Carpet Cleaning and Pressure Washing Best Practices (PDF)

Anything that goes down the gutters and into the stormdrain ends up in our local waterways. Our cleaning activities can pollute waterways if not done properly. Please help us to protect our waterways by making sure that dirty water and cleaning solutions do not end up in parking lots, sidewalks, or other places where they will make their way into stormdrains.

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Pressure Washing
Carpet Cleaning
Cleaning Up Spills

Pressure Washing and Outdoor Surface Cleaning

Pressure washing is commonly done to remove dirt and grime from homes and other buildings to clean and to prepare a building for painting or other work, or to clean paved surfaces. At this time, the washing down of paved surfaces is only allowed for safety and sanitation. Only a bucket, a hose with a shut-off nozzle, a cleaning machine that recycles water, or a low-volume/high pressure water broom may be used to clean paved surfaces. Learn more about current water use restrictions.

Need to clean a paved surface? Try “dry” cleaning methods first

Instead of washing surfaces with water, try the methods below:

• Sweep the area clean of trash, dirt and other solid debris. Dispose of debris in the trash.
• Use paper towels, rags, mops, or kitty litter to clean up liquid spills. Dispose of the clean-up materials in the trash. If the spill was a hazardous material (such as motor oil or auto fluid), take the materials to a hazardous waste facility.

When pressure washing, always be sure to do the following:

Protect Stormdrains

If pressure washing is needed, pre-clean the area first. While pressure washing, prevent wash water from entering stormdrains.

Contain and dispose of the wash water

Plan to collect and dispose of the dirty wash water using the following strategies:

• If there are obvious low spots on the ground, you may be able to set up temporary berms and containment pools to collect wash water that flows from the area you are cleaning.
• When possible, collect the wash water and pump it into a sanitary sewer drain (sometimes a sewer clean-out can be used). Sump pumps and wet/dry shop vacuums can be used to pump the wash water.
• Wash water can also be drained to a landscaped area, as long as it does not overflow the landscaped area, contain hazardous materials, or create nuisance conditions.
• Other options include using vacuum booms, inflatable pipe plugs, wet/dry vacuums, or manual pumps to contain, transport, and discharge wash water into a proper disposal point.

Use environmentally friendly cleaning products

If it is necessary to use cleaning solutions along with the pressure washer, consider nontoxic or biodegradable products. While improper disposal of these products can still harm or kill wildlife, they are much less damaging than using toxic cleaning products that contain hazardous substances like hydrofluoric acid, sodium hydroxide, bleach, etc.

Don’t power wash surfaces that may contain lead paint

Paint can chip off when washed with high pressure water. Most paints are fairly benign, but lead-based paints can cause serious pollution problems when they enter waterways.

Carpet Cleaning

Professional carpet cleaning can generate a significant amount of dirty wash water. In order to protect our waterways, it is important to make sure that wash water does not enter the stormdrain system.

Wash water from carpet, drapery, or furniture cleaning must be poured into a sink, toilet, or other drain connected to the sanitary sewer. If no other option exists, wash water may drain into a pervious area, such as a lawn, however the wash water must not flow from there into the street, gutter, parking lot or stormdrain and biodegradable detergents must be used.

Never pour wash water into a parking lot, driveway, street, or any place where the wash water will flow into the gutter and down a stormdrain.

If there are no pervious areas or sanitary sewer cleanout drains that can be used, all wash water should be hauled away and disposed of into a drain that flows to a wastewater treatment plant.

Before disposing of wash water, it should be filtered through a strainer to prevent debris in the wash water from clogging the pipes. Debris collected from wash water can be placed in the trash.

If it is necessary to use cleaning solutions along with the pressure washer, consider nontoxic or biodegradable products. While improper disposal of these products can still harm or kill wildlife, they are much less damaging than using toxic cleaning products that contain hazardous substances like hydrofluoric acid, sodium hydroxide, bleach, etc.

Cleaning Up Spills

Accidents happen. If wash water or other liquid debris are spilled on the ground outdoors, it is important to act quickly to ensure that nothing enters the stormdrain.

If a spill occurs:

• Stop the source of the spill immediately.
• Contain the liquid. Consider using containment booms, vacuums, and absorbent materials so the spill does not reach stormdrains or streets.
• Absorbent materials may include products such as kitty litter, paper towels or rags to soak up the liquids. Always dry sweep up products such as kitty litter. Never wash anything down the stormdrain. 
• Dispose of the spill clean-up materials in the trash. If the spill was a hazardous material (such as motor oil or cleaning products), it cannot go into the trash. Residents can bring spill materials containing hazardous wastes to the household hazardous waste drop-off facility. Businesses have several options for disposing of their hazardous wastes, but they cannot use the free household hazardous waste drop-off.