In a research paper titled Waterless Urinals – A Technical Evaluation, Annette L. Stumph of the U.S. Army Research and Development Center provided some interesting statistics, including:
- Installing a waterless urinal in place of a conventional type that uses 1 gallon per flush could save up to $875 worth of water annually (based on a public urinal that is used 75 times a day and basing the calculation on the water rates in Seattle, Washington).
- In volume terms, this represents a savings of 27,375 gallons annually per modern urinal that uses 1 gallon per flush.
- For older urinals using 3.5 gallons per flush, the figure rises to 95,812 gallons of water saved per year per urinal.
Obviously, these figures represent only the gross savings in water terms and do not take the cost of operating waterless urinals into account. The study did also factor this in, though, and found that even after the cost of replacement cartridges, sealant etc. was included, savings of between $130 and $830 per year were still achievable.
Although this study is a few years old, it does still clearly show that significant savings can be achieved by replacing conventional urinals with waterless urinal units, both in terms of financial cost and water wastage.
It is also interesting to note the big difference between the minimum and maximum net cost savings ($130 to $830). This is because the cost of items like replacement cartridges can vary greatly from brand to brand. In order to derive maximum benefit from switching to waterless urinals, it is necessary to carefully choose which cartridges to use. Some brands to consider and evaluate against each other are Falcon, Sloan, Kohler, hybridH2o and Smarty Bee.