Stormwater

Overview
   Relevant Activities
   Role of Local Governments
U.S. EPA Resources
Other Resources 
   States
   Other Federal Agencies & Programs
   Associations for Local Officials
Funding & Financing


OverviewStormwater

When rainwater runs off the sides of buildings and over parking lots and other impervious urban areas, it picks up and transports pollutants. In times of heavy rainfall, sanitary sewer systems may not have the capacity to hold all the water entering the system, which results in sanitary sewer overflows (SSOs) and combined sewer overflows (CSOs). These events often result in the discharge of sewage and pollutants to nearby surface waters, which may violate state or federal law. However, many local governments lack the financial and technical resources necessary to address these issues. The resulting noncompliance with regulations designed to address wet weather pollution can further increase the burden on these local governments.

Relevant Activities

Role of Local Governments

Under the federal Clean Water Act, the National Pollutant Discharge Elimination System (NPDES) permit program controls water pollution by regulating sources of pollution that discharge into waters of the United States. Under the NPDES stormwater program, operators of large, medium and regulated small municipal separate storm sewer systems (MS4s) require authorization to discharge pollutants. Phase I, promulgated in 1990, requires medium and large MS4 operators (those serving populations of 100,000 or more) to submit comprehensive permit applications for individual permits. Regulated small MS4 operators have the option of choosing to be covered by an individual permit, a general permit, or a modification of an existing Phase I MS4's individual permit.

Local governments involved in construction projects also need to comply with stormwater construction rules. Stormwater runoff from construction activities can have a significant impact on water quality by contributing sediment and other pollutants to creeks, streams, lakes, etc. Federal regulations relating to the NPDES Stormwater Permit Program require operators of certain sized construction projects to obtain authorization to discharge stormwater under a NPDES construction stormwater permit. The Phase II Stormwater regulations, which became effective March 2003, require construction activities that disturb one or more acres of land to obtain NPDES permit coverage.

Although stormwater regulations are federal rules, they are implemented by state environmental agencies (except for Massachusetts, New Mexico, Alaska, Idaho, and New Hampshire where EPA retains authority).

U.S. Environmental Protection Agency Resources

Other Resources

States

Other Federal Agencies & Programs

Associations for Local Officials

Funding & Financing

For more information on funding and financing programs and options for stormwater, please see the Wastewater and Stormwater section of LGEAN's Funding & Financing page.

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