Low flow showerheads (low-flo, low-flow) are an inexpensive way to save water.

It’s not just low flow, it’s the law. In 1995, the National Energy Policy Act mandated the use of toilets that use no more than 1.6 gallons of water per flush. Since then, low-flow plumbing fixtures including toilets, faucet aerators and showerheads have been developed that save substantial amounts of water compared to conventional fixtures while providing the same utility.
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Conventional faucet aerators don’t compensate for changes in inlet pressure, so the greater the water pressure, the more water you use. New technology compensates for pressure and provides the same flow regardless of pressure. Aerators are also available that allow water to be turned off at the aerator itself. Showerheads use similar aerator technology and multiple flow settings to save water.

Low Flow Plumbing Fixtures, from ToolBase
Numerous models are available, but one that we use and like is the Ultra Saver Showerhead (manufactured by Whedon Products model USB3C), which can be purchased for less than $10 at most hardware stores.

More

• WaterSense Showerheads – from the EPA
• American Water Works Association (AWWA)
• Water-Saving Tips – from AWWA
• Ways to Save Water – from the NYC Dept. of Environmental Protection
• Water Use It Wisely
• Low Flow Plumbing Fixtures – from ToolBase (NAHB)
• The Best Low-Flow Showerheads