1.0 Background
Commercial vehicle washes present a two-part opportunity for water conservation based both upon differences in construction and upon operator preferences. In this chapter, the functional difference between vehicle wash systems and categories are examined first, followed by a discussion of the operational measures employed by these businesses. The water savings potential and cost benefit estimates are presented for each of the different types of vehicle washes.
Commercial carwashes are categorized as either conveyor, in-bay automatic or self-serve, and include those carwashes that are available for public use at stand-alone carwash facilities, as well as those alongside convenience store, lube shops or gasoline stations. The three basic types of equipment within those categories are also used for truck and bus washing and for washing vehicles at dealerships and rental agencies. Some truck washes are available commercially, but many are for washing fleets and are typically located on private property. Conveyor and in-bay automatic carwashes can be constructed as friction or touch-less, which further affects water use. All these basic types of carwashes can be retrofitted for or built with water reclaim systems. The International Carwash Association summarizes the “Steps in a Professional Car Wash Process”1 that affect water use as follows:
• Pre-soak. An automated nozzle or hand held spray.
• Wash. High pressure spray or brushes with detergent solution.
• Rocker panel/undercarriage. Brushes or high pressure sprays on sides and
bottom of vehicle.
• First Rinse. High pressure rinse.
• Wax and Sealers. An optional surface finish is sprayed on the vehicle.
• Final Rinse. Low pressure rinse - with fresh or membrane-filtered water.
• Air Blowers. Air is blown over the vehicle to remove water and assist in
drying.
• Hand Drying. The vehicle is wiped down with towels or chamois cloths on
site. In full-service washes these are then laundered in washing machines
on-site.
To differentiate among the three categories, in a professional conveyor car wash, these steps are performed by separate spray arches and/or brushes. In the professional in-bay automatic, there is a set of nozzles through which all processes are performed, except in some cases where brushes may be used for the wash cycle. In professional self-service car washes there may be a brush for the wash cycle, but all other functions are performed through a hand-held wand.
In addition to the three basic carwash types, mobile washing services, detailing services including hand washing, and some industrial vehicle washing systems exist with unique challenges and opportunities for water-use efficiency. These will be dealt with at the end of this chapter.