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Pollution Prevention for Surface Cleaning

Water Hose

Outdoor pressure washing and surface cleaning activities, such as the cleaning of building facades, rooftops and pavements, can readily degrade water quality if the washwater is allowed to discharge to the stormwater drainage system. The washwater from these activities can be contaminated with detergents and cleaning agents, suspended solids, organic matter, trash, heavy metals and numerous other pollutants present on the surfaces being washed.


Follow the practices below to help prevent stormwater pollution and harm to our waterways and environment. 


  • Identify and cover all nearby stormwater drains with impervious barriers such as berms, plugs or rubber mats, or screens as needed. Ensure that drain covers and the amount of washwater generated will not flood the area or adversely affect vehicle or pedestrian traffic.

  • Create a containment area with temporary curbs, berms and tarps as needed to keep wash water contained.

  • Consider surface cleaning only using water; when using detergents and cleaning agents, use the least toxic product needed to get the job done.

  • Manage and dispose of washwater from pressure washing and surface cleaning appropriately depending on the site and type of cleaning:

  • Never dispose of washwater containing soap or other cleaning agents, grease, oil, solids, floatable debris or other pollutants to a stormwater drain, drainage ditch or surface water. Discharge washwater to a holding tank truck or sanitary sewer in accordance with local wastewater requirements.

  • Pressure washing wastewater that contains visible debris or residue, soap, detergent or other cleaning agents, or excessive amounts of any pollutant, may not be left on paved surfaces to evaporate, because that residue will eventually be discharged to the stormwater drainage system.

  • Pressure washing and surface cleaning activities should not be undertaken during rain events or when rain is eminent.

  • Minimize water use by using high pressure, low volume nozzles; this reduces the volume ofwastewater that needs to be properly disposed.

  • Instead of pressure washing and other wet surface cleaning, consider using alternative dry methods.

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