Stormwater (MS4) Overview

Stormwater managementis a non traditional component of the town of Barnstable’s Comprehensive Wastewater Management Plan.

Sometimes referred to as MS4, stormwater management plays a prominent role in several watersheds and our ponds and lakes.  



What is considered stormwater?

Any precipitation that falls from the sky, including rain, hail, and snow, is considered stormwater. In a natural landscape without development, stormwater is absorbed into the ground or falls into bodies of water. This gives needed water to plants and animals and replenishes reserves of surface and groundwater.

What is stormwater management?

Stormwater management is the effort to reduce runoff of rainwater or melted snow into streets, lawns and other sites and the improvement of water quality, according to the United States Environmental Protection Agency (EPA)

What is a stormwater MS4?

Polluted stormwater runoff is commonly transported through municipal separate storm sewer systems (MS4s), and then often discharged, untreated, into local water bodies.

An MS4 is a conveyance or system of conveyances that is:
  • owned by a state, city, town, village, or other public entity that discharges to waters of the U.S.,
  • designed or used to collect or convey stormwater (e.g., storm drains, pipes, ditches),
  • not a combined sewer, and
  • not part of a sewage treatment plant, or publicly owned treatment works (POTW).

Glossary of Terms

Stormwater (noun): Stormwater, also written storm water, is water that originates from precipitation (storm), including heavy rain and meltwater from hail and snow.

Common Stormwater Pollutants: sediment, fertilizers, bacteria from pet and wildlife waste, automobile fluids, heavy metals, pesticides, and herbicides.