10 Fascinating Facts About Waterless Urinals

In the United States, there are roughly 8 million urinals in operation, spread across everything from small office spaces and towering skyscrapers to massive sports stadiums [source: Waterless]. Around 100 million people use these urinals, consuming approximately 160 billion gallons (605 billion liters) of water annually [source: Waterless]. However, alternative waterless urinals could drastically reduce this consumption. Imagine cutting that 160 billion gallons by half—or even eliminating it entirely.

Although waterless urinals haven’t become a mainstream choice yet, it’s easy to see why. The term “waterless urinals” tends to raise a lot of questions. “Do they smell?” “Are they hygienic?” “Where does all the urine go if you don’t flush it?” Keep reading to get answers to these and other queries about these innovative water-saving fixtures.

10: How Waterless Urinals Function

At first glance, a urinal that doesn’t require water may seem like a complex device with intricate parts, pumps, and valves. However, waterless urinals are actually quite straightforward. They typically rely on gravity and a specially designed trap chamber filled with a liquid known as sealant, which guides waste cleanly down the drain [source: Waterless]. The sealant’s formulation varies by manufacturer, but all are lighter than water, don't evaporate, and are often made partly from oils such as vegetable oil [source: Waterless].

When you look at a waterless urinal, you’ll notice a circular dome surrounded by small channels that allow for water movement. This dome is the trap, a removable cartridge that makes water-free draining possible. In the most common design, waste enters the trap via a series of slits along the top of the cartridge. The urine then passes through the sealant, which remains on top due to its lighter weight compared to water [source: Reichardt]. Afterward, the urine flows down into a central reservoir. An open pipe at the center of the reservoir channels the liquid into the bathroom's waste line, the same one used by traditional urinals. As the urine fills the reservoir, it eventually overflows once the liquid level rises above the pipe’s rim, causing the excess to drain out [source: Reichardt]. At any given time, there’s always a small amount of urine in the reservoir, with old waste being replaced by fresh waste as more users come along.

9: No Odor with Waterless Urinals

The term "waterless urinal" might evoke the image of a malfunctioning, unpleasant-smelling device—certainly not something you would want to use or have in your home. In fact, odor control was one of the primary challenges during the development of waterless urinals [source: Davis]. Sewers are filled with a variety of smells and gases, which can pose health risks if released. The key function of the sealant in waterless urinal trap cartridges is to prevent foul odors from escaping through the pipes [source: Waterless]. The sealant floats on top of the urine in the trap, ensuring that odors are sealed inside. Additionally, because there’s no flush involved, there's no risk of urine pooling in the bowl. Waterless urinals feature ultra-smooth bowls with a steep slope, ensuring that all liquid flows directly into the reservoir without any stagnant liquid [source: Waterless].

8: Waterless Urinals Have Fewer Bacteria

Urine is mostly sterile when it leaves the body. In conventional toilets, it’s the mixing of urine and water that fosters the growth and spread of bacteria [source: Reichardt]. When urine’s particles and minerals mix with the water’s minerals and chemicals, bacteria thrive. With waterless urinals, since there is no water involved, there is significantly less bacterial growth. The sealant in the urinal also prevents it from exposure to air, where bacteria can spread. Furthermore, flushing urinals can send water droplets into the air, which may spread bacteria throughout the bathroom and onto your hands or clothing [source: Waterless]. Waterless urinals don’t cause this issue.

However, like any other bathroom fixture, waterless urinals still need to be cleaned regularly to prevent bacteria from settling in and multiplying. Fortunately, cleaning them is simple: all you need is a household cleaner and a sponge or cloth to wipe down the exterior surfaces [source: Zero Flush].

7: How Much Water Do Traditional Urinals Use?

Waterless urinals are truly water-free. They don’t use a little water, they use none at all. Therefore, the water saved by installing one is roughly equal to the amount of water consumed by the urinal it replaces. Most traditional urinals use between 1 and 3 gallons (3.7 to 11.3 liters) of water per flush [source: Reichardt]. The range varies because older models tend to use more water, while newer ones are designed for greater efficiency. Urinals made in the 1990s and 2000s typically use 1 to 1.25 gallons per flush [source: Stumpf]. Some ultra-low-flow models consume even less. Older fixtures, however, can use up to 3 or gallons (11.3 to 13.2 liters) per flush [source: Stumpf]. The amount of water used also depends on the frequency of use. For example, a urinal in a busy office with over 100 employees will use more water than one in a small restaurant or gas station. With all factors considered, a single urinal in an office of several dozen workers can save around 45,000 gallons (170,000 liters) of water annually [source: Stumpf].

6: Waterless Urinals Easily Replace Traditional Models

The vast majority of waterless urinal manufacturers create their products to integrate seamlessly with conventional plumbing systems [source: Stumpf]. Many prominent manufacturers, such as Kohler and Sloan, even offer waterless toilet lines. This approach makes sense from a business perspective, as waterless urinals can already be a hard sell for some. These fixtures typically fit standard 2-inch drainage lines, though they can also be adapted to 1.5-inch lines [source: Waterless]. Since waterless urinals don’t require flushing, they don’t need to be connected to a second line for potable water supply.

If you've ever come across a waterless urinal, you might have spotted a pipe sticking out from the wall above it, seemingly without purpose. This pipe is actually the unused water supply line, which must be sealed off during the installation of waterless urinals when replacing traditional models. Since waste won't be flushed away by a fast-moving stream of water, the pipes leading from the urinals to the waste line must be sloped enough to allow for easy drainage. These pipes require a slope of at least a quarter inch per foot [source: Stumpf]. If the slope isn't adequate, the pipes will need to be adjusted, which may involve replacing a short section of piping that connects the urinal to the main waste line [source: Falcon].

5: Maintenance is Required

When compared to flushing urinals, waterless urinals demand less upkeep. Manufacturers often highlight in their marketing that their products are unlikely to leak and don’t have valves or handles that need replacement [source: Waterless]. While this is true, regular maintenance is still necessary to ensure proper functioning. For instance, the sealant liquid in the urinal needs to be replaced after around 1,500 uses, or about two to four times a year [source: Reichardt]. Over time, small amounts of the sealant are flushed away with the urine, causing the sealant levels to drop. Some models also feature removable trap cartridges. Depending on the brand, these cartridges need to either be cleaned or replaced. (Many companies will recycle the cartridges.) Sediment from urine can accumulate and clog the trap cartridges. For urinals that don’t feature removable cartridges, a plumbing snake will be required for cleaning when sediment buildup causes blockages [source: Stumpf].

4: Waterless Urinals Were Once Illegal

Waterless urinals were first introduced in 1991, but their widespread adoption didn’t take place until 2006. That year, the urinals were officially recognized as an alternative option under both the Uniform Plumbing Code and the International Plumbing Code [source: Davis]. These two codes are the foundation for most state and local plumbing regulations across the U.S. Following this pivotal decision, waterless urinals became legal in most parts of the country. Prior to this, only a few local governments had passed laws to make them legal. Initially, the plumbing industry was concerned that waterless urinals could be hazardous, particularly in terms of allowing harmful sewer gases to escape from drainage pipes. Once the technology was improved and it was shown that these urinals could be installed safely, states began revising their plumbing codes to permit their use [source: Davis].

3: The Price of Waterless Urinals

As we moved through the 2000s, waterless urinals gained traction, becoming a viable choice for businesses and public institutions aiming to conserve water [source: Davis]. These urinals are no longer a rare find, with many manufacturers now producing them in various styles and designs. The most affordable models start around $250 each [source: Reichardt], typically featuring a simple white design resembling traditional urinals. Higher-end models, often in designer colors or more sophisticated designs, can cost up to $1,000 [source: WaterWise Technologies]. In essence, waterless urinals are priced similarly to regular toilets. Some municipal water systems also offer rebates for installing these water-saving fixtures, which can range from $60 in Los Angeles to $400 per unit in San Diego County, among other locations [source: WaterWise Technologies].

2: Installing Waterless Urinals at Home

Waterless urinals can be installed in homes as well, allowing homeowners to reap the benefits typically enjoyed by large companies, like saving on utility bills and conserving water. A single urinal can save between 1 and 3 gallons of water per flush, and they are relatively affordable to buy and install. With two men in the household, a waterless urinal could save approximately 3,250 gallons (about 12,302 liters) of water annually [source: Wilson]. However, there is a key limitation to consider: only the men in the household can use it. Even if no women live in the home, you will still need to retain your regular toilet for other bathroom needs and for guests. Therefore, a waterless urinal should ideally be a supplementary fixture, and it’s important to ensure there is enough space for both fixtures in your bathroom.

1: Who Uses Waterless Urinals?

Thanks to their cost-effectiveness and water-saving properties, waterless urinals have gained significant traction among government organizations. For instance, the U.S. Army has required that all new military buildings be equipped with only waterless urinals starting in 2010 [source: Davis]. Many school districts and municipal government buildings are also adopting them. San Diego’s public schools, for example, have been using them since 1997 [source: San Diego Unified School District]. Waterless urinals also contribute to LEED certification points, making them popular with businesses and individuals looking to make their buildings more environmentally friendly. Notable venues like the L.A. Coliseum, the Georgia Aquarium, and even the Taj Mahal in India have transitioned to waterless urinals as well [sources: Georgia Aquarium, Cutraro].