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DEM Home > Programs > Bureau of Environ. Prot. > Office of Water Res. > Permits > RIPDES > Stormwater Program

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RIPDES Stormwater Program

Background and Regulatory Authority

In an effort to preserve, protect, and improve the nation's water resources from polluted stormwater runoff, the US Environmental Protection Agency (EPA) developed a Stormwater Program as required by the Clean Water Act (CWA). Implementation of Phase I of this program began in 1992. Phase II of the National Pollutant Discharge Elimination System (NPDES) Stormwater Program was finalized on December 8, 1999.

Combined Phase I and Phase II regulate stormwater discharges from three potential sources: municipal separate storm sewer systems (MS4s), construction activities, and industrial activities. Operators of many of these sources may be required to receive a NPDES permit before they can discharge. This permitting mechanism is designed to prevent and minimize stormwater runoff from washing harmful pollutants into local surface waters such as streams, rivers, lakes or coastal waters.

Since 1984, the Department of Environmental Management Rhode Island Pollutant Discharge Elimination System Program (RIPDES) has been the delegated authority to implement the NPDES program in Rhode Island. In 1993 RIPDES issued the first construction and industrial stormwater general permits for the authorization of stormwater discharges from construction activities disturbing greater than or equal to 5 acres and eleven categories of industrial activities. The RIPDES Regulations were amended to include the Phase II stormwater requirements on February 5, 2003. In 2003, RIPDES issued the first small MS4 general permit for authorization of stormwater discharges from regulated small MS4s.

Who Needs a RIPDES Permit?

The RIPDES Stormwater Program regulates the following types of stormwater discharges:

  Related Links

RIDEM Coordinated Stormwater Permitting

RI Stormwater Design and Installation Standards Manual

RI Soil Erosion and Sediment Control Handbook

RIDEM - Maps

RIDEM - Water Quality

RIDEM - TMDL Program

RIPDES Regulations (Amended: 2/5/03, eff.: 2/25/03)

RIPDES Permitting Program (Non-Stormwater)

For General Information 222-6800 • After Hours Emergencies 222-3070 • Disclaimer
rev. 5/5/14