EPA Region 1 has extended the deadline for the submission of comments to February 21, 2015 in response to the Draft General Permit for Stormwater Discharges from Small Municipal Separate Storm Sewer Systems in Massachusetts (known as MS4 systems). The 2003 MS4 General Permit, issued under the National Pollutant Discharge Elimination System (“NPDES”) program, expired in 2008 and has been administratively extended.
The new Draft General Permit was issued September 30, 2014, after the issuance of two Draft General Permits in 2010 for particular geographic areas: the North Coastal Draft Permit and the Interstate, Merrimack and South Coastal Draft Permit. Following comments and public hearings, EPA decided to issue a new Draft Permit that, among other things, combines these two permits into a single Draft Permit. The new draft permit and associated documents can be found here on the EPA Region 1 web site.
The MS4 General Permit covers small storm water systems operated by municipalities and cities located in urbanized areas. A map showing the urban areas covered by the MS4 program following the 2010 Census is located on the EPA Region 1 web site.
Although the application for coverage and reporting requirements are similar to the 2003 MS4 General Permit, the new Draft Permit imposes six minimum control measures on MS4 systems that, if implemented, are presumed, absent evidence to the contrary, to not require more stringent limitations to meet water quality standards. However, the most significant change is the proposed implementation of Water Quality Based Effluent Limitations (WQBELs) for specific MS4 communities to address Total Maximum Daily Loads (TMDLs) and Water Quality Limited Waters beyond these six requirements.
Under the draft permit, communities ranging from Ashland and Mendon to Cambridge and Somerville to Dover and Sherborn will need to develop and implement phased plans over the next 20 years to address phosphorus in the Charles River Watershed. Other communities (Auburn, Charlton, Dudley, Gardner, Grafton, Granby, Hadley, Harvard, Hudson, Leicester, Ludlow, Millbury, Oxford, Shrewsbury, Spencer, Springfield, Stow, Templeton, Wilbraham, and Winchendon) will need to develop plans to reduce phosphorus in lakes and ponds by as much as 65 percent. Other WQBEL requirements target bacteria and pathogen TMDL requirements in scores of municipalities, nitrogen loading in the watersheds, ponds, and bays of Cape Cod, and phosphorus TMDLs in the Assabet River.
The Draft Permit also proposes to regulate discharges in Massachusetts to water bodies that are tributary to out-of-state water bodies with TMDLs, including Long Island Sound (nitrogen) and certain Rhode Island waterbodies (phosphorus, bacteria, pathogen, and metals). The WQBEL requirements are detailed in Appendix F of the Draft Permit.