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decline. Dr. Howes also reported that benthic animals, such as shellfish, are lost with increased levels of <br /> nitrogen. Loss of the base of the food chain could result in larger losses such as birds, flounder or <br /> possible fish kills. A chart depicted the losses of the benthic fish and highlighted major losses occurring <br /> from July to October and reviving December to June. Dr. Howes also discussed macro-algal <br /> accumulations in Popponesset Bay and Waquoit and their ability to create a low oxygen environment by <br /> smothering the bottom of the bay. Images showing the drifting of macro-algae were shared and Dr. <br /> Howes stated that it was an indicator of the Bay's death. <br /> A study conducted in Falmouth highlighted the importance of the location of discharge sites. The <br /> wastewater treatment facility located in West Falmouth Harbor discharged treated effluent to the beds and <br /> the plume traveled to the harbor in 7-9 years. When the plume arrived at the harbor,the nitrogen loading <br /> doubled in a single year. More than 501/o of the eelgrass population was killed in 5 years. Nitrogen <br /> management is the only way to restore degraded estuarine habitat. Nitrogen can be managed by <br /> increasing the tidal exchange, removing nitrogen while it is being transported or controlling nitrogen at <br /> the source. <br /> Regarding the status of the two Mashpee systems,Dr. Howes reported that the upper region of the estuary <br /> is the most sensitive with the greatest level of nutrients, and is the farthest from the inlet and where the <br /> nitrogen enters. The Estuary Reports for both bays are complete and the Massachusetts DEP has <br /> converted them to TMDL reports. EPA has accepted both TMDLs and scenarios have been identified for <br /> the two bays. The Estuaries Project is a joint project between Massachusetts DEP(regulatory) and <br /> SMaST (science&testing)partnering directly with municipalities in Southeastern Massachusetts, <br /> including Barnstable County and the Cape Cod Commission. USGS conducts ground water modeling and <br /> watershed delineations. The purpose of the project is to set nitrogen thresholds for TMDLs and to create <br /> new tools for towns to reduce nitrogen levels at a lower cost and new tools to conduct assessments, such <br /> as Mashpee's unified database. Of the 89 Estuary Projects, 42 are complete. Ali systems will require <br /> some form of wastewater treatrnerrt. The Estuary Project does not use the modeling approach, but a data <br /> driven approach utilizing site specific data to create a series of models. <br /> In Popponessett Bay,Mashpee is monitoring water quality through the Town and the Wampanoag Tribe. <br /> Dr. Howes' chart compares the high quality Nantucket Sound waters entering Popponessett Bay to the <br /> poor to moderate quality water in the inlet of the bay. Another image depicting the origins of the <br /> watershed was shared with the group to identify the critical sources of the nitrogen. Dr. Howes noted that <br /> a house count was not used but that an approach was developed utilizing water units for all homes in the <br /> watershed area. Dr. Howes referenced an image depicting the total nitrogen level that could not be <br /> controlled since it comes from the atmosphere, compared to the local nitrogen load from septic systems <br /> totaling 80%. Ground water has been tracked and it laas been determined that 80%of watershed water, <br /> reach the bay in 10 years. However, not all nitrogen will reach the bay since 40%of the watershed runs <br /> through ponds, wetlands or bogs and 87%of the watershed will contribute to a river. A natural <br /> derritrizication system extending over a 6 month-2 year period, allows some removal of nitrogen as it <br /> travels through the ponds. Dr. Howes reported that there is approximately 40%-59% uptake of nitrogen <br /> before the water enters the bays. These statistics allow planners to better assess sewering needs and <br /> identi'ing the most effective placement of sewering- <br /> Dr. Howes discussed the poor water quality in Popponessett Bay that extends to the midway point during <br /> the outgoing tide and the resulting effect on eelgrass beds that have disappeared.. Dr. Hawes also noted <br /> that if the existence of eelgrass cannot be proven, then the TMDL can not regulate the restoration of <br /> eelgrass, such as in Shoestring Bay. The EPA and DEP agreed. Dr. Howes also discussed benthic habitat <br /> 3 <br />