Prevent Pollution from Pressure Washing and Graffiti Removal

Pressure washing and graffiti removal generate pollutants that are harmful to human health and the environment. Wash water from these activities is prohibited from flowing to the city's stormwater system. Follow these best management practices to properly contain wash water and prevent pollution.
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The City’s Role

The federal Clean Water Act requires cities to set rules and regulations to protect the city's sewer and stormwater systems and its watersheds. Environmental Services works with business and industry to meet these requirements.

When pressure washing, directing or allowing wash water carrying soap, paint, teargas, feces, dirt, chemicals, or other pollutants to enter the roadway or a storm drain violates City Code and may result in penalties. Many storm drains in Portland carry stormwater directly to our rivers and streams without treatment. The pollutants in the wash water can hurt water quality in streams and harm fish and other aquatic life.

Rules and Regulations

Portland City Code 17.39 prohibits the discharge of wash water from pressure washing and graffiti removal into the stormwater system. The discharge of pollutants may result in investigations, issuance of penalties, and required corrective actions.

Portland City Code 17.32 prohibits directing water from any source to run onto any City sidewalk, street, easement, or right-of-way without first obtaining authorization or approval.
Portland City Code 17.34 requires approval to discharge to the sanitary sewer. Pressuring washing businesses can apply for Mobile Washer Discharge Authorization.

Prevent Pollution through Best Management Practices

Before and During

  • Schedule cleaning during dry weather.
  • Place temporary barriers around stormwater inlets and storm drains.
  • Sweep up all sand blasting materials, paint particulates, and other visible solids.
  • Prevent wash water from leaving the work area.
  • Prevent wash water from entering storm drains.
  • Divert only non-toxic and non-hazardous wash water onto a vegetated or unpaved area on the property to allow for infiltration.
  • Never allow wash water to infiltrate into a green street planter, rain garden, or other stormwater management facility either onsite or along the road.
  • When possible, don't use cleaning products that contain hazardous or toxic substances.
  • When possible, choose cleaning methods that don't require water like sweeping and brushing.
  • Collect wash water using a wet/dry vacuum for disposal.
  • Train employees on the proper procedures to prevent pollution.

Clean Up and Disposal

  • Wash water containing hazardous/toxic chemicals or solvents will need to be disposed of at an industrial wastewater treatment facility that is permitted to accept and treat the wash water.  
  • Wash water containing only detergents and some paint residue may be suitable for discharge to an onsite sanitary sewer drain. Contact Environmental Services for information.
  • Businesses that use pressure washing to remove graffiti or clean surfaces and would like to discharge the resulting wash water to the sanitary sewer must apply for and receive a Mobile Washer Discharge Authorization.

Failure to implement applicable best management practices listed above may result in the discharge of pollutants which is a violation of Portland City Code. The City will issue enforcement action in the form of a civil penalty if pollutants are discharged from your facility. Appropriate measures to prevent the discharge of pollutants are required.