I read recently that the three biggest water wasters in the home are leaks and drips, toilets, and lawns. Now, I haven’t yet coughed up the bucks to replace all my toilets with the low flow variety (I’m working on it!), but I thought I had at least minimized the water waste, by adjusting the tank levels. Last week, I discovered another hidden water wasting feature built right into our toilets. Coming into the bathroom, I could hear the telltale sound of water slowly trickling. Being the resident Eco-Fascist (and, by majority vote, the home maintenance guy), I took the top off the tank and found that the valve was not quite turning off, so the water level was reaching the top of the fill pipe, continuing to slowly spill over into the bowl. No big deal, time to get a new fill valve assembly.
Off to the local home improvement store I went. I wasn’t surprised to see a multitude of choices and manufacturers, but I did discover there are newer types available now for about $6 more than the basic, familiar model. These newer types not only allow you to control the Tank Water Level, they have also added a valve that allows you to adjust the Bowl Water Level. I didn’t even know that was possible or necessary.
I’m assuming most of you know how to reduce water usage by adjusting the tank water level. Cool. But, according to the manufacturer, because of the way the refill mechanism works on a toilet, as much as 5 quarts of water can be wasted every time you flush due to overfilling of the bowl after the flush.
Here’s what I learned. In the photo, you can see that the bowl water level is determined by the height of the weir. The goal is to ensure there is a water seal between the outlet and the bowl so smells can’t come up through the trapway to the bowl. The problem with the standard water valves is that they are preset for the worst case (largest) size bowl to ensure the water level reaches the top of the weir.
The new style assemblies have an added adjustment to control the amount of water flowing to the bowl fill tube that tops off the bowl. The process is pretty simple. After flushing, you slowly add water to the bowl from a bucket until the water level in the bowl stops rising. (If you listen carefully you can hear the water spilling over the weir.)
After waiting a minute or two, take a pencil and mark a line about 1/8″ below the water level. Flush a few times, adjusting the bowl water level valve until the water only refills the bowl to the pencil line. Once set, you have an optimal water seal without allowing any water to spill over the weir.
There you have it! The average number of flushes per day is five per person. For our family of four, assuming we had the worst case scenario (5 quarts overflow), we have reduced our water usage by 25 gallons per day with the new valves installed, over 9,000 gallons per year.