Don’t Wash Your Car in Your Driveway August 12, 2018 Email Washing your car in your driveway is bad for local water. Why? Everything you wash off your car — soap, road muck, traces of exhaust residue, motor oil and gasoline — will run into the nearest storm drain, and storm drains flow unfiltered into local waterways. This isn’t bad only for water quality. Car residues contain heavy metals, hydrocarbons and other chemicals that are toxic to aquatic wildlife. A little pollution adds up quickly across whole cities, and even gentle soaps can break down the protective layers on fish and their gills, impairing breathing and making them susceptible to infection. Wash your car at a car wash instead, where the water is collected and treated so that it can be safely reused. If you are going to wash your car at home anyway, follow these tips: Use nontoxic, biodegradable soap. Wash your car on a lawn or other absorbent surface, so there is less runoff. Wring sponges or rags into a bucket, and empty the bucket down an indoor drain. Create your own car-washing kit with this guide from Only Rain Down the Drain. To learn more about protecting local water supplies, visit our Clean Water page.