In mid-September, the International Carwash Association released a new study on Water Use, Evaporation, and Carryout in Professional Carwashes.This is the second water research study undertaken by the association. The first, introduced at Car Care World Expo in Chicago in 2002, covered similar ground under the title Water Use, Wastewater Quantity and Quality in Professional Carwashes.

The 2002 study covered 32 car washes in three distinct geographical areas (12 in Boston, 11 in Orlando, and nine in Phoenix) and in three industry categories (11 self service, 11 in-bay automatics, and 10 conveyor washes). The study found that, geographically, there was no statistical difference in the gallons per car used or in the evaporation/carryout rate. Significant disparities were found, however, in the water usage and evaporation/carryout among the three industry segments.

The conclusion: climate does not drive water usage, equipment does. In-bay automatics (touchless) were found to use the most freshwater per car washed and had an evaporation/carryout rate nearly 50 percent higher than conveyor washes. Self-serves used water most sparingly, but recorded the highest evaporation/carryout rate.

Considering the results from the 2002 study, it is therefore no surprise that the just-released 2017 study confined its inquiries to one area in one state; it chose Northern California. This time data was collected from 12 car washes — six conveyor operations and six in-bay automatics — all of which reclaim water and, with one exception, employ a reverse osmosis system. In the 2002 study only five of the in-bay automatics and four of the conveyor washes had reclaim equipment allowing for a comparison of water usage between the have’s and the have-not’s. The absence of self-serve washes in the current study was a bit of a surprise.

As much as the water study serves to encourage operators to save and reclaim water, it also offers the opportunity for operators to save money. In jurisdictions where sewer charges are imposed on actual discharge to the sewer rather than employing freshwater usage as the measure, the study’s findings can add up to significant savings for some washes. Self-serve washes, having recorded the highest evaporation/carryout rate in 2002, could potentially have benefitted the most (percentage wise) from inclusion in the new research.

With regard to the two segments studied, results were in line with those found in 2002. At an average of 30 gallons per car, freshwater usage in conveyor operations was down some from the previous study. The average evaporation/carryout rate was slightly higher than in 2002 at 21.4 percent. For in-bay automatics, fresh-water usage averaged 44.8 gallons — well above the figure for conveyors, as was the case in 2002. The average evaporation/carryout rate was 20.6 percent.

Only one of the in-bay automatics in the study employed friction equipment. Surprisingly, it used more freshwater per car than three of the five touchfree-equipped operations — significantly more in two cases.

Operators should take note of the potential savings revealed by this study and the efficacy of a water-reclaim system. The drought that got started in 2012 in California officially ended only last year and already the next one is being foreseen. Writing at, Julie Hill-Gabriel, vice president of Water Conservation at the National Audubon Society and Christy Plumer, chief conservation officer for the Theodore Roosevelt Conservation Partnership warn that this year the Colorado River Basin received only about a third of its average annual supply of snow-melt runoff and point to a projection of a 57 percent chance of shortages on the Colorado River in 2020 and beyond.