Faucets:The aerator--the screw-on tip of the faucet--ultimately determines the maximum flow rate of a faucet. Aerators are inexpensive to replace and they can be one of the most cost-effective water conservation measures. For maximum water efficiency, purchase aerators that have flow rates of no more than 1.0 gpm. Some aerators even come with shut-off valves that allow you to stop the flow of water without affecting the temperature. When replacing an aerator, bring the one you're replacing to the store with you to ensure a proper fit.

Shower heads: For maximum water efficiency, select a shower head with a flow rate of less than 2.5 gpm (flow rate is noted on the packaging). There are two basic types of low-flow shower heads: aerating and laminar-flow. Aerating shower heads mix air with water, forming a misty spray. Laminar-flow shower heads form individual streams of water. If you live in a humid climate, you might want to use a laminar-flow shower head because it won't create as much steam and moisture as an aerating one.

If you have fixtures that pre-date 1992, many of which are not water-conserving, consider this quick test:

Place a bucket--marked in gallon increments--under your shower head.
Turn on the shower at the normal water pressure you use.
Time how many seconds it takes to fill the bucket to the 1-gallon (3.8 liter) mark.

If it takes less than 20 seconds to reach the 1-gallon mark, you could benefit from a low-flow shower head.