According to the EPA, each household uses about 30 gallons (133.6 liters)of water for showering each day [source: Environmental Protection Agency], totaling nearly 11,000 gallons (41,639.5 liters) per year. Low-flow showerheads, which flow at a rate of less than the 2 gallons (7.6 liters) per minute with a water pressure of 80 pounds per square inch, can cut water consumption by up to 60 percent [source: U.S. Department of Energy]. Reducing consumption limits the amount of energy devoted to heating that water, as well, which could save you up to 300 kilowatt hours of energy each year [source: EPA]. New low-flow showerheads generally cost less than $20.
By law, new standard-flow showerheads can't exceed 2.5 gallons (9.5 liters) per minute with a water pressure of 80 pounds per square inch, but some older models flow at more than twice this rate. Here's a simple test recommended by the Department of Energy to figure out if you should swap out your shower head: Use a bucket marked in gallon increments and put it under your showerhead. If it takes less than 20 seconds to fill the bucket, you would save money by installing a new shower head [source: U.S. Department of Energy].