A person using a soapy cloth to wash a tire rim on the grass.

Detergents and Soaps

Make sure only rain goes down the drain

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Detergent At-home Tips Commercial Carwashes Practices for Professionals Carpet Cleaning


The detergent and other chemicals in car soap can pollute local waterways. This happens when soapy wash water enters a storm drain or stream when you're washing your car. You can help protect the environment by making sure this water does not go into the stormwater system.

At-home Tips

  • Keep water out of the street - Wash your car in the yard or on a gravel area.
  • Use half the amount of soap so that the detergent breaks down faster.
  • Direct wash water toward the lawn or a planted area.

Mobile Carwashes

  • Use cool water and biodegradable detergents.
  • Clean vehicles on grass or gravel areas (when possible).
  • Cover nearby storm drains before washing vehicles.
  • Don't do any engine or parts cleaning.
  • Avoid acid-based wheel cleaners.

Is a mobile carwash coming to your neighborhood? Let us know ahead of time. This will help prevent issues with wash water going into a storm drain. Call the main Stormwater Hotline at 919-996-3940.

Commercial Carwashes

  • Direct soapy water from the carwash to the sanitary sewer system. Don't put wash water in the stormwater system. 
  • If a sewer connection is not available – direct wash water to collection pools or a similar method. Dispose of wash water properly in a sink.
  • Let us know if you see a mobile carwash that isn’t properly disposing wash water. They should follow the same rules as commercial carwashes.

Practices for Professionals

Do you do sanitary sewer maintenance or sidewalk/concrete repair? Follow these tips to properly dispose of wash water so that it doesn't make its way into the stormwater system. You'll protect the health of the waterways and help us meet permit requirements.

  1. Don't use soaps or chemicals when pressure washing pavement.
  2. Sweep surfaces before pressure washing. 
  3. Keep wash water out of storm drains and waterways.
    • Collect all water and dispose of properly,i.e., in a sink or drain that connects to the sewer system.
    • If you cannot collect the water then use a drain seal, filter sock, or other method to either filter the water or redirect it away from a drain.
  4. When disposing of chemicals, follow the directions on the package or Materials Safety Data Sheet (MSDS).
  5. Carry spill response details with you. Contact us if you can't contain the spill at 919-996-3940 or RaleighStormwater@raleighnc.gov.
  6. Wash out equipment in a designated area, i.e. indoors or where you can use inlet protection.

Carpet Cleaning

There are chemicals and fibers from carpets that can go directly to our streams and creeks if you dump the dirty water into a storm drain. This water is not treated and is unsafe for the environment.


  • Vacuum the floor before cleaning it to reduce debris;
  • Do not pump wastewater into the storm drain;
  • Dispose of the water in a utility sink or toilet that’s connected to the sanitary sewer system; and,
  • Follow all cleaning product instructions for additional disposal requirements.

How to Prevent Water Pollution When Cleaning Carpets



Zachary Poole
Illicit Discharge Coordinator 

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