How Does a Waterless Urinal Work?

The waterless urinal is a significant advancement. There’s no running water and no flushing involved. With water becoming an ever scarcer commodity, anything that can cut down on usage is to be welcomed. In the case of the waterless urinal, it can save huge amounts of water when used commercially. Even in the home, it can add up to huge savings.

The Science

The science behind the waterless urinal is quite simple. There’s a sealing liquid on the top of the urinal through which the urine passes. The sealant is oil, and as the urine is denser, it sinks below it. The fact that it’s trapped beneath a seal means that no odor escapes into the bathroom.

The Technique

Before reaching the sealant layer, the urine passes through a filter. This catches any debris and keeps it. From there, the flow is slowed down before it reaches the sealant. This is vital to stop displacement of the oil, which could send it down the waste pipe. Instead, the urine filters down through the sealant. If there are any air bubbles in it, these will rise before escaping so the urine remains in a low oxygen atmosphere. Removing the urine into the sewer system is a basic matter of displacement. Everything is accomplished without the need to flush, and this is completely achieved without water.


There are two types of waterless urinals. One utilizes a cartridge that contains sealant. Whenever the sealant needs to be replaced, as it does periodically, the old liquid is replaced. The alternative non-cartridge system has the sealant poured in manually via the drain hole. From there, it settles naturally into a level.


There are now several companies that produce their own take on the waterless urinal, with all of them using similar technology. It’s all part of a movement to make everything greener and conserve resources. Previously, the greatest hurdles to such an item were health and safety and other environmental issues. Those have been overcome, thus, making the adoption of waterless urinals very feasible.

By their very nature, waterless urinals will mostly be used in commercial environments, as most people don’t have separate urinals in their homes. If you consider the number of them currently in use in restaurants, stores, bars, gas stations and other places, the amount of water that can be saved in a year is huge.


As there’s no mixing of water from the flushing and the ammonia in the urine, there’s absolutely no odor. It’s the combination of these two things that causes the smell. As the urine is trapped below the sealant, even if a minute amount of water entered, there would still be no smell.


The sealant layer is biodegradable. You can also use any type of cleaner on the waterless urinal without damaging the sealant layer. That makes them very versatile. Its 2 inch internal drain line means that it’s easy to use a snake on the unit if necessary.