80 



BIOLOGICAL REPORT 31 



increasing nutrient inputs from residential develop- 

 ment and upstream agricultural activities are of grow- 

 ing concern to the community. 



Dartmouth. A relatively large town, Dartmouth 

 includes the historic seaport village of Padanaram 

 in its southeast corner. The town maintains a sec- 

 ondary treatment plant built in 1 970 (to be expanded 

 sometime in the 1 990's) that discharges effluent into 

 Buzzards Bay south of Salters Point. A portion of 

 the watershed for the East Branch of the Westport 

 River lies within the town's boundaries. Increased 

 nutrient loading from development is a concern in 

 this area; Lake Noquochoke, lying along one of the 

 source rivers for the East Branch, currently suffers 

 from eutrophication, with overproduction of aquatic 

 plants due to excessive nutrient loading. 

 Apponagansett Bay is also subject to high nutrient 

 loads and resulting low oxygen conditions. 



New Bedford. This city has the largest popu- 

 lation in the region, with most of its land area (ap- 

 proximately 5,261 ha) developed. The Achushnet 

 River (along the city's southeast border) has been 

 heavily polluted by industrial and organic wastes. 

 High levels of coliform bacteria, heavy metals, and 

 polychiorinated biphenyls (PCB's) are found in the 

 river waters and sediments. The sources of this 

 pollution range from runoff and residential inputs in 

 the upper portions of the river to direct industrial 

 discharges and combined sewer overflows in the 

 inner harbor (lower Acushnet River). From 1920 

 to 1 973, wastewater was discharged directly into 

 New Bedford Outer Harbor; since 1974 New 

 Bedford has maintained a municipal wastewater 

 treatment facility that continues to discharge primary 

 effluent into the harbor, including storm-related 

 wastewater. Also, there is a growing concern over 

 the potential contamination of groundwater from the 

 existing municipal landfill, which contains more than 

 225,000 kg of capacitors and barrels containing 

 PCBs. 



Fairhaven. As with many of the towns along 

 Buzzards Bay, Fairhaven historically maintained a 

 seaport. Bordering Buzzards Bay and the Acushnet 

 River across from New Bedford, Fairhaven has 

 experienced rapid residential and commercial 

 growth in recent years. Fairhaven drains by the 



Acushnet River basin in the west, the Mattapoisett 

 River basin in the northeast, and the Nasketucket 

 River basin in the central portion of the town. Run- 

 off of pollution from municipal and industrial sources 

 into the Acushnet River has resulted in periodic low 

 oxygen levels and high bacteria counts, exacerbated 

 by inputs from treatment plant effluent and runoff 

 from both New Bedford and Fairhaven. 



Mattapoisett. Mattapoisett is a small coastal 

 residential community. The town historically sup- 

 ported agriculture and shipbuilding but now is pri- 

 marily residential with a seasonal influx of tourists 

 during the summer months. The southern portion of 

 the town drains directly into the bay through sev- 

 eral small streams. Most of the town drains into the 

 Mattapoisett River basin except for a small part in 

 the northeast corner, which is part of the Sippican 

 River basin. Mattapoisett River discharges into 

 Mattapoisett Harbor; both have relatively high wa- 

 ter quality without significant municipal or industrial 

 discharges, although the harbor is occasionally 

 closed for shellfishing because of high numbers of 

 coliform bacteria. The source of this bacteria is pri- 

 marily from discharge at the town pier of a small 

 stormwater and sanitary collection system. High lev- 

 els of nutrients and coliform have been measured in 

 the stream that drains the center of the town, pre- 

 sumably from septic system leachate and domestic 

 waste discharge. Runoff from nearby dairy farms is 

 also identified as a source of pollution. Natural 

 sources, however, cannot yet be ruled out. 



Marion. Marion is a small rural community on 

 the upper bay with a large seasonal influx of sum- 

 mer tourists. Most of the town's watershed drains 

 directly to the bay through a series of streams and 

 Sippican Harbor. Water quality has historically been 

 high in all but a small portion of the Sippican River 

 found to contain high mercury concentrations origi- 

 nating from the former use of mercury-based anti- 

 fouling paints. Marion's wastewater treatment fa- 

 cility discharges into a small stream that enters 

 Aucoot Cove. Studies conducted in Aucoot Cove, 

 the recipient of the town's municipal wastewater 

 treatment plant, indicate this area maintains rela- 

 tively high water quality (Howes 1 993). The former 

 town landfill was graded and planted to reduce 



