The Perceived Environmental Impact of Car Washing
PDF doc:
http://bikeforpeace.org/carwash.pdfConclusion
Numerous metals and other chemicals exceed EPA standards in hand wash stations, highway runoff studies and commercial car washes, and common detergents are known to harm and alter aquatic organisms. Solutions range from simply using little to no detergents while washing vehicles on lawns to borrowing equipment from the local government for water filtration. Though no enforcement has been promulgated by the EPA, many cities, environmental organizations and government units have taken action in the USA and Canada. Enough evidence exists for the West Coast, Texas, Canada and the EPA to see the metals, detritus and detergents from car washing as a threat to waters in North America.
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It sounds like It depends on what's in the products used (at home or elsewhere)
http://www.carwashguys.com/fundraisers/ch2.html#CAR%20WASH%20PRODUCTSHow do I know if the products I’m using are safe for the environment?That’s a good question. The answer is they aren’t and no product is allowed in the storm drain. So your next question is, "If I use the waste wash water to water the grass in front of the school or a flower bed near a gas station, how do I know if it will kill the grass or plants?"
This question we can answer. Every product has a Material Safety And Data Sheet (MSDS). Read through the sheet and see if the diamond at the top of the sheet has a number higher than one in the box on the left. If it does, it will affect organic life. Look for products that have only ones or zeroes in the boxes in the diamond code at the top.
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http://planetgreen.discovery.com/transport-tech/vroom-vroom/car-wash.phpSudsing up your car in the driveway may get your hub caps to sparkle, but the untreated wastewater can also run off Ol' Betsy straight into storm drains and eventually into rivers, streams, lakes, and wetlands, where it can degrade water quality and poison aquatic life.
The average home-brewed car wash uses more than 500 gallons of water, according to the U.S. Environmental Protection Agency. (For a sense of scale, it takes 25 gallons of water for a 5-minute shower and 35 minutes to fill a regular-size bathtub.)
Commercial car washes, on the other hand, use around 32 gallons of water per car, according to the International Carwash Association. They're also required by the 1972 Clean Water Act to drain their wastewater into sewer systems, where it gets treated before it's flushed back into the environment. Plus, many commercial car washes recycle and reuse their rinse water, which they send blasting through a computerized system of high-pressure nozzles and pumps to minimize water use.
Another alternative: The waterless car wash, which can be wiped off without the need to rinse. Eco Touch, Freedom, and Lucky Earth are just a few of the water-saving options that will get your auto gleaming like new.