USPS Stormwater Policy Reminder: Vehicle Washing

The United States Postal Service® (USPS®) has established policies to reduce pollution from stormwater and snowmelt, which can cause hazardous chemicals and pollutants to enter the environment and harm rivers, streams, lakes, and coastal waters. These policies require employees and suppliers to take specific actions to minimize pollution and protect water quality.

USPS has a “Zero Discharge” policy for stormwater. This means USPS or USPS third-party contractors cannot release or discharge pollutants (i.e., oil and grease, metals, acids/bases, or other such chemicals) into stormwater systems. This policy includes preventing vehicle wash water from entering stormwater drains.

Vehicle washing must be conducted inside vehicle wash bays at Postal Service™ vehicle maintenance facilities (VMF) or conducted outside by third-party vehicle washing suppliers that use approved zero discharge washing methods. Sites that do not have an available VMF or third-party vehicle washing supplier must use either an on-site dry-wash/waxing process or take the vehicle to an off-site car wash facility to ensure compliance with environmental requirements.

Postal Service sites using third-party vehicle washing services must establish contracts through the Vehicles, Delivery, and Industrial Equipment Category Management Center (CMC) using the nationally-approved statement of work for vehicle washing. Contracts established through the CMC require suppliers who wash vehicles to use either a dry wipe process or a wet wash that collects and contains wash water for proper off-site management.

To establish a vehicle washing contract for your location, contact Carla Van Istendal by email at or by phone at 215-863-5397.

For more information, refer to the Vehicle Washing Requirements Environmental Compliance Bulletin at