Welcome to the GCSA Website Home Page  

Public Information and Resources

Stormwater Permitees
Information and Resources


Here you will find information for businesses and the general public, as well as technical resources for stormwater permittees. If you have questions about a specific city or county, contact the local stormwater staff listed in the GCSA Partner Communities webpage or contact INCOG’s stormwater coordinator by email at stormwater@incog.org or phone 918.584.7526.

BLUE PAGES – are for citizens, industries and organizations to obtain technical and policy information about complying with the stormwater permit program.

YELLOW PAGES – are for stormwater permittees to obtain technical support to help with their permit compliance and program implementation.

Water Quality, Not Flood Control – The EPA stormwater permit program is about controlling pollution, not about controlling flooding.

Untreated Rainfall Runoff – In Oklahoma, stormwater runoff does not flow to any type of pollution treatment system, it flows untreated to streams, ponds and lakes.

Wide Spectrum of Urban Pollutants – everything from bacteria to sediment, nutrients to metals, pesticides and other toxics can be found in stormwater runoff.

Permitting Authorities – The federal Environmental Protection Agency (EPA) delegated its stormwater permitting authority to the Oklahoma Department of Environmental Quality (ODEQ), but EPA continues to have final oversight.

General Permits – Oklahoma uses three: OKR05 for industrial activities, OKR10 for construction activities, and OKR04 for small municipal stormwater permittees. Coverage under each is obtained by submitting an application called a Notice of Intent (NOI), and preparing a Stormwater Pollution Prevention Plan (SWP3) for OKR10 and OKR05 coverage, and a Stormwater Management Program (SWMP) document for OKR04 coverage.

Important Acronyms – MS4 “Municipal Separate Storm Sewer System” is the city or county owned stormwater collection system that includes streets, gutters and ditches. BMP “Best Management Practice” is an action or structure used to help reduce stormwater pollution, including public education events, volunteer monitoring, and construction inspections. LID “Low Impact Development” is an action or structure that deals with the reduction of rainfall runoff and pollutants; LID examples are rain gardens and pervious concrete.

How can rain cause pollution? Rainfall in urban areas carries with it loose material and chemicals that can cause pollution in local ponds and streams. Pollutants in rainfall runoff flow to the stormwater collection system (storm sewer system) and ultimately get discharged directly into local rivers and streams without treatment. Common pollutants in stormwater runoff include trash, solvents, petroleum products, heavy metals, pesticides, fertilizers, bacteria, and sediment and chemicals from construction sites.

The U.S. Environmental Protection Agency (EPA) regulates stormwater discharges from many of Oklahoma’s Municipal Separate Storm Sewer Systems (MS4s). The 1990 Phase I regulations addressed large cities (Tulsa and Oklahoma City) and 11 categories of "industrial activities". The 1999 Phase II regulations addressed many other cities in Oklahoma. The Oklahoma Department of Environmental Quality (ODEQ) is the permitting authority in Oklahoma for urban MS4s. Also included in EPA’s stormwater permit coverage is any construction activity that has 1 acre or more of disturbance.

Many of INCOG’s city and county members, including additional cities in Oklahoma, have created the Green Country Stormwater Alliance (GCSA) to collectively address stormwater pollution regionally. INCOG coordinates all GCSA activities, which include a variety of public education programs, technical assistance, and employee training. This website is dedicated to assistance for citizens and businesses within the GCSA, as well as for providing resources for GCSA municipalities themselves.

GCSA Internet Resources
GCSA Education Materials
Acronyms for Stormwater (pdf)
GCSA Members
OSU’s Low Impact Development (LID)


Section 303(d) of the Clean Water Act requires each state to publish a list of impaired waterbodies every two years (biennially). Impaired waterbodies are now referred to as “Category 5” in the State’s biennial Water Quality Assessment Integrated Report. The latest version approved by EPA is available online at this ODEQ website. Visit the GCSA Water Quality in NE Oklahoma webpage for a map of impaired streams in the Tulsa area. Visit the ODEQ’s Water Quality Division website for more information about stream impairment and other ODEQ regulatory programs in Oklahoma. All impaired streams that remain on the Category 5 list will likely have a Total Maximum Daily Load (TMDL) study. The TMDL will set load limits on all point source dischargers and significant non-point sources so that water quality standards will be met. There are many streams in the Tulsa area that will have a TMDL performed over the next 10 years.

The ODEQ has begun the process of renewing the State’s Stormwater General Permit for Small MS4s (OKR04). This is the permit under which all GCSA members are permitted. The renewal of OKR04 will be finalized in 2014. It will likely include additional requirements for Low Impact Development (LID), additional requirements for 303(d) impaired waterbodies, and new requirements to address protected aquatic species and their critical habitat. ODEQ publishes copies of its stormwater general permits on their ODEQ stormwater website.