We all want our new, energy-efficient vehicles to look their best, and ecoconscious drivers want to extend their green lifestyle to include cleaning their car. Washing can provide some exercise and saves money, but the International Carwash Association reports that automatic car washes use on average fewer than 45 gallons of water per car, compared with 80 or more at home. Commercial facilities also drain wastewater into sewer systems to be treated or reused, while soapy do-it-yourself water can directly enter waterways via storm drains unless it’s in an area that filters into a local aquifer.

Here are some helpful tips.

Conserve water. For DIY folks, the U.S. Environmental Protection Agency recommends using a bucket instead of a hose for washing a section at a time, and then quickly rinsing using a pistol-grip hose nozzle, and also washing the car on gravel or a lawn, so wastewater doesn’t flow off pavement or sidewalks and down a storm drain. Be sure to use phosphate-free, non-toxic biodegradable soaps and waxes.

Check under the car. Grime, dirt and salt may have accumulated in crevices of the undercarriage, especially in colder regions, so spray underneath, too.

Be observant. A fender-bender, stray pebbles or the impact of another car door may have chipped exterior paint. According to the National Institute for Automotive Service Excellence, corrosion, acid rain, storm damage and harsh sunlight can also mar body paint and expose metal surfaces. Treat these blemishes with a stop-rust spray and touch-up paint before they spread.

Sources: Environmental Protection Agency, National Institute for Automotive Service Excellence, International Car Wash Association, eHow.com