The storm drain or MS4 collects rainwater and discharged it directly to a creek or other water body without any treatment. The MS4 can consist of the street, curb and gutter, inlets to an underground piping or culverts that lead to a concrete lined ditch or creek. A discharge to the sanitary sewer goes into the completely separate sanitary sewer collection system, then to a treatment facility where it is cleaned to rigid permit requirements before it is either reused in the recycle water system or released to the environment.

Every facility that discharges wastewater are regulated and must be permitted. Read more on Industrial Wastewater and Stormwater Regulations from Texas Commission on Environmental Quality (TCEQ).


In order to protect the biological treatment of wastewater at the POTW, there are specific criteria and local limits for certain parameters. In addition there are a number of items that are completely prohibited from being introduced into the sanitary sewer system. If your facility discharges more than 25,000 gallons per day of process wastewater or is a “categorical” facility as identified by EPA then you may require a permit to discharge to SAWS.

  • Discharges from fire fighting activities and uncontaminated fire hydrant flushing (excluding discharges of hyperchlorinated water, unless the water is first dechlorinated and discharges are not expected to adversely affect aquatic life; uncontaminated fire hydrant flushing include flushing from systems which utilize potable water, surface water, or groundwater that does not contain additional pollutants; uncontaminated fire hydrant flushing do not include systems utilizing wastewater as source water);
  • Potable water sources (excluding discharges of hyperchlorinated water, unless the water is first dechlorinated and discharges are not expected to adversely affect aquatic life);
  • Lawn watering and similar irrigation drainage;
  • Water from the routine external washing of buildings, conducted without the use of detergents or other chemicals;
  • Water from the routine washing of pavement conducted without the use of detergents or other chemicals and where spills or leaks of toxic or hazardous materials have not occurred (unless all spilled material has been removed);
  • Uncontaminated air conditioner condensate, compressor condensate, and steam condensate;
  • Water from foundation or footing drains where flows are not contaminated with pollutants (e.g., process materials, solvents, and other pollutants);
  • Springs and other uncontaminated ground water;
  • It shall be a violation for any person to deposit, throw, drain, discharge, cause or allow to be deposited, thrown, drained or discharged, or otherwise cause to be injected into the MS4, or any storm sewer manhole, catch basin, private drain, ditch, street, gutter, creek, stream, tributary, or any other drainage device which connects with or drains into the MS4, any of the following described materials or substances within the corporate limits of the City of San Antonio:
    1. Any acid waste materials;
    2. Any alkaline waste materials;
    3. Any water or waste containing free-floating, or insoluble oil;
    4. Any gasoline, naphtha, fuel oil, mineral oil or other flammable or explosive liquid, solid or gas;
    5. Any noxious, malodorous, poisonous, or reactive substance which, either singularly or by interaction with other substances, or by its accumulation in the MS4 becomes injurious or potentially injurious to human, plant or animal life, or property; or
    6. Any domestic wastewater or industrial wastewater as defined in Article V, Division 3 of this chapter.
      It shall be a defense to prosecution under this section that such person was authorized to commit any act under a valid permit from the TCEQ or the United States Environmental Protection Agency
  • Prohibited Discharges into the Municipal Separate Storm Sewer System– Chapter 34, Article VI, Division 5
  • Industrial Waste – Sanitary Sewer – Chapter 34, Article V, Division 3

The North American Industry Classification System (NAICS) is a comprehensive demand-oriented product classification system to complement the new supply-oriented industry classification system of Canada, Mexico, and the United States. The Standard Industrial Classification (SIC) has been replaced by the new North American Industry Classification System (NAICS), but several data sets are still available with SIC-based data. Both SIC and NAICS classify establishments by their primary type of activity.

  • EPA Region 6 assistance
  • Used Automotive Parts Recyclers and Metal Recycling Requirements: Chapter 16 License and Business requires those business to apply for an annual license to operate.
    • Application for Business License shall include a copy of a current TPDES MSGP and a letter of compliance issued from SAWS within the last 15 months.
    • Section 16-197 Motor vehicle crushing shall only be performed in compliance with TCEQ and SAWS requirements to prevent the discharge of automobile fluids that could impact storm water discharges as outlined in the SWP3.
  • This state program is for issuing, amending, terminating, monitoring, and enforcing permits, and imposing and enforcing pretreatment requirements under Clean Water Act and the Texas Water Code and Texas Administrative Code regulations.
  • Pressure washers conducting business within the jurisdiction of the San Antonio Water System are eligible to join the San Antonio Water System Power Wash Program. For registration and registered Power Washers, visit SAWS Power Washing.
  • GPS coordinates for your location can be determined by using free web mapping sites such as Google Maps and Bing Maps.