roof included the removal and replacement of the insulation (2) roof drains and (2) overflow scuppers which were added per code requirements. From the interior, some roof drains show signs of light
corrosion but it is not a major concern. Internal storm drain piping was not replaced but re-connected to the new roof drains. The main roof had a new roof ladder installed per code and safety guardrails on the roof. On the lower roof
there was a leak between the wall of the upper roof and the flashing around the windows. New cooper flashing was added between buildings to remedy the water leakage on the interior of the building. Parapet coping is in fairly good
condition. In addition to interior drains, there are two downspouts on the North elevation. There is a lot of water stains along the building exterior that suggests that the roof does not have sufficient drainage and could be overflowing
along the walls. Overall roofing system is a (1), other areas showing coping failure are noted as a (2).
The 12” CMU split face exterior walls (two wythe) with no air space or insulation are in good condition, although the wall system is not an efficient thermal envelope. This type of wall assembly would not be permitted in Massachusetts
under today’s energy code requirements. There are some random water stains along the exterior which might be due to failure in the coping system. There is a lack of weep holes at the bottom of the exterior wall to remove moisture
within the wall system. Water is running along the exterior wall from the roof scupper, on the North elevation, at the location of a re-directed downspout around a mechanical unit. The scupper should be investigated for possible clogging.
It is overflowing onto the exterior wall. This does not need to be resolved immediately, but moisture can lead to mold growth and health hazards. There are no cracks at the existing control joints. The loading dock bumpers are an integral
part of the buildings function and need to be replaced. The Permanganate fill area has spill damage and is staining the building. Discolorations does not affect the function but is strictly aesthetic.
Windows are single pane construction and should be replaced in the future to a double pane system to improve the building’s thermal efficiency. Some of the windows have been replaced but remained single pane windows. About 10-
20% of the exterior caulking is cracked and broken down. Mostly at the corner conditions. Other occasional issues involve minor rust development, peeling paint and random exterior stone sill damage. These conditions should be
corrected in the future and do not affect the overall building function. Future replacements should be thermally broken frames with insulated double pane glazing with an inert gas to improve the energy performance of the building.
Exterior door on the East elevation, located on the second floor out of the interior corridor, is missing a rain hood. During heavy rains, water is running down the exterior wall and into the interior of the building through a crack in the
weatherstripping. It was mentioned by the client that the water entering the building runs down the corridor stairs. A rain hood, or perhaps a 3 ft. x 4 ft. canopy, would help divert the excess water from entering the building. This should
be addressed as a short term goal. Second floor overhead rolling door on the West elevation, is not original. It was replaced from two initial double doors, but the original rusted frame was not removed. The overhead door does not have
weatherstripping, and currently allows rodents to enter the building underneath the door. Effective weatherstripping should be evaluated at all door types. Installed hardware functioning does not meet current code requirements but
there is not an immediate need to replace the hardware. Recommend as hardware fails, replacement should meet ADA compliance.
Exterior radiator and mechanical louvers show signs of damage, including peeling paint and discoloration. However, they are functioning and don’t need immediate replacement. On the South elevation, an original intake louver was
replaced with a plywood infill and minimized louver opening. This should be replaced to provide the adequate ventilation that was originally designed for the building.
Exterior sealants are in fair condition. Control joints are functioning properly. The status of the exterior window sealants is inconsistent. Most of the windows are original and the sealant is starting to break down in some areas. It is
recommended that the windows be evaluated in the short term for improved performance.
Small light at entry does not provide adequate illumination for the space. Minimal exterior lighting. Not immediately necessary, but additional lighting should provide exterior illumination of the doors and accessways.
Criticality
Main entrance hallways, control room and hallways of the second floor, have 9”x 9” VCT tile that most likely contain asbestos components. It is suggested that a Hazardous Materials study be completed to understand the level of hazard.
Replacement is not necessary as long as the tile remains undisturbed. Tile in the Record Storage Room on the second floor is scraped and should receive new flooring in the short term. Carpeting in the offices and main rooms of the first
floor are stained but not in need of replacement. New carpet or flooring would be for aesthetic reasons only. The concrete floor treatment of most of the processing areas are in good condition. The Treatment Process Area on the second
floor has a concrete coating that is peeling and completely removed in some locations. It should be re-coated to increase the protection of the floor from chemicals and other elements. Stairs, ramps and railings on the interior of the
building are in good condition.
The CMU interior walls on the first and second floor are generally in good condition. Thermostat control issues and high temperatures in the second floor Chlorination and Treatment Process Area have made several painted CMU walls
begin to peel. This is especially true on the exterior walls where moisture has developed between the exterior and interior walls. This condition is aesthetic and does not affect the function of the space. Minor holes in the walls of the
Treatment Process Area could be patched and are probably due to the relocation of mounted equipment. In terms of interior furniture and equipment, the Break Room on the first floor has a kitchen with a range hood that is not compliant
with the current building code. The Lab on the second floor has countertops and cabinets the are in working condition and do not need to be replaced. The countertops are particularly durable and look good, except for the around the
sinks. The seams of the counter at the sink areas are breaking down. The counter and sinks look damaged on the surface. It is not a necessity that it should be replaced, but should be considered in the near future. The cabinets have some
minor corrosion, but could be resurfaced with new hardware to improve the overall image. Cabinet areas function normally without a need for improvement. There is some corrosion under the secondary sink that should be addressed.
The exhaust fan fume hood is new and the glass piping under the sinks are in good condition. When the cabinet systems start to fail, replacements should be installed that are ADA compliant.
The Chlorine room is only accessible from the exterior and has one door. The door is a regular doorknob and will be upgraded to panic hardware in a few weeks. The office on the first floor has rust on the door frame and not in need of
immediate repair. Installed hardware functioning does not meet current code requirements but there is not an immediate need to replace the hardware. Recommend as hardware fails, replacement should meet ADA compliance.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Architectural Condition Assessment
Inspection Form
Linda D'Isabella
10-Mar-21
Lighting 1 1 1 1 1
Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Interior 1 1 1 1 1
Condition
Exterior 2 1 1 1 1
Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Interior 1 1 1 1 1
Condition
Exterior 1 1 1 1 1
•Walls – Wood siding has slight cracking damage, but overall in good condiHon. No water damage. Wood siding does require future maintenance.
•Roofing and Drainage System – CDownspouts discharge to underground storm water piping. The client menHoned the roof is new and well documented.
•Window Frames and Glazing – No repairs needed to the windows, frames or sealant installaHon.
•Door and Hardware - Door hardware is upgraded, including lever handles. No issues that need to be resolved at this Hme. The funcHon of this building does not require handicap accessibility.
•Louvers - The louvers are fairly new and do not show deterioraHon.
•Sealants – Sealants for the windows and louvers are not showing any signs of failure and water damage.
•LighHng – Exterior lighHng is adequate. It is suggested to add lighHng on the North and East elevaHons not facing the pond.
There are noticeable water damage stains in the acoustical ceiling tiles on the first and second floors. Process rooms have exposed concrete T beam ceilings. Most of the exposed structure ceilings are in good condition. However, the
Treatment Process Area on the second floor has discoloration between the seam of the concrete T-beams that extends the full length, down the center, of the space. In one location, there was an attempt to patch the damage. The client
mentioned that the main roof of the Water Treatment building was replaced in 2020 and the lower portion a few years ago. There are a few internal drains and the storm piping runs through the hallways. The ceiling stains are caused by a
leak in the storm water system. The damage to the ceilings in the building could have been resolved with the new roof installation. It should be investigated if the ceiling damage is recent and continual. This should be remedied in the near
future. Undesirable water infiltration could cause mold and other environmental and health concerns. Minor holes in the exposed ceiling of the Treatment Process Area could be patched and are probably due to the relocation of mounted
equipment. The Record Storage Room on the second floor has dripping of tar along the wall. This was caused by the modified bitumen roofing or tar and gravel roof. During a hot day, the tar slid through a fissure between the double T-
beam construction and dripped along the interior wall. It is not an issue of concern with the new roof, but can be aesthetically cleaned. During the virtual walk-through, it was noted that the Pump Room on the first floor did not have a fire
damper at the duct penetration and should be evaluated.
The lighting throughout the interior of the Water Treatment Plant facility is in good condition. Based on observation, the lighting is functioning properly and efficiently. No recourse is required.
VEHICLE STORAGE & GENERATOR ROOM
Criticality
•Floors - Concrete floor shows removal of the protecHve coaHng in random areas. It should be considered that the floor be re-sealed, but it does not affect the funcHon of the building.
•Walls - The CMU walls have some light peeling but not a major concern. Temperature controls should be invesHgated. There are two ceiling mounted space heaters. It was menHoned by the client that venHlaHon in the building is limited.
•Doors and Hardware - There is one door into the generator room that has panic hardware as required by code. There is also one door into the garage. Recommend as hardware fails, replacement should meet ADA compliance.
•Ceiling - Exposed ceiling joists and metal roof show some minor paint peeling caused from heat, moisture or a combinaHon of both.
•LighHng - LighHng throughout the interior of the building is untarnished and efficient.
Criticality
•Walls - The exterior of the building is 12” split face CMU block. There is efflorescence showing on the exterior meaning moisture is present in the wall system. There is also signs of water stains on each elevaHon the begins at the top of the
roof and continues along the elevation to ground level. The roof coping should be evaluated for intermittent cracks allowing water to access the exterior of the building.
•Roofing and Drainage System - Water is not diverted by guNers, downspouts or scuppers. There are internal drains and storm water piping only. It seems that during heavy rains, the internal drains are ineffecHve and the excess water is
going through a failed opening in parapet coping and along the side of the exterior walls. The client noted that the garage roof was replaced 5 years ago.
•Window Frames and Glazing - There are no windows or glazing condiHons in the building.
•Door and Hardware - Door hardware was discussed under the “Interior” porHon of this evaluaHon. The weatherproofing of the overhead doors should be checked, similar to the main building.
•Louvers - The louvers on the exterior show slight wear and tear and visible signs of water dripping onto the exterior from the lower porHon of the louvers. The most water damage to the walls and louvers are located on the west elevaHon.
•Sealants – Sealants around the doors and louvers are in fair condiHon and should be evaluated for efficiency.
•LighHng - Exterior lighHng is minimal. The East elevaHon, with the overhead doors, do not have any exterior lighHng, including the south elevaHon. There are more lighHng fixtures on the west elevaHon and only one on the north side, but
it is not located at the exterior door for egress visibility. Additional lighting should be considered in the short term.
WATER INTAKE BUILDING
Criticality
•Floors – The Raw Water Intake building was more recently constructed. The concrete floors are in good condiHon.
•Walls – The CMU walls do not need repair or resurfacing.
•Doors and Hardware – Door hardware is upgraded, including lever handles. No issues that need to be resolved at this Hme. The funcHon of this building does not require handicap accessibility.
•Window Frames and Glazing – The windows and window sealant are funcHoning properly.
•Ceiling – Exposed wood ceiling structure is in good condiHon. Wood construcHon can show future effects of heat, moisture or a combinaHon of both.
•LighHng – The amount of arHficial light is minimal and could be increased.
Criticality
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Category 1 2 3 4 5
Physical Condition New, Very Good Condition: 90 -
100% remaining service life
Good condition, no improvements
recommended to maintain
function: 60 - 90% remaining
service life
Fair condition, improvements
recommended to improve
performace or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Life Safety Compliance - per current building code 3 1 1 1 1
Life Safety Plan 3 1 1 1 1
Accessibility 5 1 1 1 1
Egress Signage, warning devices, door hardware 2 1 1 1 1
Lighting 1 1 1 1 1
Eyewash Stations 5 1 1 1 1
Category
Facility & Safety Condition
Assessment Inspection Form
Linda D'Isabella
10-Mar-21
Likelihood of Failure (Condition)
Consequence of Failure (Criticality)
Per OSHA life safety code regulations, there should be an eyewash station for immediate emergency use within the work area for quick flushing of eyes where a person’s eyes may be exposed to corrosive materials. On the first floor, the
Pump Room, had expired potable water bottles for the eyewash station. This should be upgraded in the short term to meet the code requirements. On the second floor, the Laboratory Room and Chlorine rooms did not have eye wash
stations. The Chemical Feed Area did have an eyewash station that looked up-to-date per standards. The client mentioned it was installed in 2015. Overall, chemical rooms should be investigated to check for eyewash station locations and
availability.
Capacity Affected
Water Quality/System Impact
Redundancy
Outage Duration
Criticality
Current building code for Cohasset, MA is the 2015 IBC. The Water Treatment Plant is approximately 15,100 sf. The Water Treatment building does not have a fire suppression system. Fire extinguishers were visibly noticed at the main
entrance, office and pump room areas of the first floor, as well as the Chemical Room and Chlorine Rooms on the second floor. Other process areas should provide a fire extinguisher. Based on code, there should be a fire extinguisher at
each egress door of the facility. The maximum distance of travel to a fire extinguisher is 75 ft. The first floor and second floor travel distance from each egress exit is approximately 86 ft. and should have an additional fire extinguisher
between the exits. Per NFPA 101, the means of egress must be located no less than half of the diagonal distance of the area being served. The Water Treatment facility meets this criteria. In the Treatment Process Area on the second floor,
the stainless steel safety railings for the process tanks are in good condition. Per the IBC code, the exit access travel distance for non-sprinklered, Factory occupancy is 300 ft. The Water Treatment Facility meets this requirement. The
exterior second floor entrance into the building on the East elevation has an unleveled asphalt walkway and broken handrail that needs to be addressed.
The main concerns that should be evaluated for life safety include adequate eyewash stations in chemical room locations, additional fire extinguisher access, as well as emergency alarm and lighting conditions on each floor. The asphalt
grade level should be leveled for safety on the second floor at the entry on the East elevation. The handrail at this location is broken and should be repaired for stability.
According to ANSI (American National Standards Institute) and the ADA (American disabilities Act) guidelines there are some concerns with accessible route/entrance, parking and signage. The main entrance to the building has a step to
the entranceway and does not provide handicap access. A ramp would need to be provided. Within the vestibule the length of the space would have to be extended to 7 feet to accommodate the length of a wheelchair and the length of
an inward door swing. The main egress doors are equipped with a closer and panic hardware. Door threshold should maintain a ¼” height. Exterior grading to the entry needs to be evaluated. A handicap parking space is provided and
marked with a handicap sign, but the ground is not properly designated as a handicap space according to code. In addition, if the parking lot accommodates 26-50 spaces, two handicap spaces should be provided. The number increases for
every 25 spaces. On the interior of the building at the entry, the office transaction window does not have a portion at the ADA maximum required height of 34 inches. Handicap access is not a requirement in the other spaces of the
building, other than the main entrance, offices, conference room and restrooms. The Men’s and Women’s restrooms are not handicap accessible. The rooms would need to be reconfigured to accommodate wheelchair access and
maneuverability. If the facility undergoes a major renovation, the non-compliant ADA issues will need to be addressed.
For the egress signage, there are lighted exit signs provided at the egress doors. Braille exit signs, were not included in the egress signage per ADA. The first floor hallway had emergency exit lighting but an alarm system was not visible.
There was an old alarm bell. The Pump Room has an emergency pull alarm. There should be an emergency alarm system at each floor. For the door hardware, egress doors did have closers as required and panic devices per accessibility
and hardware standards. The Chlorine room is only accessible from the exterior and has one door. The door is a regular doorknob and will be upgraded to panic hardware in a few weeks. Recommend as hardware fails, replacement should
meet ADA compliance.
Lighting throughout the Water Treatment Plant provided adequate lighting along the path of egress on the first and second floors. No upgrades are necessary at this time.
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
1 2 3 4 5
New, Very Good Condition: 90 -
100% remaining service life
Good condition, no
improvements recommended to
maintain function: 60 - 90%
remaining service life
Fair condition, improvements
recommended to improve
performace or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
Condition
Water Treatment Plant Building Equipment ID Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Air Handling Units (Lab/Office Second Floor) PSWT-AHUFC-1,2 5 1 1 1 1
Hydronic Boilers PSWT-BLR-1,2 3 1 1 1 1
Cabinet Hydronic Heaters PSWT-CUH-1,2,3 5 1 1 1 1
Condensing Units (Lab/Office Second Floor) PSWT-CUR-1,2 4 1 1 1 1
Split System Dehumidifier PSWT-DHR-1,2 5 1 1 1 1
Exhaust Fans (Visible)PSWT-EF-6,7,8,9,10 4 1 1 1 1
Exhaust Fans (Concealed)PSWT-EF-1,2,3,4,5 4 1 1 1 1
Hydronic Expansion Tank PSWT-ET-1
3 1 1 1 1
Hydronic Pumps (Circulators) PSWT-HWP-1,2
3 1 1 1 1
Hydronic Unit Heaters PSWT-UH-1,2 (6 TOTAL)5 1 1 1 1
Physical Condition
HVAC Condition Assessment Inspection Form
Michael Sutherland
3/9/2021
Likelihood of Failure (Condition)
Category
Notes: Units were repalced in 2007-2008 tiimeframe however likely approaching end of serving life in the next 2-4 years. Direct Expansion Models with ventilation air and hydronic heating coils. Refrigerant type unknown but likely outdated and in need of upgrade.
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Outage Duration
Criticality
Notes: Unit is original (1974) Direct Expansion Models with ventilation air and hydronic heating coils. Refrigerant type unknown but likely outdated and in need of upgrade. Poor airflow distribution to zone and doesn't meet latest requirements. Total Quantity of Units
= 6. System is operational however is nearing the end of its service life.
Notes: Boilers were observed to be in fair conditoin and appeared to be operational. No visible dates were listed on the equipment service tags.
Notes: From observation units appear to be original. Cabinet Hydronic Heatesr have a median service life of 20 years pushing these units past the usable life.
Notes: From observation the dehumidifer inside the pump room and the roof mounted condensing unit are showing signs of wear and beyond the service life of the equipment.
Notes: Some fans were original while some had been replaced. In general due to age of facility all will likely past their useful life or nearing the end of useful life.
Notes Some fans were original while some had been replaced. In general due to age of facility all will likely past their useful life or nearing the end of useful life.
Notes: The expansion tank was in fair condition however due to the age of the equipment the equipment is likely nearing the end of its service life and should be replaced when the hydronic system is replaced.
Notes: The hydronic pumps were observed to be in fair to poor condition and had markings that they had been recently rebuilt. The pumps likely have some service life left, however will need replacement within the next few years. Recommend replacing pumps when
the boiler plant is revised.
Notes: From observation the unit heaters appear to all be original construction. however the median service life of 20 years is surpassed
Facility Name Lily Pond WTP Inspected By
Location WTP Building Date
Category 1 2 3 4 5
Physical Condition New, Very Good Condition: 90 -
100% remaining service life
Good condition, no improvements
recommended to maintain
function: 60 - 90% remaining
service life
Fair condition, improvements
recommended to improve
performace or efficiency: 50%
remaining service life
Poor condition, improvements
recommended to maintain
reliability: 20 - 40% remaining
service life
Imminent failure, rehabilitation or
replacement required: 0 - 10%
remaining service life
1 2 4 5
≤ 5.0% Capacity Lost 5.1 - 10.0% Capacity Lost 10.1 - 20.0% Capacity Lost ≥ 20.1% Capacity Lost
Mild Impact Operational Hindrance Major Impact Mandatory
Full Backup Partial Backup Shared, Not Redundant Dependent
≤ 1 Days 2 - 3 Days 3 - 4 Days ≥ 5 Days
WATER TREATMENT PLANT BUILDING
WTP Building Exterior Condition
Physical Condition Capacity Affected Water Quality/System Impact Redundancy Outage Duration
Access 2 1 1 1 1
Security 5 1 1 1 1
Drainage 3 1 1 1 1
Landscaping 3 1 1 1 1
Mortared Stone Headwalls 2 1 1 1 1
Building Accessibility (ADA)5 1 1 1 1
Watertight Retaining Wall
Criticality
Civil Condition Assessment
Inspection Form
James Warner
3/9/2021
Likelihood of Failure (Condition)
Consequence of Failure (Criticality)
Category
Capacity Affected
Water Quality/System Impact
Redundancy
Outage Duration
The building Access into the facility will not meet the curent ADA requiements for building access and parking reqirements. One parking space is required, but needs to meet the local and ADA striping and slope criteria.
No reasonable site security exists. One manually gate (with card reader stand that was unknow by the operators to it use exists) was noted, but based on information provided and site visit evidence, the site is open to the public for
parking and dog walking.
Site Minor erosion occurs in area where the pavement discharges to the lake and some minor erosion was noted near the inlets. Vegetation and trees have not been maintained at the outfall, in one case a 6” tree blocks the 12” outfall
pipe.
Normal landscape maintenance with some fortification of the discharge location is recommended to be complete with the normal maintenance of the landscape and site work.
Acceptable condtion, wall is functioning with no anticipated failure.
The building Access into the facility will not meet the curent ADA requiements for building access and parking reqirements. One parking space is required,