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Show The cost savings from lower water bills are not currently a factor with the industry, because water costs are a minor component of overall business costs. Water recycling and reuse is considered a competitive necessity by the commercial laundry industry due to significant heating costs and the benefit of reduced discharges to sewer systems. Vehicle Wash Facilities Background Various types of wash systems, including self- service and automatic, are presently being used in the state of Utah. The hand- held, self- service wash is reported to use approximately 10 to 20 gallons of water to wash each vehicle. The automatic drive- through wash uses approximately 25 to 45 gallons per vehicle. Wash owners select different combinations of wash equipment for their facilities. The number, design, age and maintenance of this equipment will affect the volume of water required to wash each vehicle and the resulting wash quality. An estimated one- third of the wash facilities in the Salt Lake Valley are self- service washes, and two- thirds are drive- through washes. Drive- through wash systems may be further classified based on the cleaning mechanism. Two types of systems available are the friction system and the pressure system. The friction system uses large brushes that contact the vehicle to break the road film and clean the vehicle. Pressure systems are also referred to as touchless systems. These systems use high- pressure water to wash the vehicle and therefore no brush is required to physically contact the vehicle. The touchless system requires more chemical surfactant ( soap) than the friction system to effectively clean a vehicle. Some washes use a combination of the friction and touchless technologies. The friction system is more conducive to recycling than the touchless system. Grit, clogs and wears out the nozzles required for the high pressure system. This results in increased cost and down time. The same grit that wears out nozzles is thought to damage a vehicle's paint. Several wash facility owners commented that brush systems can cause damage to a vehicle's paint even if fresh water is used throughout the entire wash. Brushes have also been blamed for removing antennas, license plates, hood ornaments and other parts which protrude from a vehicle. For these reasons, many owners use only the touchless system. Wastewater produced from vehicle washing contains high quantities of total solids, suspended solids, oil and grease, and dissolved organic matter. The composition varies seasonally and geographically. In winter months in locations where salt and sand are prevalent on roads, the wastewater contains significantly higher concentration of salt and grit. In dry areas, more dust and dirt will be present in wash water. The quantity of contaminants in the wash water depends on the road surface and conditions to which the vehicle has been exposed ( gravel, paved, etc.), weather factors and the length of time between washes. The actual concentration of contaminants in the wash water is directly related to the quantity of water used for washes, the quantity of and type of detergents used for washing, and the quantity of contaminants washed off the vehicle. Therefore, if less water is used for washing a vehicle, the concentration of the contaminants is higher in the wash water. In terms of water conservation and water quality, generally less water is used per wash at a commercial facility than from vehicle washing at home. In addition, contaminants washed from the vehicles are controlled through pretreatment programs and treatment at municipal wastewater reclamation facilities. Washing vehicles at home can result in large volumes of wastewater directed to storm sewers. 60 |