Installing an aerator - a small piece of hardware you screw on to the tip of your sink's faucet - can be one of the most cost-effective water conservation measures you can take. Aerators cost about a dollar, and in most cases, take less than a minute to install. Be sure to look for the WaterSense label when replacing your aerator or installing a new bathroom faucet.
Many water providers give away low-flow aerators to their customers for free, or you can purchase one at most home improvement stores for less than $5.
According to WaterSense, a faucet that leaks at the rate of one drip per second can waste more than 3,000 gallons per year.