Save 10 Gallons of Water with a Brick in the Toilet

The old folk wisdom that says place a brick in your toilet’s water tank is partially correct: It’s an effortless way to save water, but a brick isn’t the best choice of object. Use a plastic bottle filled with water instead.

Don’t worry, you don’t have to turn hippie and “let it mellow if it’s yellow” in order to save clean water — which is an increasingly scarce resource. Most toilets will flush perfectly well with a little less H₂O. The average model uses three to seven gallons per flush. A bottle in the tank will displace enough water to save half a gallon to a gallon each use, or up to about 10 gallons a day in a typical home.

All you have to do is drop a little sand or some pebbles into a bottle, fill it with water, and put it in the tank, making sure not to disturb the toilet’s working parts. Many toilets flush well with a submerged 2-liter soda bottle, but experiment to find out what size bottles fit best and produce the best flush.

What’s wrong with a brick? They have been known to disintegrate in toilet water over time, leading to damaged plumbing. If you are a mason or otherwise determined to use a brick, wrap it in a sturdy plastic bag first.

You can also look for kits at local home improvement stores to convert American-style flushers to European-style dual-flushers, offering a half-flush option for liquids ($20 at homedepot.com). When it comes time for a new toilet, look for one with a WaterSense label. And, of course, be sure to fix leaks, which can cost $20 or more in wasted water.