11/15/2011 SEWER COMMISSION Minutes

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Comments and Justification - FY20:12 Sewer Commission EIP Mashpee is the fastest-growing town on Cape Cod. At the same time, it is located almost entirely within the watersheds of two shallow nitrogen-sensitive estuaries, Popponesset Bay and Waquoit Bay. The estuarine systems of both bays have shown significant signs of degradation attributable to excessive inputs of nitrogen. Both have been seriously impacted by algae blooms nurtured by excessive nitrogen levels. Wastewater effluent discharged to groundwater has been identified as the largest source of the nitrogen that reaches both bays. Impacts have included fish kills, the almost total loss of formerly extensive eelgrass beds, the deposition of a thick mat of macroalgae and decomposed algae at the bottom of the many portions of the bays and the almost total loss of a formerly healthy bay scallop population. The Mashpee River estuary has been most seriously impacted. A thick layer of organic muck at its bottom has made the river virtually uninhabitable by most shellfish and prompted increasing complaints by nearby residents of odors, "pea soup" water and associated water quality complaints. A watershed nitrogen loading analysis released by the DEP Massachusetts Estuaries Program (MEP) in September 2004 confirmed extreme nitrogen overloading of the poorly-flushed Mashpee River estuary and of all the sub-embayments to Popponesset Bay (Ockway Bay, Mashpee River, Shoestring Bay), as well as the upper half of the Bay itself. Based on the report, Mass. DEP has established (August 2005) nitrogen reduction targets for each sub-embayment that have been incorporated into nitrogen TMDLs (Total Maximum Daily Loads) enforceable by USEPA and DEP. A similar MEP study of the Hamblins Pond / Jehu Pond / Great River and Quashnet (Moonakis) River sub- embayments of Waquoit bay was completed in January 2005, also resulting in TMDLs published for those water bodies in October 2005. The Town will be expected to develop regulatory and infrastructure improvements to meet those TMDL targets. Both MEP reports recommend sewering of large portions of the Town as the only feasible means of meeting the TMDL targets, In response to the nitrogen overloading problem, the May and October 1999 Town Meetings voted $445,000 to develop a Watershed Nitrogen Management Plan / Effluent Pipeline Preliminary Design study to determine the most appropriate, cost-effective and politically feasible means, including municipal wastewater facilities, along with other appropriate facilities and management structures, required in order to address the nitrogen overload problem. The. Engineering firm of Stearns &Wheler (now GHD) and the School of Marine Science &Technology at UMass-Dartmouth were contracted to develop the plan. Advice by DEP to wait for the nitrogen targets to be established by the Mass Estuaries Program delayed completion of the plan for a number of years, but work was restarted in late 2006, with completed project reports regarding Needs Assessment (April 2007), Technology Screening (November 2007) and Draft Alternative Scenarios Analysis and Site Evaluation (March 2008). Five alternative scenarios for developing wastewater facilities have been reviewed by U-Mass-Dartmouth with regard to their effectiveness in meeting the established TMDL targets. Upon delivery of their final report at the December 15, 2009 Sewer Commission meeting, the Commission, after approximately 6 months delay caused by re-organization and education of new members, has begun the process of developing I or 2 more refined plans based on the most effective scenarios, to include more detailed plans and cost estimates, with completion of the study and a recommended plan now anticipated in late 2011. The plan will recommend both facilities and management options;which will include development of a municipal sewer system, likely based in part on existing private systems and neighborhood cluster facilities in addition to 1-3 larger municipal treatment plants and wastewater collection systems, and facility management approaches, along with stormwater facilities and other traditional or innovative approaches to nitrogen reduction or removal. The Plan is expected_ to include conceptual facilities designs, estimated costs, financing mechanisms, pricing / charges, regulatory changes and other items relevant to the establishment of a municipal sewer system and management of nitrogen loading to the watersheds. Once the plan is completed, firmer costs for design and construction of the three proposed CIP projects will be possible. One of the specific projects under study (Project #1) is the potential for relocation of nitrogen discharge, via an "Effluent Relocation Pipeline", from existing treatment plants and developments in the Popponesset and 1