Stormwater Management Program

Management Program Questionnaire

Please take a moment to fill out the city's Stormwater Management Program questionnaire.

On Aug. 13, 2007, the Texas Commission on Environmental Quality (TCEQ) issued the Small Municipal Separate Storm Sewer Systems (MS4) Permit authorizing storm water and certain non-storm water discharges to the city’s MS4. This affects cities with populations under 100,000 (according to the 1990 Census Bureau). Cities with populations over 100,000, such as Arlington, Dallas and Fort Worth came under Phase I rules and already have storm water programs in place.

The City of Grand Prairie submitted to the TCEQ a Notice of Intent (NOI) requesting coverage under this permit and a Storm Water Management Program (SWMP) that outlined the city’s proposed Minimum Control Measures (MCM) as follows: 1) Public Education and Outreach on Storm Water Impacts, 2) Public Involvement and Participation, 3) Illicit Discharge Detection and Elimination, 4) Construction Site Storm Water Runoff Control, 5) Post-Construction Storm Water Management, and 6) Pollution Prevention and Good Housekeeping. Each of these MCMs lists specific Best Management Practices developed to reduce storm water pollutants discharged to the city’s MS4. This is great news for the citizens and visitors of Grand Prairie and for the environment!

The TCEQ accepted the city's NOI and SWMP, and has authorized the city to discharge stormwater associated with the Small MS4 under the terms and conditions set forth in the permit.

The TCEQ reissued the MS4 permit in January of 2019. The City revised the SWMP according to the new permit and, in July 2019, resubmitted the NOI and SWMP for approval.

What is a small MS4?

A small MS4 is defined as a conveyance or system of conveyances (including streets, curbs, gutters, ditches, storm drains, etc.) that is owned by a city having jurisdiction over disposal of sewage, storm water, or other wastes, designed or used for collecting or conveying storm water, that is not a combined sewer, and that was not previously categorized as a medium or large MS4.

Why have cities implemented these programs?

Storm water quality management programs are a response to regulations from the Environmental Protection Agency (EPA) connected to the federal Clean Water Act. These regulations require cities to obtain a permit under the National Pollutant Discharge Elimination System, or in Texas’ case the Texas Pollutant Discharge Elimination System, and to create a comprehensive program to seek out and eliminate, to the maximum extent practical, pollutants carried by storm water.


In 1972, Congress amended the Federal Water Pollution Control Act (commonly referred to as the Clean Water Act (CWA)) which prohibited the discharge of any pollutant to waters of the United States from a "point source" unless the discharge is authorized by a National Pollutant Discharge Elimination System permit. A "point source" is a single identifiable localized source of pollution such as an industry, business or a sewer system.

In 1987, the CWA was amended and established a $400 million program for States to develop and implement, on a watershed basis, nonpoint source management, because water quality studies showed sparse sources of water pollution were also significant causes of pollution. They called these sparse sources of pollutants a "nonpoint source.” A "nonpoint source" pollution is water pollution that is difficult to trace to a specific discharge point because it comes from many sources. Examples of common nonpoint source pollutants include fertilizers, pesticides, sediments, oils, salts, trace metals, and litter. Nonpoint sources come from locations such as farms, yards, roofs, construction sites, automobiles and streets.

Phase I of the U.S. Environmental Protection Agency’s (EPA) storm water program was promulgated in 1990 under the CWA. Phase I relies on National Pollutant Discharge Elimination System (NPDES) permit coverage to address storm water runoff from: (1) “medium” and “large” municipal separate storm sewer systems (MS4s) generally serving populations of 100,000 or greater, (2) construction activity disturbing 5 acres of land or greater, and (3) ten categories of industrial activity. On Sept. 17, 1998, control over storm water permitting shifted from EPA’s National Pollutant Discharge Elimination System (NPDES) program to Texas’ version, the Texas Pollutant Discharge Elimination System (TPDES).

Phase II rules for small municipalities and construction activity were finalized in December 1999. The TCEQ issued the Phase II MS4 Permit on Aug. 13, 2007, to small municipalities with residential populations under 100,000 (according to the 1990 Census Bureau). Phase II requires permit coverage for all small MS4s located within urbanized areas, where an urbanized area is defined by the U.S. Census Bureau as “a land area comprising one or more places — central place(s) — and the adjacent densely settled surrounding area — urban fringe — that together have a residential population of at least 50,000 and an overall population density of at least 1,000 people per square mile."

For more information about the City of Grand Prairie Storm Water Management Plan, please contact our Public Health and Environmental Quality Department at 972-237-8055.