Interlocal Stormwater Working Group

A coalition of fourteen municipalities and two nested MS4 communities in the Greater Portland and Saco areas working together to address stormwater pollutants.

The Interlocal Stormwater Working Group (ISWG, pronounced izzy-wig) consists of Biddeford, Cape Elizabeth, Cumberland, Cumberland County Soil & Water Conservation District, Falmouth, Freeport, Gorham, Old Orchard Beach, Portland, Saco, Scarborough, South Portland, Southern Maine Community College, University of Southern Maine, Westbrook, Windham, and Yarmouth. These communities work collaboratively to implement the Clean Water Act Municipal Separate Storm Sewer System (MS4) permit. The permit aims to reduce the impact of stormwater pollution on local waterways. In Maine, the Department of Environmental Protection administers this permit on behalf of the US Environmental Protection Agency.

The Cumberland County Soil & Water Conservation District coordinates ISWG and provides regional support and implementation of many of the permit’s six required minimum control measures (MCMs).