The water can be applied evenly and gives the run off a spread effect. By the time you've washed 150-300 cars at a fundraiser you too will become very efficient with the water.You may also be able to borrow a pressure washer from a local painting contractor.If you are extremely careful with your water usage during your fundraiser, you can beat even the best recycling car wash, which still uses around fifteen gallons of water per car. They use them a lot to clean the exterior of homes and commercial buildings before painting. Thus the water that reaches the ground evaporates quickly. So use shut-off nozzles or kink the hose when you're not spraying.Fixed site car washes also conserve their water. Nearly two-thirds of the soap/rinse cycle water can be recycled. The average fixed site car wash uses four gallons (pre-wash) plus misting system twenty-two gallons (sixty-six divided by two-thirds that is recycled) in the soap/rinse cycle bringing the total to twenty-six gallons of water per car. You will also have a lot less water to worry about that might be going into the storm drain.Working with a local professional can be very efficient. That is why they are allowed to stay in business during a water shortage. Approximately 150 cars with 3,600 gallons of water is generally the maximum amount of cars washed at this type of function using conventional methods. This is fifty times more efficient. And some self-serve car washes claim they use as little as 6.If you will be using a straight garden hose remember that fundraisers generally use approximately 3,600 gallons of water; If you use a pressure washer during your fundraiser you can wash twenty cars with one capful of soap in a two-thirds filled five-gallon water bucket. These cars combine to lower your wet/rinse cycle to about thirty seconds of spray time or 1. Expect to pay $300 for a good electric unit and $500 to $800 for a decent gas unit. This dirty water is mixed with white sudsy soap and used during the car wash soap cycle. Four gallons of water is used during the pre-wash cycle. They only use 2. They use seventy gallons of water per car during their complete car wash cycle. See if someone in your group has a parent who is a painter. A car that needs to be soaped will have a wet/rinse cycle of about one minute and will use about two gallons of water. We saved the City of Thousand Oaks, California 2,650 gallons of water that day and made the kids a substantial amount of money.2 gallons of water per car. This water never reaches the storm drains.