Stormwater Management / Plymouth, Indiana

What is Stormwater?

Stormwater is any precipitation that comes from rain, snow, and ice melt and stormwater runoff results from the water that does not infiltrate into the ground, evaporate, or recharge rivers and lakes. Stormwater can flow off building rooftops, driveways, lawns, streets, parking lots, construction sites, and industrial storage yards. There is a stormwater system in place consisting of storm drains, pipes, and outfalls that are designed to carry rainwater away to prevent flooding. As it flows through the storm drain, stormwater picks up pollutants, trash, and debris. These types of pollutants can harm fish and wildlife populations, kill native vegetation, foul drinking water supplies, and make recreational areas unsafe and unpleasant. It is in the interest of every community to manage its stormwater runoff to protect its residents' health, welfare, and safety and preserve the natural resources.

Quality of Stormwater Runoff

Indiana's MS4 Program provides a positive water quality impact in our streams, rivers, and lakes. The MS4 Program is an unfunded mandate by the United States Environmental Protection Agency (EPA) and the Indiana Department of Environmental Management (IDEM) as part of the Phase II National Pollutant Discharge Elimination System (NPDES).

Report an Illicit Discharge

The City of Plymouth is committed to keeping our storm water clean and free of pollutants. As part of that effort, we ask that if you see something that could potentially cause a pollution issue, please email us at stormwater@plymouthin.com.

Construction Stormwater Management

As of December 18, 2021, Indiana no longer administers the construction stormwater program under Indiana Administrative Code (327 IAC 15-5 or Rule 5). Permitting coverage is now issued under the Construction Stormwater General Permit (CSGP). The CSGP is a performance-based regulation designed to reduce pollutants that are associated with construction and/or land-disturbing activities.

Helpful Links:

Stormwater Tip Sheets:

Stormwater Tip Sheet for Business: Auto Shops (pdf)

Stormwater Tip Sheet for Business: Auto Shops (Spanish) (pdf)

Stormwater Tip Sheet for Business: Construction Crews (pdf)

Stormwater Tip Sheet for Business: Construction Crews (Spanish) (pdf)

Stormwater Tip Sheet for Business: Construction for Consumers (pdf)

Stormwater Tip Sheet for Business: Construction for Consumers (Spanish) (pdf)

Stormwater Tip Sheet for Business: Lawn Care (pdf)

Stormwater Tip Sheet for Business: Lawn Care (Spanish) (pdf)

Stormwater Tip Sheet for Business: Parking Lots (pdf)

Stormwater Tip Sheet for Business: Parking Lots (Spanish) (pdf)