A Comprehensive Wastewater & Nitrogen Management Plan for Oyster Pond

1. A Comprehensive Wastewater & Nitrogen Management Plan for Oyster Pond

2. How Did We Get Here? …. It was 25 years in the making In the mid 1980’s alert Falmouth residents noticed a profound change in our estuaries. • Mid 80s - Pond Watchers Citizen Monitoring program was initiated for Oyster, Little and Green Ponds. • 1987 - Town Meeting appropriated $5,000 “to conduct investigations of the physical, chemical, and biological characteristics” of Oyster, Little, and Green Ponds and to prepare a “comprehensive program for restoration, preservation and maintenance”. • 1989 – Collapsed culvert replaced with larger one causing profound changes to the pond • 1998 – Weir built to control pond salinity • 2006 – Listed as an impaired water body due to nutrients & pathogens on Mass Clean Water Act 303 (d) list • 2007 - Final Massachusetts Estuarine Project (MEP) report for Oyster Pond issued • 2008 Total Maximum Daily Loads (TMDLs) for nitrogen approved for Oyster Pond by the EPA and DEP. • Aug 2010 – Buzzards Bay Coalition & Conservation Law Foundation file suit against EPA for “failing to properly manage sources of nitrogen pollution like septic systems, stormwater, & wastewater treatment plant discharges on Cape Cod including Falmouth and Bourne.” Pond weeds in 2000

3. What is a Comprehensive Wastewater Management Plan?  A CWMP considers all wastewater treatment alternatives through a designated watershed region and prepares a cost effective preliminary plan focused on a defined water quality objective.  • A CWMP usually includes the following: • Needs Assessment – Assess current and future N sources • Develop & Screen Alternatives – ID & evaluate alternative treatment options • Evaluate Alternatives - for feasibility & $ • Identify Recommended Plan – produce prelim.engineered plan Final Product – A long term Plan for nutrient control (wastewater, storm water runoff, fertilizer) of the Pond.

4. The Benefits of a CWMP? • Gain opportunity for Zero % Financing • Increase cost sharing opportunities • Expand opportunities for expanded innovative alternatives – storm water run-off control, weir/outflow improvements, Mosquito Creek improvements

5. The Massachusetts Estuaries Project • Sets the Total Maximum Daily Load (TMDL) – greatest amount of a pollutant a water body can receive without impairment - for nitrogen in Oyster Pond • Is based on restoring oxygen levels in the water column to a 4 meter depth to restore benthic habitat for infaunal inhabitants. Target Concentration Nitrogen - 0.55 mg/L Target Nitrogen Controllable Load – 1.53 kg/day

6. An example of extreme nitrogen pollution Pirate’s Cove, Barnstable DEP defined status of Oyster Pond

7. Sources of Nitrogen to Oyster Pond To meet TMDL Targets, 70% of N Load must be removed

8. Oyster Pond is Unique:It is a Designed Brackish Water Estuary • Salinity is Maintained between 2 -4 ppt • Better Herring Habitat • Suppresses Nitrogen Activity

11. The Role of the Weir

12. Simple Mass Balance of Nitrogen Removal Septic System N Load ……………………3.61 kg/day Land Use (SW, Lawns) N Load …...…….1.46 kg/day Oyster Pond Current N Load…………5.07 kg/day Removalof Controllable Load N Load from Treetops - .41 x 3.61 = 1.48 kg/day N Load from WHRC - .04 x 3.61 = .14 kg/day Load from Remaining Residential Homes 1.99 Removal by Denite System x .50 = 1.00 kg/day Load from Land Use (SW, Lawns) .63 x 1.46 = .92 kg/day Total Removal = 3.54 kg/day 5.07 – 3.54 = Target Load = 1.53 kg/day

13. Possible Comprehensive Wastewater and Nutrient Management Plan Budget for Oyster Pond I. NEEDS ASSESSMENT A.   Hydrology update       Morraine region needs some Monitoring Wells for Mapping           $ 15,000 B. Sources of Nitrogen and Phosphorus         Trying to add P into budget                               $ 10,000 II. DEVELOP & SCREEN ALTERNATIVES  C.  Wastewater and Nutrient Control- Design and permitting review                                                      1. Community Small Plant (prob. Cluster)    Discharge and system outside OP recharge zone                 (flow under 16,000 gpd)                                                                                                 $ 85,000            2.  Small Cluster ( Flow, 12,000 gpd)                                                                                  $ 30,000            3.  Focused denitrification (60-64 units)             High GWflow region                                  $ 15,000            4.  Diffuse Residential (110 units)                                                                                        $ 35,000                  a. Residential turnover-denitrification                  b. Plume interception/barrier            5.  Weir control                                               Salinity control/ N/P ratio/Aquatic Vegetation  $ 20,000            6.  Biomass out-migration, algae                    Herring Propagation                            $  5,000             7.  Land Use - Stormwater runoff, Fertilizer    Roadway, Creek, Lawns, Leaf fall                  $ 15,000  III. EVALUATE ALTERNATIVES      D. TMDL modeling of alternatives                         Computer runs                                        $ 40,000  IV. IDENTIFY RECOMMENDED PLAN      E.  Trunk River Outflow Improvement                    Maint. Dredging, Eel grass screen                $ 20,000 F. Final Report $10,000    $  300,000

14. Examples of Small Plant Cluster Systems – Innovative DEP Approved

15. CMNWP Best Possible Time Line • April 2011 – Town Meeting Vote on article • May 2011 – Town Election vote on tax override • July 2011- Request for Proposals (RFPs) go out to public • August 2011 - RFPs reviewed by the Town • September 2011– Consultant Selected, contract signed, initial mtg. • 2012 – Needs Assessment Report • 2012 - Develop & Screen Alternatives Report • 2013 - Evaluate Alternatives &Identify Recommended Plan (Prelim. Engineering Plan) • 2014 – RFP issued for Full Engineering Plan, Engineer Selected • 2015 – Final Engineered Plan developed, Permits issued. • 2016 – Project Ground Breaking