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Guide to the Mobile Washer Program

Guide
Wash water generated from commercial mobile washing activities is prohibited from entering the City's stormwater system, streets, or right-of-way. To discharge wash water to the sanitary or combined sewer system, businesses must apply for and obtain a Mobile Washer Discharge Authorization.
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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.

Many storm drains in Portland flow directly to a river or stream without treatment. Wash water generated from commercial mobile washing activities can contain soap, paint, teargas, feces, dirt, chemicals, or other pollutants. If allowed to flow to a stream or river, pollutants reduce water quality and can harm fish and other aquatic life.

Rules and Regulations

Portland City Code 17.39 prohibits the discharge of wash water 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. Mobile washing businesses must apply forMobile Washer Discharge Authorization.

Who Should Participate

Examples of businesses that require a Mobile Washer Discharge Authorization include:

  • Mobile fleet washers.
  • Mobile power washing services.
  • Graffiti removal services.
  • Trash receptacle cleaning services.

Prevent Pollution through Best Management Practices

To obtain a Mobile Washer Discharge Authorization, businesses must follow these best management practices to ensure proper collection and disposal of wash water:

  • All mobile washing activity must be performed on the customer’s property or site. Wash water must be contained onsite and cannot be allowed to discharge to the right-of-way or stormwater system. City Code prohibits washing in the right-of-way.
  • The wash area must be washed down after use. No soap residue may remain on the site.
  • The water must be collected and discharged to the sanitary or combined sewer system at an approved location.
  • Wastewater containing fats, oils, and grease (FOG), polar and non-polar, must be treated through an approved grease removal device prior to discharge to the sanitary sewer. 
  • Mobile washing activity conducted at job sites where stormwater management is regulated under a control mechanism, such as a National Pollution Discharge Elimination System (NPDES) permit or a No Exposure Certification (NEC), must adhere to the requirements of the facility’s Storm Water Pollution Control Plan (SWPCP), if applicable.
  • The pH of the discharge to the sanitary or combined sewer must be within 5.0 and 11.5. This must be verified by onsite monitoring prior to discharge using pH test strips or a portable pH tester.  
  • The rate of discharge must not exceed 50 gallons per minute.
  • A site-specific work plan documenting the measures taken to prevent pollutants from entering the stormwater system must be maintained in service vehicles performing washing operations. A copy of the site drainage map and the Mobile Washer Discharge Authorization must be maintained as well.

Mobile Washer Discharge Authorization Limits Types of Discharges

A Mobile Washer Discharge Authorization limits the types of discharges allowed.

  • Mobile Washer Discharge Authorization applies only to exterior surface washing.
  • Wash water discharges associated with internal compartment washing (tanks, tankers, etc.) are not permitted under this Discharge Authorization.
  • Wash water discharges associated with internal washing of drums, totes, or containers used to store commercial product or process wastes are not permitted under this Discharge Authorization.
  • Wash water discharges associated with exterior coating removal (e.g. paint stripping) are not permitted under this Discharge Authorization.
  • Treatment for pH and metals may be required if brightener chemicals are used on vehicles.

How to Apply for Authorization

Businesses wishing to receive a Mobile Washer Discharge Authorization must apply for certification. Applicants should be prepared to provide a Work Plan and Site Drainage Map for each customer’s property. As a condition of continued authorization to discharge, businesses must submit an annual certification of compliance.

Apply for 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.