Americans use more water per person than citizens of any other country. According to the EPA, the average American family uses more than 300 gallons of water per day at home. Around 70 percent of this use occurs indoors with cooking, cleaning, and bathing. A source of great confusion for many is with just how much water is in American toilets. Many visitors from all over the world — Europe, in particular — feel toilets in America have too much water. For some, American toilet water level has even become a tourist attraction. So, why do American toilets have so much water?
Toilet Flush System
Europeans use the washdown flush system, where the water’s weight and gravitational force push the waste product down to the sewer system or a rural septic system.
Americans, on the other hand, use a different approach. Toilets in the United States have a long and narrow reverse ‘S’ or ‘P’ trap with one end connected to the toilet bowl and the other to the drain pipe.
This design creates a siphoning action, ‘sucking’ out the water along with the waste when the toilet is flushed.
When you flush the American toilet, the water siphons over the trap to clean the toilet, and then the inflow water fills it.
This approach is known as a Siphonic flushing system. In other words, the water level in American toilets is a function of the elevation of the built-in p-trap in the toilet bowl construction.
American Toilets Need More Water to Flush
Another reason American toilets have so much water is that they need more water to flush effectively. That’s just how they are designed. Toilets in Europe rely on the gravitational force of water from the cistern to flush away the contents.
On the other hand, toilets in the United States’ suck’ the waste away using a partial vacuum created by the bowl’s siphon system.
The latter needs more water in the bowl to function correctly. The idea is to get the water to cover the platform and basically wash away the waste in the same way tides drag stuff off the beach.
And siphon-toilet bowls aren’t restricted to the United States. You can also find these toilet designs in European countries — though they are not very common — and they will have higher levels of water just like the ones in the US.
As you can see, the higher level of water in American toilets compared to toilets in Europe and other parts of the world boils down to technical design. Americans and Europeans use different approaches when it comes to toilet flushing systems. The American approach requires more water to flush.
In other words, the high level of water in American toilets is by design. This is to ensure that the toilet is clean after use. In Europe, the water level in the toilet is lower and counts on the user cleaning out the bowl after use.
Most people in the United States just aren’t comfortable doing that. We hope we have answered the question, “why do American toilets have so much water”?