Executive Summary Draft Comprehensive Wastewater
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EXECUTIVE SUMMARY DRAFT COMPREHENSIVE WASTEWATER MANAGEMENT PLAN/ DRAFT ENVIRONMENTAL IMPACT REPORT FOR THE LITTLE POND, GREAT POND, GREEN POND, BOURNES POND, EEL POND, AND WAQUOIT BAY WATERSHEDS ES.1 BACKGROUND The Town of Falmouth (Town) is completing this Draft Comprehensive Wastewater Management Plan and Draft Environmental Impact Report (DCWMP/DEIR) and Notice of Project Change (NPC) Document to provide a comprehensive strategy for wastewater management for the Little Pond, Great Pond, Green Pond, Bournes Pond, Eel Pond, and Waquoit Bay watersheds. These watersheds comprise the Planning Area for the Comprehensive Wastewater Management Planning (CWMP) Project. Figure ES-1 illustrates the location of the Town of Falmouth on Cape Cod and the Planning Area in the eastern half of the Town and extending into the towns of Mashpee and Sandwich. The plan is for a 20-year period (year 2015 to 2035) with a 40-year perspective (extending to year 2055) on the ultimate buildout for the Town and the need of the Towns of Falmouth, Mashpee, and Sandwich to meet Nitrogen Total Maximum Daily Loadings (TMDLs) for these watershed areas. The starting year (2015) of this Planning Period is estimated as the first year of operation of newly constructed wastewater facilities for this area. This DCWMP/DEIR documents the many evaluations and reports that were completed for this project. It also documents the recommended plan for the wastewater management system, as well as non-wastewater management recommendations. It provides an environmental impact analysis that demonstrates the significant environmental benefits of this Project. This DCWMP/DEIR is the proposed plan to remediate the water quality and marine habitat of the salt ponds and bays in the Planning Area that have been impacted by excessive nitrogen loadings from the watersheds, predominantly from existing septic system discharges. This plan will need to be implemented through adaptive management to provide the most effective nitrogen mitigation and the most cost-effective implementation. This means that the plan is developed in a flexible format to allow changes in the implementation as new Town of Falmouth, MA ES-1 Draft Comprehensive Wastewater Management Plan and Draft Environmental Impact Report 7104510.6 technologies prove their feasibility, performance testing demonstrates the true performance of the installed facilities, environmental monitoring indicates improvement in the marine water quality, and as new regulations/laws/building codes are passed to allow new approaches. There are components of this plan which need further coordination and agreement. The most significant needed component is an agreement with the Massachusetts Military Reservation (MMR) to allow Falmouth to construct a new Wastewater Treatment Facility (WWTF) on their property near the existing Otis Air Force Base (AFB) WWTF and the Regional Solid Waste Management Facility. An agreement to site a new WWTF to serve the Planning Area, and possibly the neighboring Towns of Mashpee, Sandwich, and Bourne, as well as the MMR itself, is not yet complete. Significant progress has been made toward an agreement over the past year, but additional discussions, negotiations, and agreement are needed. Discussions are also needed with Massachusetts Department of Environmental Protection (MassDEP) on the proposed treatment, recharge and water-reuse system, and the adaptive management approach proposed as part of the plan. This document is prepared for review by Massachusetts Department of Environmental Protection (MassDEP) and as part of the Massachusetts Environmental Policy Act (MEPA) and Cape Cod Commission (CCC) Development of Regional Impact (DRI) joint review process. A Notice of Project Change (NPC) is also included in this document because detailed evaluations have been completed (and reported in this document) that were not originally scoped in the CWMP Environmental Notification Form (ENF) and ENF approval certificate. ES.2 SUMMARY OF WASTEWATER PROBLEMS AND NEEDS IN THE PLANNING AREA The identification and understanding of the wastewater related problems in the Planning Area has been a long process. The first recommendation of sewer extensions to portions of the Planning Area date back to May 1981 in the Wastewater Facilities Plan by CDM and the Environmental Impact Report by USEPA. That plan recommended sewering the densely developed Maravista Peninsula located between Little and Great Ponds, as well as the Falmouth Heights area located west of Little Pond. That sewer extension was planned to be the second phase of the larger wastewater project Town of Falmouth, MA ES-2 Draft Comprehensive Wastewater Management Plan and Draft Environmental Impact Report 7104510.6 that constructed the original Blacksmith Shop Road WWTF, connected the Woods Hole sewer system to the Blacksmith Shop Road facility, eliminated the Woods Hole ocean outfall, and provided sewer extension to Main Street, Inner Harbor, and Falmouth Beach areas of Falmouth Center. The second phase of that project was never completed due to problems with the original Blacksmith Shop Road WWTF. The second recommendation of sewer extensions to portions of the Planning Area dates to January 2001 in the Wastewater Facilities Plan and Environmental Impact Report by Stearns & Wheler. That plan identified that excessive nitrogen loadings to the watersheds of Little Pond and Great Pond were impacting water quality to the two salt ponds and that sewer extension was the best solution. That plan indicated that the nitrogen limits for the two ponds were needed before sewer extension planning could proceed further. That plan also recommended an upgrade and expansion of the Blacksmith Shop Road WWTF (completed in 2005), sewer connection to the Falmouth High School (completed in 2007 - 2008), sewer extension to the North Davis Straits Planning Area (Falmouth Mall and surrounding area), sewer extension to the Scranton Avenue Area, and sewer extension to the West Falmouth Harbor area. These last three sewer extensions have not yet been completed and it is noted that the North Davis Straits area is within the Planning Area for the current project. This DCWMP/DEIR includes the implementation timeline of these three previously approved sewer extensions coordinated with the implementation timeline of the wastewater facilities for the Planning Area. The third recommendation of sewer extensions for portions of the Planning Area dates to March 2001 with the completion of the Ashumet Plume Nitrogen Offset Program Detailed Analysis of Feasible Corrective Actions by the team of Horsley & Witten, Inc.; UMass School of Marine Science and Technology (SMAST); and Applied Coastal Research and Engineering, Inc. This recommendation did not proceed (in part) due to the need for Nitrogen Total Maximum Daily Load (TMDL) limits for the salt ponds. The nitrogen TMDLs developed by the Massachusetts Estuaries Project (MEP) and promulgated by the Environmental Protection Agency since 2001 documented the following problems in the salt ponds of the Planning Area: High concentration of nitrogen in the marine water that has led to excessive algae production and eutrophic conditions. Town of Falmouth, MA ES-3 Draft Comprehensive Wastewater Management Plan and Draft Environmental Impact Report 7104510.6 Loss of water clarity from the suspended algae which has led to loss of rooted eel grass on the floor of the estuaries. Deposition of algae in the estuaries which has further damaged eel grass beds, smothered shellfish resources, and depleted dissolved oxygen concentrations in the estuary and severely impacted the benthic communities on the estuarine floor. These TMDLs identified threshold nitrogen concentrations for these salt ponds and calculated the amount of existing wastewater nitrogen that would need to be removed to meet the threshold concentrations. The percentages of existing wastewater nitrogen loading (from existing septic systems) that needs to be removed to meet the nitrogen TMDLs is illustrated on Figure ES-2. This figure also illustrates the existing areas of Town served by sewers and the three potential wastewater treatment plant sites evaluated as part of this project. It is noted that the TMDLs have been completed for all coastal ponds in the Planning Area except for the western portion of Waquoit Bay (“Waquoit West”). TMDL completion for Waquoit West is expected in 2010 or 2011. In an effort to proceed with the wastewater planning for the total Planning Area, Stearns & Wheler used the existing wastewater nitrogen removal percentages from the adjacent Bournes Pond watershed as a planning assumption of the removals needed for Waquoit West. The wastewater removals shown on Figure ES-2 are for the “existing conditions” in the approximate time period of 2003 to 2004 as documented by the Massachusetts Estuaries Project. Additional land use growth has occurred and is expected in this area, and when the ultimate buildout is projected for this area, the needed wastewater nitrogen removals are even greater. Figure ES-3 illustrates the percentage of future wastewater nitrogen loadings that need to be removed to meet the nitrogen limits. These are very stringent limits that can only be met by sewering the majority of the Planning Area, advanced wastewater treatment, and careful recharge in selected locations of the Planning Area that can accommodate the return flow and remaining nitrogen estimated at 1 to 3 mg/L total nitrogen. This figure also illustrates planned and proposed sewer areas Town-wide.