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Questions or Comments: wqap@tceq.texas.gov

Stormwater Permitting Requirements for Phase II (Small) MS4s

Authorization options, control measures required, annual reporting requirements, and links to best management practices for operators of Phase II MS4s.

Stormwater Management Program

If you operate a regulated small municipal separate storm sewer system (MS4), then you must develop and submit to the TCEQ, a stormwater management program (SWMP) that includes at least these six minimum control measures (MCMs):

  • MCM 1: Public Education, Outreach, and Involvement

  • MCM 2: Illicit Discharge Detection and Elimination

  • MCM 3: Construction Site Stormwater Runoff Control

  • MCM 4: Post-construction Stormwater Management in New Development and Redevelopment

  • MCM 5: Pollution Prevention and Good Housekeeping for Municipal Operations

  • MCM 6: Industrial Stormwater Sources (only if your MS4 serves a population more than 100,000)

These minimum control measures must be developed by identifying and applying best management practices (BMPs). See the EPA’s “Menu of BMPs for examples and guidance. (Depending on the rainfall conditions and topography in your area, some of these BMPs might have to be adapted to your local situation.)

EPA's MS4 Permit Resources

On April 14, 2010, the U.S. EPA adopted the MS4 Permit Improvement Guide and during 2016 through 2017 EPA published five Compendiums with examples of MS4 permit requirements. The primary purpose of these guidance documents is to assist permit writers at EPA and the states in strengthening Phase I and Phase II MS4 permits.

During the renewal of each individual Phase I permit, as well as during the Phase II general permit (TXR040000) renewal, the TCEQ reviewed these documents and determined the extent to which the recommendations in these documents would be incorporated into the TPDES MS4 permits.

2019 Small MS4 General Permit Issued

The Small MS4 General Permit, TPDES Permit No. TXR040000, was issued on January 24, 2019. It authorizes the discharge of stormwater to surface water in the state from small municipal separate storm sewer systems (MS4s).

Please visit the General Permit TXR040000 for Phase II Small MS4s webpage for more information.

Annual Report

The MS4 operator will submit a concise annual report to TCEQ within 90 days of the end of each reporting year selected by the MS4 (permit year, calendar year, or fiscal year). The annual report must describe the activities conducted during the MS4’s reporting year and must be submitted even if the SWMP has not yet been approved by TCEQ. The annual report must be submitted on TCEQ Form 20561. For additional information see the Assistance Tools for Stormwater Permitting.

Shared Programs

If permittees are participating in a shared SWMP, then they must contribute to a system-wide annual report. Each permittee must sign the report, but only one report must be submitted.

The annual report must be submitted to the TCEQ’s Stormwater Team at the address below.

Stormwater Team Leader
TCEQ Water Quality Division
MC-148
P.O. Box 13087
Austin, Texas 78711-3087

In addition, a copy of the annual report must be submitted to the appropriate TCEQ regional office.

Contact us if you need more information about this general permit.