Surface Cleaning

  1. Any substance, including surface cleaning wastewater, that enters the storm drain system flows directly into lakes, rivers and streams without treatment.
  2. Discharging pressure washing-generated wastewater into the storm drainage system violates local, State, and federal stormwater regulations.
  3. The use of Best Management Practices (BMPs) during surface cleaning can reduce the amount of pollution entering our waterways (i.e., rivers, lakes and creeks).
  4. Avoid using soap!  Even biodegradable soap is harmful to aquatic life.  Before you use soap, test to see whether hot water under pressure will do the job.
  5. Several options are available for collecting wastewater, including vacuum pumps, booms/berms, portable containment areas and absorbents.
  6. Wastewater should be collected and disposed into the sanitary sewer in accordance with the local sanitation agency regulations.
  7. Hazardous waste of any kind (e.g., lead-based paint, oils, antifreeze, solvents, etc.) is prohibited from entering the sanitary sewer system and any wastewater that constitutes a hazardous waste must be properly disposed of at an appropriate hazardous waste collection center.
  8. Eliminating the use of chemicals or reducing and/or replacing toxic chemicals (e.g., hydrofluoric acid, muriatic acid) with less toxic chemicals reduces the likelihood of generating hazardous waste.
  9. Discharging wastewater onto landscaped/dirt areas requires the property owner’s permission and is authorized only when the wastewater does not create a nuisance condition, flow into the storm drain system, and/or contaminate soil.
  10. To learn more about pollution prevention practices for surfacing cleaning in the Napa Countywide Stormwater Pollution Prevention Program (NCSPPP) Surface Cleaning Guide (English)