The goal of the Clean Water Act (cwa) is to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters
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- Primary and Secondary Contact RECREATION and aesthetics
WMA water withdrawal SummarySee Aaron River (Segment MA94-28) and Herring Brook (Segment MA94-29) segments for upstream water withdrawals. OtherAccording to the Wetland Protection Act Regulations Variance for the Greenbush Commuter Rail Restoration Project in Scituate, a bridge crossing of Bound Brook will need to be replaced with a box culvert, new abutments and improved stormwater management. Scour protection is proposed at the mouth of the culverts in Bound Brook. Stormwater runoff also will be discharged into Bound Brook from the proposed North Scituate Station. Under present conditions (commercial buildings, parking and public open space), the stormwater is not detained and receives little or no water quality treatment. Under the proposed conditions (the North Scituate Railroad Station), MBTA will use best management practices including street sweeping, deep-sump hooded catch basins and Downstream Defenders® treatment units (MassDEP 2004b). Use AssessmentAquatic LifeHabitat and FlowThere is a flow control structure at the upstream side of Beechwood Street, Cohasset. When the boards are raised, the flow of Aaron River is diverted into Herring Brook and into Lily Pond (public water supply system operations). The poorly designed, deteriorating notched weir-pool fish ladder at Hunters Pond is impassable (Reback et al. 2004). Chemistry – waterIn 2001 DWM conducted water quality sampling at one station (AR101) on Aaron River upstream from the outlet control structure at Beechwood Street, Cohasset (Appendix A). In-situ measurements of DO, % DO saturation, temperature, pH, conductivity, and TDS were recorded on seven occasions from June to October. Samples were collected on five occasions for total phosphorus, ammonia-nitrogen, nitrate-nitrite nitrogen, chloride, alkalinity, and hardness. The results are summarized below. Dissolved oxygen and percent saturation DO measurements by DWM ranged from 2.0 to 5.9 mg/L with the percent saturation ranging from 24 to 56%. Only one of six measurements did not meet the water quality standard of 5.0 mg/L. Temperature Temperature measurements ranged from 13.9ºC in October to 28.0ºC in June. pH, alkalinity and hardness pH was low ranging from 5.5 to 6.1 SU as were alkalinities (4 to 7 mg/L) and hardness (14 to 18 mg/L). Conductivity Specific conductance measurements ranged from 119 to 130 µS/cm. Total dissolved solids TDS measurements ranged from 76.1 to 83.3 mg/L. Nutrients Total phosphorus concentrations ranged from 0.031 to 0.059 mg/L. Ammonia-nitrogen concentrations were <0.02 mg/L for all unqualified samples and nitrate-nitrite nitrogen concentrations ranged from <0.06 to 0.08 mg/L. The Aquatic Life Use is assessed as impaired for Bound Brook based on the barrier to anadromous fish migration. Cabomba caroliniana is also a threat to this brook but was not observed at any of the downstream road crossings (DeCesare 2005). The low DO/saturation and pH, alkalinity, hardness conditions are considered to be naturally occurring as a result of the large upstream wetland areas. Primary and Secondary Contact RECREATION and aestheticsIn 2001 DWM conducted bacteria sampling at one station (AR101) on Aaron River upstream from the flow control structure at Beechwood Street, Cohasset, on three occasions during the primary contact season and on one additional date, 24 October 2001 (Appendix A). Samples were analyzed for fecal coliform, E. coli and Enterococcus sp. None of the fecal coliform bacteria counts exceeded 170 cfu/100 ml. Although DWM field survey crews noted no objectionable odors or oils, dense growths of aquatic vegetation and algal mats were observed in the brook upstream from the flow control structure throughout the summer of 2001 and more recently in the Hunters Pond impoundment (MassDEP 2001 and DeCesare 2005). During one sampling occasion after significant rain in 2001, the water was described as being brownish and very turbid although usually the water was slightly tea-stained and slightly turbid. The water column was again found to be highly turbid following a period of dry weather conditions along the entire segment of Bound Brook during a recent field reconnaissance visit (DeCesare 2005) The Recreational and Aesthetics uses are assessed as impaired for Bound Brook based primarily on the objectionable turbidity. These conditions were associated with both wet and dry weather conditions. The presence of algal mats frequently noted near the flow control structure and in the impounded reach of the river in Hunters Pond. The potential for Cabomba infestation is also of concern. Bound Brook (MA94-18) Use Summary Table
Directory: eea -> docs -> dep -> water -> resources -> 71wqar09 dep -> Charles D. Baker Governor dep -> Charles D. Baker Governor dep -> Charles D. Baker Governor dep -> Index of Photographs dep -> Department of environmental protection one winter street, boston, ma 02108 617-292-5500 water -> Water Resource Management Planning 71wqar09 -> 2004 water quality assessment report Download 3.32 Mb. Share with your friends:
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