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NPDES/MS4

NPDES/MS4

The NPDES permit program addresses water pollution by regulating point sources that discharge pollutants to waters of the United States.

Created in 1972 by the Clean Water Act, the NPDES permit program is authorized to state governments by EPA to perform many permitting, administrative, and enforcement aspects of the program.

The United States Environmental Protection Agency’s (EPA) National Pollutant Discharge Elimination System (NPDES) municipal stormwater program regulations were published in 1990. These regulations were implemented in two phases. In 1990, Phase I established requirements for stormwater discharges associated with 11 categories of industrial activity, and for large (population >250,000) and medium (population >100,000) municipal separate storm sewer systems (“MS4”). In Maryland, ten jurisdictions and the State Highway Administration (SHA) were required to apply for coverage under individual MS4 stormwater permits. More information concerning the Phase I permits may be found here: click here to learn more about the Phase I permits

Regional Stormwater Management

Environmental Management

16232 Elliott Parkway
Williamsport, MD 21795

Phone: (240) 313-2600
Fax: (240) 313-2601

Office Hours:  Monday – Friday, 7:30am to 4:00pm

TTY users may call any government office through the Maryland Relay Service 1-800-735-2258