Ohio Stormwater-Municipalities regulations & environmental compliance analysis

Ohio Stormwater-Municipalities: What you need to know

Governing Law and Regulations

National Pollutant Discharge Elimination System (NPDES) Permits: Ohio Administrative Code (OAC) 3745-38-01 to 3745-38-12

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Municipal separate storm sewer systems (MS4s):

Small MS4s: OAC 3745-39-03

Large and medium MS4s: OAC 3745-39-04

Regulatory Agencies

Ohio Environmental Protection Agency (OEPA) Division of Surface Water

U.S. Environmental Protection Agency (EPA) Region 5

See ADDRESSES & CONTACTS for addresses and telephone numbers.

See national section for basic information and federal regulations.

Comparison: State vs. Federal

Rules. Ohio has been delegated authority to administer the National Pollutant Discharge Elimination System (NPDES) permit program for wastewater discharges, including permit authority for stormwater discharges associated with municipal separate storm sewer systems (MS4s), by the U.S. Environmental Protection Agency (EPA). The state issues both general and individual permits to MS4s. See the national section STORMWATER— MUNICIPALITIES for more information on the federal MS4 permitting program.

Administration and enforcement. OEPA's Division of Surface Water is responsible for the administration and enforcement of the stormwater discharge permit regulations in Ohio.

State Requirements


Ohio issues a general permit that authorizes discharges of stormwater from a select group of small MS4s that serve populations less than 100,000 in urbanized areas, and those that have or may have the potential to negatively impact surface water quality as a result of their discharges. An MS4 individual permitting program exists for those serving populations of more than 100,000.

Small MS4s

OAC 3745-39-03

The small MS4 general permit (OHQ000003) authorizes discharges of stormwater ...

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