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Show wash equipment ( especially pumps). For the purposes of this evaluation, an operating cost of $ 3,000 ( exclusive of water and wastewater costs) per year has been assumed. The closed loop system is a more complex treatment system than the clarification system. Although some manufacturers claim 100 percent recycle, a closed loop treatment system realistically can recycle approximately 90 percent of the water used. No separation of wash and rinse water is required. Closed loop systems consist of a skid- mounted package comprised of several individual treatment processes such as ozonation, oil/ water separation and filtration. The closed loop system can be used for either the friction or pressure wash system, but it would typically be used with the pressure system. The capital cost of a closed loop system is estimated at approximately $ 75,000 installed in a new facility. Costs would be higher for a retrofit. Operating costs ( exclusive of water and wastewater) are estimated at $ 3,750 per year. As new vehicle wash facilities replace existing ones, estimated water savings from recycling will range from 2,641 to 4,401 acre- feet per year. Cost Effectiveness An economic analysis was conducted using a rate of return of 6 percent and a useful life of 20 years with water costs assumed to be $. 80 per thousand gallons and wastewater disposal costs of $ 1.07 per thousand gallons. Analysis assumes the typical vehicle wash facility uses 35 gallons per car and averages 300 vehicles per day. Evaluation of a typical non- recycling system results in use of 3.82 million gallons, or 11.7 acre- feet, of water per year. Analysis of a friction type system using a clarification type recycling results in the savings of 2.07 million gallons or 6.20 acre- feet of water per year. This results in a capitalized cost of $ 3,183 per acre- foot of construction capacity. Analysis of a closed loop recycle system shows a water savings of 3.5 million gallons ( 10.48 acre- feet) of water per year. This gives a capitalized cost of $ 4,200 per acre- foot of annual yield. This is the subsidy required to induce a car wash owner to make an investment in recycling. This is substantially higher than the CUWCD conservation credit program will pay as federal cost share for water conservation, which is $ 1250 per acre- foot of annual yield. These costs apply only to newly constructed car washes. Retrofitting existing car washes would result in higher costs per acre- foot because most existing facilities may still have unrecovered capitalization costs and need modification. While many vehicle wash facilities, nationwide, are subject to local wastewater pretreatment requirements, none is known to be regulated in Utah. If, at some point in the future, vehicle wash facilitates are required to pretreat wastewater prior to discharge, the economics may favor recycle systems. Consumer Preference Vehicle washwater recycling is practiced only to a limited degree within the state of Utah, or throughout the U. S. There are two reasons for this. First, there is the perception that a vehicle wash system that uses reclaimed water will not perform as well as systems that use fresh water. This is particularly the case with a friction type of wash system. Most car wash owners, whether they agree with this perception or not, do not use these systems because they feel many people would choose a touchless fresh water wash over a friction recycle system. The cost savings are not great enough to risk loss of business. Second, the savings occur over time and require significant additional investment. The friction system requires an additional $ 30,000 investment and the closed loop system requires an additional $ 75,000 investment. 63 |