Estimate water savings from a vehicle-wash reclamation retrofit using EPA WaterSense at Work

Steps

1. Download EPA's WaterSense at Work Section 5.5 Vehicle Washing guidance and identify your wash type: conveyor (friction or frictionless), in-bay, or self-service.
2. Record current per-vehicle water use if metered, or use the guide's cited International Carwash Association averages if not (conveyor ~75.0 gallons/vehicle, in-bay ~55.0 gallons/vehicle).
3. Calculate annual water use with Equation 5-1: Water Use per Vehicle x Vehicles Washed per Day x Days of Facility Operation per Year.
4. Apply Equation 5-2 to estimate retrofit savings: Current Water Use x 0.5, reflecting the guide's cited ~50% average freshwater reduction from reclamation systems (facilities using reclamation filled ~51% of needs from reclaimed water on average).
5. Compare estimated annual savings to a typical retrofit cost (the guide cites roughly $35,000 for equipment and installation) against local water/wastewater rates to estimate simple payback.
6. Cross-reference Table 5-4 in the guide for the minimum treatment level (filtration, reverse osmosis, or deionization) required before assuming reclaimed water is usable at a given wash stage.