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1.0 INTRODUCTION <br /> Pleasant Bay is a coastal estuary that, like many on Cape Cod, is threatened by excessive loading <br /> of nitrogen from development within its watershed. The primary source of nitrogen within the <br /> watershed is wastewater from on-site septic systems. A secondary source is fertilizers applied to <br /> lawns, gardens, golf courses, and athletic fields. <br /> This project, funded through a grant to the Pleasant Bay Alliance from the Cape Cod Water <br /> Protection Collaborative,has been designed to investigate the following fertilization issues: <br /> • What is the current contribution of nitrogen from fertilizers in the Pleasant Bay <br /> Watershed and how significant is it in comparison to that provided by wastewater <br /> discharges? <br /> • What current regulations exist in the four Pleasant Bay watershed towns (Brewster, <br /> Chatham,Harwich, and Orleans)that support the management of fertilizer use? <br /> • Are there examples from other communities around the country that could be considered <br /> for use in the Pleasant Bay watershed? <br /> • What specific recommendations should be considered for Pleasant Bay;what issues exist <br /> with their implementation; and what credit towards the Total Maximum Daily Loads <br /> (TMDLs) can be achieved for each? <br /> The Massachusetts Estuaries Project(MEP)has conducted a detailed land use assessment to <br /> quantify the nitrogen loading to Pleasant Bay(MEP, 2006). In addition,MEP developed a <br /> hydrodynamic model to predict the level of nutrient loading that is protective of the habitat <br /> within the Bay(MEP model). The critical loads or TMDLs are currently being used as targets <br /> that must be met by towns within the watershed as part of their watershed planning efforts. A <br /> significant reduction below current loading rates is needed to meet the TMDLs. <br /> The goal of this project is to evaluate how managing fertilizer use within the watershed can <br /> contribute to meeting the TMDLs for Pleasant Bay or its sub-watersheds. While wastewater <br /> management is the primary approach to meeting the TMDLs, fertilizer management may support <br /> these efforts by reducing infrastructure needs of subsequent phases of a respective towns' <br /> Comprehensive Wastewater Management Plan(CWMP) implementation, or may provide a <br /> viable alternative in limited number of sub-watersheds where the control of fertilizers may be <br /> sufficient to meet a TMDL. The sub-watersheds where this will be most effective are those <br /> where nitrogen loading is predominately a result of fertilizer use(e.g., golf courses), rather than a <br /> combination of fertilizer use and wastewater(e.g., residential properties). <br /> 2.0 CURRENT FERTILIZER LOADINGS TO PLEASANT BAY <br /> Based on a review of the MEP model for Pleasant Bay,the Horsley Witten Group Inc. (HW)was <br /> able to quantify fertilizer use and associated nitrogen loading for the Pleasant Bay watershed. <br /> HW reviewed the loading assumptions used within the model and separated loads by nitrogen <br /> fertilizer source, including existing and future residential properties,golf courses,and municipal <br /> parcels such as athletic fields and playgrounds. HW also identified three sample sub-watersheds <br /> with different land use characteristics to analyze existing nitrogen loads for these watersheds <br /> Pleasant Bay Fertilizer Management Plan 1 Horsley Witten Group,Inc. <br /> Final Report December 2010 <br />