What About Pressure Washing of Building, Parking Lots, etc?

Water run-off from power-washing is allowed in the storm drain only when thefollowing 3 things are true: (1) the water used is clean and doesn’t contain anysoaps, detergent, degreasers, solvents, etc; (2) the surface being washed is something normally exposed to the elements, such as a building face or parking lot; and (3) the surface is not unusually contaminated – such as through an oil or chemical spill. In all other cases, power-washing discharges must be captured and hauled to a disposal facility or it must be discharged to the sanitary sewer. If you are involved in the commercial power washing, please contact the City for further details.

The Problem

Most power washing activities are conducted outside. This often results in the discharge of wastewater to the storm drain, unless the equipment operator takes steps to collect and dispose of it legally. Discharge of power washing wastewater to the storm drain is prohibited because it contains pollutants from the objects or surfaces being cleaned and/or from the cleaning compounds being used. Even cleaners labeled “biodegradable” and “non-toxic” may be harmful to aquatic life, especially after cleaning various surfaces (e.g. dumpster areas, parking lots, equipment and more) that contain fats, oils, greases, chemicals (such as herbicides, insecticides, pesticides, solvents, anti-freeze and fertilizers), as well as other substances.

Power washing wastewater that enters storm drains flows directly into lakes, rivers, and streams. This water is not treated or cleaned to remove pollutants. Pollutants discharged to the storm drain harm fish and wildlife and contaminate recreational sites and drinking water supplies.

If you have any questions, please call the Public Works Department at 281-275-2450.