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HomeMy WebLinkAboutWater Quality Report 2007 (PDF)JULY 1, 2007 WATER QUALITY REPORT The Cohasset Water Department (DEP ID# 3065000), under the direction of the elected Board of Water Commissioners, provides public drinking water to about 2,400 connec- tions for about 7,100 Cohasset residents and provides and maintains a water system for fire fighting. We provide drinking water for almost 90% of the population of Cohasset. This Water Quality Report describes the sources of our drinking water and the quality of that water for the period from January 1 – Dec. 31, 2006. During 2006 we met or exceeded all applicable standards for drinking water quality. 2006 WATER SYSTEm ImPROvEmEnTS In 2006 the Water Department: u Completed the design phase and awarded the contract to construct 19 Rain Gardens in the Lily Pond Watershed in 2007 to reduce nutrient loading and pollutants entering Lily Pond. u Replaced 6,300 feet (1.2 miles) of undersized water mains to improve water service & fire protection. u Acquired 32 acres of land in the watershed of Lily Pond and the Aaron River Reservoir. u Made numerous improvements & upgrades to the Lily Pond Treatment Plant to preserve the quality of our drinking water.2007 Water Quality ReportPhotos from top to bottom: Lily Pond at the Water Treatment Plant on King Street, Bound Brook at Beechwood Street, Aaron River Reservoir and Rain Garden at the Water Treatment Plant 339 King Street Cohasset MA 02025 781-383-0057 www.cohassetwater.org COHASSET BOARD OF WATER COMMISSIONERS Glenn A. Pratt, Chairman Nathaniel Palmer, Vice-Chairman John K. McNabb, Jr., Clerk Town of Cohasset & Norfolk Ram Group LLC Cohasset is a South Shore community with a population of 7,261. Approximately 90 percent of the drinking water supply comes from the Lily Pond surface water treatment plant. Lily Pond is a shallow 51 acre pond with a watershed of 1,603 acres. The pond is eutrophic. Flow to Lily Pond is supplied by Peppermint Brook and Brass Kettle Brook The reduction of nutrient loads and control of in-lake vegetation were identified as goals in the development of pond and water supply management strategy. Low Impact Development Techniques were instituted to treat roadway runoff prior to discharge to the pond. The BMPs selected include Bioretention Cells (Raingardens) and vegetated bioretention swales. A demonstration Raingarden was constructed as an educational tool for the community. Five Raingardens and two vegetated bioretention swales were constructed in the road right-of- way. Twenty-six additional raingardens will be constructed. The runoff filters through specially engineered soil. This natural process reduces pollutant and nutrient levels, reduces elevated tempera- tures of stormwater during summer months, and attenuates peak flows. The treated stormwater is collected by under- drains and returned to the stormwater sys- tem or infiltrated back into the ground. For further information contact: Michael F. Clark, P.E. Norfolk Ram Group LLC mclark@norfolkram.com (5080 747-7900 x 193 C OMMONWEALTH OF M ASSACHUSETTS 2006 S MART G ROWTH AWARD WInnInG RAIn GARDEn PROJECT In 2006 the Cohasset Water Department and it’s engineers, Norfolk Ram, were the recipients of the Commonwealth of Massachusetts Smart Growth Award for the Rain Garden Project. Rain Gardens are MA DEP approved stormwater Best Management Prac- tices (BMP) that use natural filtration processes to treat stormwater runoff; vegetation and soils remove pollutants such as nutrients, suspended solids, salt, and petroleum by-products. LID enables developed areas to work hydrologically like natural, undeveloped land and allow stormwater treatment to be micro-managed at its source. (More about Rain Gardens Inside) Cohasset Water Department 339 King Street Cohasset MA 02025 PRESORTEDSTANDARDUS POSTAGEPAIDPERMIT NO. 47COHASSET, MA POSTAL PATRONCOHASSET, MA 02025 This report is printed on 100% recycled paper using soy-based inks, all prepress is digital (no chemicals are used) Printer: Millennium Graphics Design & Production: Advertising by design www.karenquigley.net In This Issue 2007 Water Quality Report 2006 Water System Improvements The Rain Garden Project New Facilities Community Involvement Inside Panel 2006 Water Quality Results What the Water Department is Doing to Protect Your Water Supply & What You Can Do Where Your Drinking Water Comes From Health Effects Information Contaminants in Drinking Water Vulnerable Populations Warning Watershed Map SWAP Report on Cohasset Definitions nEW PUmPInG FACILITIES 2006 saw the construction of two new pumping facilities: the Ellms Meadow Wellfield Pumphouse and the Whitney Crossing Pump Station on Route 3A. The Ellms Meadow facility will allow the introduction of wellwater into the distribution system improving the quality of our drinking water. The new facility on Route 3A serves the Linden Woods development in Hingham. COnTACT US Please call Brenda Douglas at the Water Department with any questions or concerns. 781-383-0057 (fax 781-383-2906) For more information about the Water Department visit our website: www.cohassetwater.org This report is available at the Water Department, Town Hall, and the Paul Pratt Memorial Library, and on our website: www.cohassetwater.org COmmUnITY InvOLvEmEnT We encourage public interest and participation in decisions affecting Cohasset’s drinking water. The Water Commission usually meets every other week at 6:00 pm at the Lily Pond Water Treatment Plant, 339 King Street. Meeting notices are posted at Town Hall. Feel free to attend and to participate. www.cohassetwater.org 3 feet of a typical bioretention soil mix achieves the following pollutant removal*: copper 93% lead 99% phosphorus 81%, total nitrogen 43% nitrates 23% *Experimentation by Dr. Allen Davis, University of Maryland and reported in Low-Impact Development Design Strategies, Prince George's County, Maryland Department of Environmental Resources Photos from top to bottom show: Partial excavation, Peastone placement, Soil mixing, Initial planting, Outfall pipe, The Rain Garden in spring 2007 Photos from left to right: Rain Gardens protecting Peppermint Brook – Pond Street at the Middle/High School, Arrowwood Street & Evergreen Street HOW RAIn GARDEnS WORK Stormwater runoff is directed into a rain garden, where it is prefiltered through a hardwood mulch layer prior to infiltrating through the bioretention mix (comprised of shredded hardwood, coarse sand, and topsoil). The bioretention soil mix removes mineral sediments and contaminants such as nitrogen and phosphorus, which are damaging to the watershed. After the stormwater has filtered through the bioretention soil, it passes through a peastone under-drain layer, and is directed into a perforated PVC drainage pipe connected to the existing stormwater drainage system. In addition to being reduced in volume, the treated runoff contains significantly lower levels of nutrients and contaminants, and results in improved water quality at Lily Pond. In the spring of 2005, the Water Department constructed a prototype Rain Garden in the parking lot of the Water Treatment Plant on King Street. (See photos on left) Benefits of the Rain Garden Project u Maintenance and restoration of the natural hydrology of the Lily Pond watershed u Reduced transport of sediments and other pollutants to our drinking water u Protect and preserve the Lily Pond / Aaron River Reservoir watershed u Reduced costs for maintaining stormwater collection and treatment facilities u Increased property values and improved neighborhood aesthetics through landscaping of drainage sites u Improved water quality u Improved fish & wildlife habitat Lily Pond (the source of 90% of Cohasset's drinking water) receives a nutrient load from its watershed in excess of the standard for optimal water quality. To improve water quality and preserve the integrity of our drinking water supply this nutrient loading must be reduced. To this end, the Cohasset Water Department has begun a project utilizing low impact development (LID) best management practices (BMP): the Rain Garden Project. This project will retrofit existing surface water collection systems improving the hydrology and reduc- ing contaminant strain on Lily Pond and the Aaron River Reservoir. Reduced pollutant loadings will enhance the performance of the Water Treatment Plant, reduce operating costs, and improve water quality, taste and odor. The goal is to reduce nitrogen loading by 658 kg/yr and the phosphorus loading by 22 kg/yr. A pre-construction/post-construction sampling program is in place to measure the project's effectiveness. In total, approximately 45 rain gardens will be constructed in the Lily Pond watershed. Funding The Cohasset Rain Garden Project is financed in part by a Section 319 Water Quality Grant from EPA (administered by the MA DEP). Project Status Phase 1: construction is complete on 6 rain gardens Phase 2: construction of 15 additional rain gardens will occur in the Spring/ Summer of 2007 Phase 3: design plans for 25 more rain gardens will go out to bid late 2007 Community Education & Outreach The Cohasset Water Department will host educational meetings for residents; and future newsletters will address additional water quality pro- tection including measures that can be implemented by homeowners. The Water Department will provide all maintenance to the rain gardens at no cost to homeowners or the Town of Cohasset. Plants were chosen for suitability with Cohasset's soil and climate by the Cohasset Community Garden Club. D C B A High priority neighborhoods include: A Veteran’s Project on Bear Hill overlooking Peppermint Brook B King Street abutting Lily Pond C Beechwood Street by Bound Brook D Aaron River Road abutting the Aaron River Reservoir Rain Gardens and grass swales will be installed in neighborhoods abutting tributar- ies to the Lily Pond drinking water supply. COHASSET'S RAIn GARDEn PROJECT: nature’s way to filter stormwater runoff & safely protect our drinking water THE WATER COmmISSIOn’S RAIn GARDEn PROJECT Town of Cohasset & Norfolk Ram Group LLC Cohasset is a South Shore community with a population of 7,261. Approximately 90 percent of the drinking water supply comes from the Lily Pond surface water treatment plant. Lily Pond is a shallow 51 acre pond with a watershed of 1,603 acres. The pond is eutrophic. Flow to Lily Pond is supplied by Peppermint Brook and Brass Kettle Brook The reduction of nutrient loads and control of in-lake vegetation were identified as goals in the development of pond and water supply management strategy. Low Impact Development Techniques were instituted to treat roadway runoff prior to discharge to the pond. The BMPs selected include Bioretention Cells (Raingardens) and vegetated bioretention swales. A demonstration Raingarden was constructed as an educational tool for the community. Five Raingardens and two vegetated bioretention swales were constructed in the road right-of- way. Twenty-six additional raingardens will be constructed. The runoff filters through specially engineered soil. This natural process reduces pollutant and nutrient levels, reduces elevated tempera- tures of stormwater during summer months, and attenuates peak flows. The treated stormwater is collected by under- drains and returned to the stormwater sys- tem or infiltrated back into the ground. For further information contact: Michael F. Clark, P.E. Norfolk Ram Group LLC mclark@norfolkram.com (5080 747-7900 x 193 C OMMONWEALTH OF M ASSACHUSETTS 2006 S MART G ROWTH www.cohassetwater.org lIly POnd & aaROn RIvER RESERvOIR watERShEd Lily Pond has a maximum capacity of about 100 million gallons of water and is 52 acres in size. The 136 acre Aaron River Reservoir, which can hold a maximum of 550 million gallons of water, is used to supplement Lily Pond in times of high water demand. The watershed for Lily Pond and the Reservoir covers an area of 5,892 acres, 9.21 square miles. Only 2,339 acres (or 40%) is in Cohasset. Consumer Confidence Report Map Produced by: Norfolk Ram Group Date: July 1, 2007 whERE yOUR dRInKInG watER COMES FROM www.cohassetwater.org WHERE YOUR DRInKInG WATER COmES FROm The Cohasset Water Department drinking water comes from two surface water supplies, Lily Pond (DEP ID# 065-01S), and the Aaron River Reservoir (DEP ID# 065-02S). Lily Pond has a maximum capacity of about 100 million gallons of water and is 52 acres in size. The 136 acre Aaron River Reservoir, which can hold a maximum of 550 million gallons of water, is used to supplement Lily Pond in times of high water demand. The watershed for Lily Pond and the Reservoir covers an area of 5,892 acres, 9.21 square miles. Only 2,339 acres (or 40%) is in Cohasset. The safe yield of our surface water supplies is 5.2 million gallons per day (gpd). Our average daily demand is about 800,000 gallons per day, and the maximum daily demand, in the summer, is 2.2 million gpd. Projections show that our existing water supply will be capable of meeting projected water system demands for the next 20 years or more. The Water Department has two well fields - the Ellms Meadow Well field (ID# 065-02G), which has been approved for up to 170,000 gallons per day. The well field will be reactivated in 2007. The Sohier Street Wells (ID# 065-01G & 03G) are currently out of service. WHAT THE WATER DEPARTmEnT IS DOInG TO PROTECT OUR WATER SUPPLY 1. Regularly monitors the water quality in tap water and in the surface water and groundwater of the watershed 2. Keeps track of know potential sources of contamination within the watershed and takes action to clean them up. 3. Reviews all proposed developments in the watershed. 4. Acquires land in the watershed to protect it from development. 5. Is in the process of implementing the recommendations of the Water Commission’s 2002 Surface Water Supply Protection Plan and the Source Water Assessment Program Report. 6. The Rain Garden Project which is projected to reduce pollut- ant loadings from Peppermint Brook into Lily Pond by 50%. 8 THInGS YOU CAn DO TO PROTECT YOUR WATER SUPPLY 1. Inspect your septic system every 1-3 years to make sure it’s working properly. Pump out your tank as necessary, but at least every 5 years. 2. Recycle used motor oil by bringing it to the Cohasset Recycling Transfer Facility or to the store where you bought it. NEVER pour used motor oil on the ground or down the drain! 3. Dispose of household hazardous waste properly at the next Household Hazardous Waste Day. NEVER pour hazardous materials down the drain on the ground, street, or storm drains. Call the Board of Health or visit www.ssrc.info to find out the next HHW day. 4. NEVER dump grass and yard waste into storm drains. Grass clippings and yard waste contain nutrients that can promote weed growth. 5. Reduce the use of fertilizers and herbicides on your lawn. Use only slow-release fertilizers. Have your soil tested to determine how much fertilizer to apply. Water fertilizer in with a hose and do not apply before a rainfall. Visit www.nsrwa.org and click on Greenscapes for more information on organic lawn care and maintenance. 6. Clean your car at a car wash instead of in your driveway. This will prevent any soaps, polishes, waxes and other chemicals from draining into storm drains and into the water supply. 7. Use water wisely. Avoid over-watering your lawn. 8. Watch out for any activities that might contaminate the water supply, and report and suspected contamination to the Water Department (781-383-0057), the Board of Health (781-383-4116), or the Fire Department (781-383-0260). SWAP REPORT On COHASSET The Department of Environmental Protection (DEP) has prepared a Source Water Assessment Program (SWAP) Report for Cohasset’s water supply sources. The SWAP Report identifies the key issues for our water supply protection as: protection of Zone A, protecting the Watershed outside Cohasset, public education , and control of residential uses that might contaminate the watershed. The report commends the Water System for mapping storm drains, conducting a study on the health of Lily Pond, and taking prelimi- nary steps to develop a lawn care program. As part of their ongoing efforts to protect the watershed, the Water Commission plans to implement all the SWAP recommendations and continue to implement the Surface Water Supply Protection Plan that was approved by the DEP in 2002. The complete SWAP report is available at the Water Department and on our website www.cohassetwater.org. For more information, call 781-383-0057. www.cohassetwater.org COnTAmInAnTS In DRInKInG WATER Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the EPA’s Safe Drinking Water Hotline (1-800-426-4791). The sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. As water travels over the surface of the land or through the ground, it dissolves naturally-occurring minerals and, in some cases, radioac- tive material, and can pick up substances resulting from the presence of animals or from human activity. Contaminants that may be present in source water include: Microbial contaminants, such as viruses and bacteria, which may come from sewage treatment plants, septic systems, agricultural livestock operations, and wildlife. Inorganic contaminants, such as salts and metals, which can be naturally-occurring or result from urban stormwater runoff, industrial or domestic wastewater discharges, oil and gas production, mining, or farming. Pesticides and herbicides, which may come from a variety of sources such as agriculture, urban stormwater runoff, and residential uses. Organic chemical contaminants, including synthetic and volatile organic chemicals, which are byproducts of industrial processes and petroleum production, and can also come from gas stations, urban stormwater runoff, and septic systems. Radioactive contaminants, which can be naturally-occurring or be the result of oil and gas production and mining activities. To ensure that tap water is safe to drink, the DEP and EPA prescribe regulations which limit the amount of certain contami- nants in water provided by public water systems. The Food and Drug Administration (FDA) and the Massachusetts Department of Public Health (DPH) regulations establish limits for contaminants in bottled water which must provide the same protection for public health. DEFInITIOnS 90th Percentile 9/10 were at or below this level pCi/L Picocuries per liter (radioactivity) ppb parts per billion, micrograms per liter (ug/l) ppm parts per million, milligrams per liter (mg/l) AL (Action Level) The concentration of a contaminant that, if exceeded, triggers treatment or other requirements which must be followed. MCL (Maximum Contaminant Level) Highest level of contaminant allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology. MCLG (Maximum Contaminant Level Goal) The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for margin of safety. MRDL (Maximum Residual Disinfectant Level) The highest level of a disinfectant allowed in drinking water. Disinfection is necessary to control microbiological contamination. MRDLG (Maximum Residual Disinfectant Level Goal) Level of drinking water disinfectant which there is no known or expected risk to health; do not reflect the benefits of the use of disinfectants to control microbiological contaminants. NTU (Nephelometric Turbidity Units) Measure of how clear the water is. ORSG Mass Office of Research and Standards Guideline Concentration of a chemical in drinking water, at or below which, adverse health effects are unlikely to occur after chronic (lifetime) exposure. SMCL Secondary Maximum Contaminant Level These standards protect the aesthetic qualities of drinking water and are not health based. TT (Treatment Technique) - 95% of all monthly samples taken must be less than/equal to 0.50 NTU Variances & Exemptions State or EPA permission not to meet an MCL or a treatment technique under certain conditions. vULnERAbLE POPULATIOnS WARnInG Some people may be more vulnerable to contaminants in drink- ing water than the general population. Immuno-compromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. EPA/CDC guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the Safe Drink- ing Water Hotline (1-800-426-4791). HEALTH EFFECTS InFORmATIOn Total Trihalomethanes (TTHMs) Some people who drink water containing trihalomethanes, in excess of the MCL over many years, experience problems with their liver, kidneys, or central nervous system. They may have an increased risk of getting cancer. 2006 COhaSSEt watER QUalIty RESUltS The Cohasset Water Department tests for over 80 contaminants on a regular basis, in accordance with State and Federal requirements. The following contaminants were the only ones detected in the most recent testing required. REGULATED CONTAMINANTS date(s) Collected highest detect Range detected highest average MCl or MRdl MClG or MRdlG viola- tion? (y/n) Possible Source(s) of Contamination INORGANIC Fluoride (ppm) Daily, 2006 2.57 0.56-1.47 ----4 4 No Additive to water to promote strong teeth Nitrate (ppm)5/25/06 0.23 --------10 10 No Runoff from fertilizer use; Leaching from septic tanks, sewage; Erosion of natural deposits Chlorine (ppm)Daily, 2006 1.83 .31-1.83 ----4 4 No Water additive used to protect public health by controlling microbes Barium (ppm)5/25/06 0.009 --------2 2 No Discharge of drilling wastes; discharge from metal refineries; erosion of natural deposits VOLATILE ORGANIC Total Trihalomethanes (TTHMs) (ppb) Quarterly, 2006 97 44 - 97 68.9 80 -----No Byproduct of drinking water chlorination Haloacetic Acids (HAA5’s) (ppb) Quarterly, 2006 7947 ND - 47 18.7 60 -----No Byproduct of drinking water chlorination RADIOACTIVE Gross Alpha (pCi/l)2/17/04 -1.3+/- 1.0 --------15 0 No Erosion of natural deposits Gross Beta (pCi/L) 2/17/04 2.9+/-2.2 --------50 0 No Decay of natural and man-made deposits Radium 226 2/17/04 0.3+/-0.2 --------0.1 0 No Erosion of natural deposits Radium 228 2/17/04 1.0+/-0.8 --------0.5 0 No Erosion of natural deposits SYNTHETIC ORGANIC Simazine (ppb)3/23/06 0.1 --------4 4 No Herbicide runoff Hexachlorocyclo- pentadiene (ppb) 6/3/03 0.1 -------- 50 50 No Discharge from chemical factories LEAD & COPPER (2) (20 sites sampled each) date(s) Collected 90th Percentile action level MClG # sites above al viola- tion? Possible Sources of Contamination Lead (ppb)9/15/04 9 15 0 2 of 20 No Corrosion of household plumbing systems Copper (ppm)9/15/04 0.80 1.3 1.3 0 of 20 No Corrosion of household plumbing systems; leaching from wood preservatives TURBIDITY tt lowest Monthly % of Samples highest detected daily value Violation?Possible Sources of Contamination Daily Compliance (NTU)0.3 ----0.20 No Soil Runoff Monthly Compliance At least 95%100%----No Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of water quality. * Monthly turbidity compliance is related to a specific treatment technique (TT). Our system filters the water so at least 95% of our samples each month must be below the turbidity limits specified in the regulations. UNREGULATED CONTAMINANTS (1) INORGANIC date(s) Collected Results average detected SMCl ORSG violation?Possible Sources of Contamination Sodium (ppm)7/6/06 26 --------20 No Runoff from use of salt on roadways to protect public safety Sulfate (ppm)7/6/06 6.0 ----250 ----No Natural sources (1) Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of unregulated contaminant monitoring is to assist EPA in determining their occurrence in drinking water and whether further regulation is warranted. Exceeding a SMCL or ORSG for an unregulated contaminant is not a violation. EDUCATIOnAL STATEmEnT COnCERnInG LEAD Infants and young children are typically more vulnerable to lead in drinking water than the general population. It is possible that lead levels at your home may be higher than at other homes in the community as a result of materials used in your home’s plumbing. If you are concerned about elevated lead levels in your home’s water, you may wish to have your water tested. Flush your tap for 30 seconds to 2 minutes before using tap water to reduce lead content. Additional information is available from the Safe Drinking Water Hotline, 1-800-426-4791.