Oklahoma DEQ Administers Statewide Stormwater NPDES Permits

Under the Oklahoma Pollutant Discharge Elimination System, codified at 27A O.S. Section 2-6-101 et seq., DEQ implements federal Clean Water Act stormwater requirements. Construction sites disturbing one acre or more must obtain coverage under DEQ's Construction General Permit and prepare a Stormwater Pollution Prevention Plan. Municipal Separate Storm Sewer Systems serving urbanized areas need Phase II MS4 permits. Industrial facilities in regulated sectors need Multi-Sector General Permit coverage. While cities may adopt drainage and erosion ordinances, stormwater discharge permitting itself is a state function and local rules cannot lower DEQ thresholds or substitute for state permits.

Discharging stormwater without required DEQ permit coverage exposes operators to civil penalties up to $10,000 per day per violation, plus mandatory cleanup orders and potential criminal liability for willful violations.