DEM hosts discussion of Ten Mile River in East Providence
EAST PROVIDENCE — The Department of Environmental Management will hold an informational meeting on Wednesday, Jan. 8, to discuss the draft water quality restoration plan for the Ten Mile River. The meeting will take place from 4 to 6 p.m. at the Weaver Library located at 41 Grove Ave. in East Providence.
The Ten Mile River and its impoundments, Central Pond, Turner Reservoir, and Omega Pond do not meet state water quality standards for total phosphorus, dissolved oxygen, pathogens, and the following metals: aluminum, cadmium, lead, and iron. These water quality impairments adversely affect both recreational use and aquatic life. As a result of the elevated phosphorus levels, the river and its impoundments frequently experience excessive growth of rooted aquatic plants and algae, low dissolved oxygen levels and cyanobacteria blooms. These nuisance conditions impact aquatic life, and in the case of cyanobacteria blooms, make the river unsafe for recreation.
Wastewater and stormwater discharges represent the two most significant sources of pollution to the river. The Ten Mile River is effluent dominated, meaning that a majority of the riverís flow during periods of no precipitation consists of treated wastewater discharged from two publicly-owned treatment works located in North Attleborough and Attleboro, Massachusetts. The watershed is also heavily urbanized with total coverage by impervious surfaces in the Massachusetts portion of the watershed at 20% and in Rhode Island at over 40%. Thus under rain and/or snowmelt events, urban runoff containing pathogens, metals, and phosphorus, flows largely untreated into the Ten Mile River ñ further degrading its water quality.
Other sources of pollutants to the Ten Mile River and its impoundments include: 1) nuisance populations of non-migratory geese and swans, 2) contaminated sediments re-introduced to the water column via scour of streambed and streambank during high flows, 3) contaminated groundwater, 4) phosphorus released from sediments in impounded portions of the river, and 5) natural sources that include native wildlife, forests and other undeveloped land, and atmospheric deposition. These source categories may intermittently contribute pollutants to the river system, but are not easily quantified.
The water quality restoration plan, prepared by RIDEMís Office of Water Resources, is consistent with federal Clean Water Act requirements and is formally called a Total Maximum Daily Load (TMDL). The TMDL details specific pollution abatement requirements and recommendations for pollution sources in RI including urban runoff, nuisance populations of waterfowl, and fertilizer and other chemical applications at golf courses. The cities of Pawtucket and East Providence, and the Rhode Island Department of Transportation (RIDOT) will be required to amend their Stormwater Management Program Plans consistent with the requirements described in the document.
For water quality objectives to be achieved, pollution reduction is also necessary in the Massachusettsí portion of the watershed. Towards that end, the TMDL establishes allowable pollutant loads at the northern MA/RI state line. The document does not specify how the needed pollutant reductions are to be achieved in Massachusetts, however, in re-issuing the two MA wastewater treatment facilitiesí NPDES permits, US EPA and MADEP must take into consideration the TMDLís findings.
Given that the Ten Mile River is a bi-state river system, RIDEM has sought to coordinate with MADEP and US EPA throughout the TMDL development process beginning with development and implementation of a watershed wide sampling plan in 2007 and 2008 (with technical support from US EPA). RIDEM has also coordinated with MADEP and US EPA counterparts on the overall technical approach for establishing allowable pollutant loads, and on development of pollution abatement recommendations.
The water quality restoration actions outlined in this TMDL complement the US Army Corps of Engineers' $4.8 million project to restore anadromous fish to the Ten Mile River by creating fish ladders at Omega Pond Dam, Hunt's Mill Dam and the dam at Turner Reservoir. Completion of all three fishways will allow alewives, blueback herring and American shad to reach their freshwater spawning habitats in the Ten Mile River up to the Golf Club Dam in Pawtucket. Restoring fish passage to the Ten Mile River provides significant benefits to the freshwater and estuarine ecosystems and to the surrounding communities. Improving the quality of these waters is an essential component of river restoration efforts.
The Executive Summary, which provides more detail on the TMDL document, is available online at RIDEMís website at http://www.dem.ri.gov/programs/benviron/water/quality/rest/reports.htm