What is Stormwater?

  • Stormwater runoff is precipitation (rain or snow melt) that flows over land.
  • Storm drains collect runoff and convey it without treatment directly into water bodies. Polluted runoff affects drinking water, human health, wildlife, and property values. 
  • This infrastructure provides drainage that protects roads and the built environment from failure and flooding.
  • Adequately sized drainage systems are a critical utility for new development and urban expansion.

What is an MS4?

MUNICIPAL SEPARATE STORM SEWER SYSTEM, or MS4, means a stormwater conveyance that is separated from sanitary sewer systems.  The storm sewer system includes roads, curbs and gutters, ditches, catch basins, storm drains, outfalls, and pipes connecting these features.

York is subject to a CLEAN WATER ACT PERMIT, administered by the Maine Department of Environmental Protection (DEP), that allows the Town to discharge runoff into waterbodies is measures are taken to minimize pollution from the storm sewer system and municipal facilities and operations.  This permit is referred to as the MS4 General Permit.