Storm Water Quality Management (SWQMP) in the City of Houston

November 1, 2017 by Shaun Theriot-Smith

Navigating storm water quality regulations in Houston can often be a nebulous process, especially when you are juggling other permitting requirements simultaneously. Let’s take a look at how storm water quality is managed and regulated by the City of Houston.

(This is the second post in a 2-part series. Read the first post here.)

Rainfall and its Impact

Storm Drain inletMunicipalities and counties in south Texas are quite concerned about what happens when it rains – and for good reason. Just take a look at the last major rain events we’ve had in the Houston metro area over the past few years. Hurricane Harvey as well as the Tax Day and Memorial Day floods in 2016 and 2015 have forced our public works advocates and property owners to reconsider the true impact of rain. Storm water is obviously a big deal in Houston and Harris County.

The City of Houston and Harris County hold a developer and their designers responsible for the stormwater that leaves a private site. These agencies are often primarily concerned with the quantity or volume of the stormwater discharge, but they also expect a certain quality or characteristic of the water that enters into the MS4, or municipal separate storm sewer system. Enter Storm Water Quality (SWQ) guidelines and the Storm Water Quality Management Plan (SWQMP).

Who needs a SWQ permit?

The SWQMP provides a post-construction narrative of storm water quality management for a your property. In real terms, it outlines the operation and maintenance of the long-term structural and non-structural BMPs that mitigate identified sources of pollution on the site during its typical operation and lifecycle. The SWQMP differs from the Storm Water Pollution Prevention Plan (SWPPP), which you can read about in our previous post.

While your development is in the permitting process at the City of Houston, you may need to also secure and continuously maintain a Storm Water Quality Permit for your property which authorizes the SWQMP on an annual basis. How can you determine whether your development will need a SWQ permit?

In the City of Houston, it’s simple — if you are developing a new property that is 5 acres or greater, or you are redeveloping an existing property that is greater than 5 acres and is modifying 1 acre or more, you will be required to produce a SWQMP and maintain a SWQ permit with the City of Houston. This permit must include an engineer’s certification and be renewed on an annual basis.

SWQ Flowchart

Industrial Activity Certification

If your development includes industrial equipment and material or may be classified as a high-risk commercial development, you may be required to follow additional storm water quality criteria and inspections as outlined in the in the City of Houston code of ordinances and as guided in the TPDES General Permit for Storm Water Discharges Associated with Industrial Activity.

Do you have Storm water quality questions specific to your development or need to fulfill SWQ permitting requirements? BIG RED DOG can help. Contact our experts in Houston at 832-730-1901 and we will walk you through the SWQ and SWQMP process.

This post is the first of a two-part series covering storm water quality management in the City of Houston and was originally published on Shaun Theriot-Smith’s blog. Read Part 1 here.

Photo Credit: s__i (cc)

Written by Shaun Theriot-Smith

Shaun Theriot-Smith

Shaun Theriot-Smith is a Project Engineer in our Houston office. Shaun graduated from The University of Houston with a Bachelor of Science in Civil Engineering. He enjoys spending time with his wife and twin daughters.