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PHILADELPHIA WATER DEPARTMENT BAXTER WATER TREATMENT PLANT (PWSID# 1510001) SOURCE WATER ASSESSMENT REPORT SECTION 2: DELAWARE RIVER INTAKE This report was produced for the Pennsylvania Department of Environmental Protection in accordance with the Source Water Assessment and Protection Plan. Prepared by The Philadelphia Water Department June 12, 2002 With support from: Bucks County Water and Sewer Delaware River SWA Philadelphia Suburban Water Company Pennsylvania American Water Company Pennsylvania Department of Environmental Protection Camp Dresser & McKee PADEP Contract: ME350056 Executive Summary - Baxter WTP Intake Source Water Assessment The 1996 Safe Drinking Water Act Amendments required the assessment of all source water supplies across the country to identify potential sources of contamination, the vulnerability and susceptibility of water supplies to that contamination, and public availability of the information. In response to this charge, the Delaware River Source Water Assessment Partnership, comprised of the Pennsylvania Department of Environmental Protection, the Philadelphia Water Department, the Philadelphia Suburban Water Company, and the Pennsylvania American Water Company, and the Bucks County Water and Sewer Authority conducted the assessment with stakeholders to identify water supply protection priorities in the Delaware River Watershed. The following summary includes two main sections. One section discusses the various characteristics and observations made through collection of watershed wide information. The remaining section provides a brief listing of the main recommendations based on the results of the analysis. High Protection Priority Issues and Activities Overall, the following activities were identified as having high priority for protection efforts to address: S Sanitary Sewer Overflows of raw sewage from sewer collection systems, sewage lift stations, and manholes from upstream communities S Urban, residential, and agricultural runoff from various areas of the watershed, mostly located in tributaries such as the Pennypack Creek, Poquessing/Byberry Creek, Neshaminy Creek, Rancocas Creek, Lehigh River, and Musconetcong River. S Discharges from municipal and industrial sources such as sewage treatment plants and chemical manufacturing facilities between Camden and Trenton. S Spill and accidents from cars, tanker trucks, railroad cars, pipelines, tire piles, and fires at industrial facilities near the river and its tributaries Observations & Characterization S Raw water is gravity fed via tidal elevation changes from the Delaware River at a daily average rate of 175 million gallons per day (MGD) with maximum capacity of 320 MGD. S The Baxter Water Treatment Plant serves approximately 750,000 customers in Northeastern Philadelphia and Lower Bucks County. S The water supply intake is located at Delaware River mile 11. It is the farthest downstream public water supply located on the Delaware River in Pennsylvania. S The drainage area of the basin above the Baxter Intake is approximately 7,500 square miles. Land use of the area just upstream of the intake is primarily residential and light/heavy industrial. 1 S Water withdrawn from the Delaware River is coagulated, settled, filtered, and disinfected with chlorine to make it safe prior to distribution to customers. Drinking water quality meets or exceeds all state or federal requirements. S Delaware River water quality is monitored to assess potential health risks, aesthetics, and treatment requirements. S The Philadelphia Water Department routinely monitors pH, color, alkalinity, hardness, total dissolved solids, conductivity, turbidity, coliform, Giardia and Cryptosporidium, total organic carbon, UV absorbance, bromide, nitrogen, phosphorus, iron, manganese, sulfate, chloride and sodium at their Baxter Intake. Many other parameters are monitored as part of special studies. S Turbidity and other suspended contaminants in the river tend to increase as a function of precipitation, runoff and river flow. S Salt levels in the river appear to fluctuate seasonally, perhaps in response to application of road salts during the winter. S Over the past decade, levels of alkalinity, conductivity, sodium, chloride, bromide, iron, manganese, nitrate and turbidity in the Delaware River have increased at the Baxter Intake. Increased pollution from runoff is the most likely source of these changes. S Stream impairments in the Lower Delaware River Watershed are primarily caused by stormwater runoff from urban and suburban areas. S Almost 6,000 potential point sources were identified within the 2,060 square mile Baxter Intake. Most of these potential sources do not – and will never – discharge to Delaware River. They have been identified so that water suppliers can assess their potential impacts upon the water supply, and identify appropriate protective measures. S Over 1,700 RCRA facilities are located upstream of the Baxter Intake. Most RCRA facilities are not large quantity generators. S Sewage systems, dry cleaning plants (except rug cleaning), and gasoline service stations are most common. S Volatile organic chemicals, petroleum hydrocarbons, and SOCs were the most frequently reported contaminants. S The Delaware River Runoff Loading Model was developed to estimate contaminant loadings to the river from storm runoff. S The model used the physical characteristics of the sub-watersheds, meteorological data, updated land use information, and event mean concentrations for the nine parameters of interest to estimate average daily contaminant loadings within each of the Baxter Intake’s zones of contribution. S The developed land areas associated with industrial/commercial land use and residential uses were estimated to contribute the highest per acre loadings of most of the 2 contaminants evaluated, including disinfection by-products, metals, nutrients, petroleum hydrocarbons, salts, and coliforms. S Unit cryptosporidium and turbidity loadings were higher from agricultural areas. S A series of screenings was used to identify those sources that have the greatest potential to affect water quality at the Baxter Intake. S Five non-conservative contaminant categories and five conservative contaminant categories were selected to represent all potential contaminants. S For each category, a threshold value indicative of the significance of the concentrations of contaminants that could result from a potential spill or discharge was defined. S EVAMIX, a multi-criteria software package was used to prioritize the potential significance of each of the potential point sources within Baxter’s Zone A and Zone B, and to evaluate the potential significance of non-point sources estimated by the Delaware River Runoff Loading Model. S NPDES and nonpoint source discharges within the Baxter Intake’s Zone A and Zone B were determined to have the highest protection priorities in the watershed. S The potential significance of each source of contamination was designated A (potentially significant source of highest protection priority) through F (Potential source of lowest protection priority). Those sources ranked A through C are potentially significant sources of contamination to the Baxter Intake. S All of the highest ranked sources are either NPDES sites or stormwater loadings from specific sub-watersheds. S Contaminant sources actually discharging to the river (e.g., NPDES permitted point sources, or stormwater runoff) are estimated to have greater potential significance than those with only the potential to release contaminants to the river (e.g., a spill or leak). S EVAMIX was also used to rank potential sources for each contaminant category. Protection Recommendations S Overall, the primary protection areas to focus PWD’s protection efforts to protect and improve PWD’s water supply include the tidal areas of the Delaware River between Trenton and Philadelphia/Camden. S Non point source protection should be focused in the Pennypack Creek, Poquessing/Byberry Creek, and Neshaminy Creek areas as well as portions of the Muscentong, Pohatcong, Lehigh Rivers. However other parts of the watershed may need limited attention for contaminant specific issues. 3 Based on the results of the susceptibility analysis, water quality data, and stream impairments, it is clear that the potential impacts from point source discharges need to be addressed from the discharges along the main stem of the Delaware River from Camden to Trenton. Efforts to reduce these impacts would require the following components: S Enforcement of compliance requirements for industries and municipalities discharging wastewater into the protection priority corridor between Camden and Trenton; S Facilities Management Plans in Montgomery and Bucks Counties. In addition, the sewage facility related issues from the SWAs should be incorporated into the ACT 537 plan with emphasis on monitoring and measuring progress towards addressing identified problems; S Development of a coordinated regional protection plan that will be adopted by water suppliers, planning commissions, and municipalities for establishment and protection of sensitive and high priority protection areas to multiple and overlapping water supply areas between Camden and Trenton; S Development of mechanism or framework to address source water protection and non- point source issues in the Lower Delaware River Basin area. The DRBC has a number of water resources and watershed/TMDL related committees, but they are focused only on source water protection concerns. Finding

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