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WMA water withdrawal Summary (APPENDIX E, TABLE E5)
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- NPDES wastewater discharge summary (APPENDIX E, TABLE E1)
- Use Assessment
- Biology
- Shellfish Harvesting
- Primary and Secondary Contact RECREATION and aesthetics
WMA water withdrawal Summary (APPENDIX E, TABLE E5)
*System-wide withdrawal, all sources are not necessarily within this segment. Additionally, there are 48 acres of cranberry bog open space in this subwatershed, inclusive but not limited to WMA registered growers (UMass Amherst 1999). For the purpose of this report, a conservative estimate of water use for this bog area is approximately 0.43 MGD. NPDES wastewater discharge summary (APPENDIX E, TABLE E1)The Scituate Water Department was authorized (MAG640042) to discharge from their water treatment plant, however no discharge has been occurring (wastewater is collected and taken off-site to wastewater treatment plant) and EPA terminated the permit in 2003. The area is currently being sewered so the lagoons will soon be abandoned and replaced with tanks with flow equalization, which will be tied into the WWTP (Keohane 2005a). The Town of Scituate is authorized (MA0102695 issued in November 2004 but currently under appeal) to discharge from the Scituate Wastewater Treatment Plant (WWTP) (formerly improperly permitted as a groundwater discharge) 1.6 MGD (average monthly) of treated effluent disinfected using UV light via Outfall #001 to a tidal creek tributary that flows into the Herring River. In 2000 the Town of Scituate’s WWTP was upgraded. This extended aeration facility performs nitrification for ammonia-nitrogen reduction and denitrification for total nitrogen reduction. Submerged anaerobic deep bed filters with methanol addition accomplish the denitrification process (Rowland 2004). The new total nitrogen limit (monthly average) is 4.0 mg/l using a 12-month moving average. The ammonia-nitrogen concentrations in the effluent between February 2000 and August 2004 ranged from <0.10 to 3.1 mg/L (n=19)(TOXTD database). The pH (permit limits 6.5 to 8.5 SU) of the effluent between February 2000 and August 2004 ranged from 6.3 to 7.6 SU (n=20) (only one measurement was < 6.5 SU). Since August 2000 the TRC measurements were all <0.05 mg/L (n=16)(TOXTD database). The facility’s whole effluent toxicity testing limits are LC50 >100 and C-NOEC >100% effluent (although the prior permit required monitoring only for chronic toxicity) using Mysidopsis bahia (acute testing) and Menedia beryllina (modified acute and chronic testing) on a quarterly basis. otherAccording to the Water Quality Certification variance, stormwater runoff from the Greenbush Commuter Rail Restoration Project will be directed to the Herring River from the train layover facility and parking facility at the Greenbush railroad station. Street sweeping, deep-sump hooded catch basins and the Downstream Defenders treatment units are proposed for water quality treatment (MassDEP 2004b). Water quality in the Old Stockbridge Grist Mill channel that drains into the Herring River appears to be compromised by unknown dry weather discharges as well as a lack of flow (stagnation) (Chase in preparation). Use AssessmentAquatic LifeHabitat and FlowSmelt spawning habitat in the Herring River includes the area downstream from the Old Oaken Bucket Pond dam to the tidal zone upstream from the New Driftway bridge (approximately 190m). Although the primary spawning riffle has very good physical features to support high densities of smelt eggs, several stressors that affect the smelt spawning habitat were identified by DMF biologists. These included low flows, algal growth that may also be exacerbated by flow manipulation, and the disturbed riparian buffer zone adjacent to the smelt spawning habitat (Chase in preparation). BiologyThe once numerous alewife run has apparently declined to low levels (Chase in preparation). ToxicityEffluent A total of 17 whole effluent toxicity tests were conducted on the Scituate WWTP effluent (Outfall #001) between February 2000 and August 2004. The LC50s were all >100% effluent for both test species with the exception of one M. bahia test (May 2000, LC50 = 91.4% effluent). The C-NOEC M. beryllina results ranged from <6.25 to 100% (n=16 valid tests) although the C-NOEC was 100% in 12 of these test events. Prior to November 2004 the facility was only required to monitor for chronic toxicity so there were no violations of the permit. During that time period, three tests that exhibited chronic toxicity did not exhibit a good dose-response relationship. Growth was significantly different in only the 6.25% test concentration in two tests (March 2001 and May 2002) while in the August 2004 test the CNOEC was 25% because of increased growth of the test organisms. The CNOEC of the November 2002 test was 50% effluent. No in-stream water quality data are available so the Aquatic Life Use is not assessed for the Herring River. This use is identified with an Alert Status, however, because of low flows, algal growth that may also be exacerbated by flow manipulation, the disturbed riparian buffer zone adjacent to the smelt spawning habitat and the apparent decline of the once numerous alewife run. Shellfish HarvestingThe DMF Shellfish Status Report of July 2000 indicates that Area MB5.3 (which contains this entire segment) is prohibited (MA DFG 2000 and Appendix G, Table G3). Based on the DMF shellfish growing area status, the Shellfish Harvesting Use is assessed as impaired because of elevated bacteria counts. The sources include the WWTP discharge although the marina and stormwater may also contribute to the bacteria problem. Primary and Secondary Contact RECREATION and aestheticsAlthough no quality assured data are available, it should be noted that since 1994 NSRWA volunteers have conducted bacteria sampling as part of their River Watch Monitoring Program on a weekly basis during the summer months. They sample at the James Landing Marina, Scituate along this segment of the Herring River (NSRWA 2005b). No objectionable conditions have been observed by DWM biologists in the Herring River (DeCesare 2005). The Primary and Secondary Contact Recreational are not assessed for the Herring River, however, the Aesthetics Use is assessed as support based on the lack of aesthetically objectionable conditions. Herring River (MA94-07) Use Summary Table
*Alert Status issues identified, see details in use assessment 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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