When  cars are washed, dirty water containing soaps or detergents, residues from exhaust fumes, gasoline, motor oil and heavy metals falls onto the pavement and flows into nearby storm drain inlets.

Soaps or detergents used, even biodegradable soaps, can harm fish and small invertebrate animals (e.g., worms, clams, and insects) that provide food for fish. Soaps contain surfactants that may harm fish by destroying the external mucus layers that protect them from bacteria and parasites, and may also cause damage to their gills. Detergent concentrations of 5 parts per million can kill fish eggs.

Even if soaps or detergents are not used, the wash water will pick up grease, oil, elements from brakes linings, residues from exhaust fumes, rust, benzene and chromium.

Follow these good practices for car washing:

1. Select a site for washing where the water can soak into grass or gravel.

2. Use only soaps or cleaners labeled non-toxic, phosphate-free or biodegradable, which are usually vegetable-based or citrus-based. Do not used acid-based wheel cleaners or engine degreasers.

3. Minimize the runoff of soapy wash water by using the following methods: 

• Use an adjustable nozzle on the hose that will shut off the flow of water. Turn off when not in use to help conserve water.
• Use the least amount of soap possible. Put the soap in a bucket to make soapy water for use with rags or sponges.
• Don't empty buckets of soapy or rinse water into the parking lot, street, gutter or storm drains. Instead, empty buckets of soapy water into the sanitary sewer system (e.g., sinks or toilets).

4. Only wash the exterior surface of the vehicle. Don't wash the engine, undercarriage, or transmission area.

Following these steps will help keep our creeks clean by reducing pollution impacts on our local waterways.