Stormwater Quality

Stormwater is the liquid precipitation that is the result of a rain event. Once the stormwater reaches the ground a portion of stormwater will evaporate back into the atmosphere, a portion will soak into the soil and regenerate groundwater, and the rest of the water will flow along the ground becoming stormwater runoff.

StormDrain

Is stormwater runoff bad for the environment?

In a pristine untouched area, a stormwater runoff would have virtually no negative impacts on the surrounding environment. In the world we live in today, stormwater runoff has become a transporter of pollution and can have lasting negative effects on the environment. As cities grow and more areas are covered with impervious surfaces less rainwater is absorbed into the ground and more stormwater runoff is generated. This runoff carries contaminants to our storm drains and directly into lakes and streams.

Local Stormwater Pollution

Unlike the water that goes down your sink or bathtub, which drains to the sewer collection systems, water that flows into storm drains is not treated and filtered for pollutants. This contaminated water then flows directly into drainage ditches and lakes that feed into Oyster Creek and the Brazos River. From there the pollutants flow south into the Gulf of Mexico.

Letting pollutants reach your storm drains is like contaminating your own food source. Anything other than pure rainwater is a potential contaminant that degrades water quality and aquatic life.

Types of Stormwater Pollution

It's very important that you help prevent contaminants from flowing into storm drains and never pour anything into them. Intentionally pouring pollutants into street gutters and storm drains is dangerous to the environment and is also considered an illicit discharge.

Illicit Discharge

Illicit discharge means any discharge into a municipal separate storm sewer system (MS4) that is not entirely composed of stormwater, except for discharges allowed under the Texas Pollutant Discharge Elimination System (TPDES).

Prohibited Discharges

Allowed Discharges

Chlorinated pool waterIndividual residential car wash water
Commercial car wash wastewaterDechlorinated pool water
Used oil, lubricants, or petroleum productsUncontaminated groundwater
Sanitary sewer overflowRunoff from landscape irrigation 
Leakage from dumpsters or trash containersWater utility line flushing
Vehicle fluidsStreet wash water excluding street sweeper wastewater
Construction debris (paint, dirt, concrete rinses)Flows from emergency fire fighting activities
Water containing detergents or cleaning chemicals from pressure washingAir conditioning condensation
Food and kitchen cleaning water from food service facilitiesDischarge from other potable water sources
Water softener brine or backwash

Report Stormwater Pollution

To report any stormwater issues, submit a ticket or contact 311


  1. What is stormwater runoff?
  2. Why is stormwater runoff a problem?
  3. Where does my stormwater go?
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