In 1987, the EPA amended the Clean Water Act to require a two-phased national program to address water pollution from stormwater. Under the program, operators of municipal separate storm sewer systems (MS4) are required to obtain a National Pollutant Discharge Elimination System (NPDES) permit for the drainage system.
Phase I addressed stormwater discharges from medium and large MS4s (in cities with populations exceeding 100,000), construction sites greater than five acres, and several categories of industrial activities.
The Phase II stormwater program was published in the federal register on December 8, 1999. Phase II regulations require operators of small MS4s that serve populations of fewer than 100,000 people and are located in urbanized areas to obtain a NPDES permit. Operators of construction sites that disturb one to five acres of land are also required to obtain a NPDES permit.
Under the Phase II Stormwater Program, the city was required to submit a Notice-of-Intent (NOI) to discuss its Stormwater Management Program and Best Management Practices for the stormwater system. The city submitted this NOI in July 2003. The NOI serves as the basis for the city’s five year General Stormwater Permit. The EPA approved the NOI and issued the General Permit on September 26, 2003 which is renewed every five years.
Woburn is also required under the permit to provide annual reports on its progress on implementing its stormwater management program.