You wouldn’t wash your car in the ocean so why would you let your soap, grease and dirty water enter the storm drains?
When you wash your car at home, the water you use can flow into the street, picking up dirt, chemicals, and trash along the way. This water then runs into storm drains, where it flows untreated into channels, harbors, and the ocean. You can help protect the environment by using commercial car washes. If you must wash your car at home, use a trigger nozzle to minimize water usage. Washing your car on grass or gravel also helps absorb the water.