A 2003 Pacific Institute research titled "Waste Not, Want Not: The Potential for Urban Water Conservation in California" (pdf) tells us that if California's water-use was as efficient as readily available technology allows it to be, a saving of 33% - from 185 gallons per capita per day (gpcd) to 123 gpcd — could be achieve. "Despite their comparatively small use, individuals and businesses can play an important role in conserving water." With that in mind, the people at Triple Pundit have conducted this case study (pdf) on the cost benefit of using flushless urinals at the Kaiser Permanente French Campus Facility in San Francisco.For those not familiar with the fascinating world of urinal technology: "Conventional urinals use at least three liters of water per flush (about a gallon), whereas flushless urinals need neither water nor a flushing system [...] Special glazes give sanitary-ware urinals a pore-free surface, while urinals made of synthetic material have a long-lasting gel coating that repels liquids. The urine flows off the smooth surface of the urinal into a siphon. [...] The siphon contains a liquid sealant that has a specific density that is lighter-than-water. This floats to the top, allowing the urine to flow through it and away, taking any odors with it. The liquid sealant remains in the siphon. Flushless urinals have no joints or cracks in which bacteria can colonize. The special surface repels most liquids and impurities. Cleaning therefore involves less cost and effort than with conventional systems, and strong toilet cleaners are unnecessary."
The conclusions of the case study are quite interesting. Even using "worse case scenario" numbers, replacing current urinals with flushless ones at the French Campus would lead to $800 of savings, while the best case scenario would result in savings of around $40,000. Obviously, doing nothing it the most costly option.
Final words: "Therefore, in pure economic terms there is no question that investing in 14 flushless urinals for the French Campus would be a positive financial decision."
Good job, Triple Pundit (and in particular Nick Aster, Steve Kropfl, Kathryn Zender).