More efficient faucets exist too. Piscataway, N.J.-based American Standard now offers FloWise, a showerhead line with a dual-function feature that allows users to choose a 2.5- or 1.5 gallons-per-minute flow rate. Other manufacturers, including Kohler and Grohe, also make faucets with reduced water output.

Even the best faucets and most efficient heaters can't prevent waste while users wait for the water to reach their desired temperature, however. Cherokee Investment Partners found a solution to this problem when specing its Mainstream GreenHome: the Metlund Hot Water D'MAND System. Manufactured by Costa Mesa, Calif.-based ACT, Inc. Metlund Systems, the D'MAND recirculates ambient-temperature water so hot water is virtually instant and little is wasted down the drain.

drops in the bucket

The EPA says the nation's population doubled from 1950 to 2000, and during that same time period, public demand for water more than tripled. The American Water Works Association reports that the average single-family household uses 70 gallons of water per day. Factor in water usage for landscaping, and the severity of the problem is magnified.

State and regional officials routinely employ temporary restrictions when water is in short supply, but green advocates believe such limits may become permanent as the stakes rise and as interest in sustainable building continues to grow. “I think municipalities and states will start implementing restrictions year-round,” rather than simply during periods of drought, says Chris Miles, principal of GreenCraft Builders in Lewisville, Texas. “You're going to see a major shift in water attitudes.” Already, county supervisors in Stafford, Va., are eyeing a plan that would restrict water use from May 1 to Oct. 31 every year and could permanently limit which days residents can water their lawns each summer.

Architects and developers can help the cause by adding water-conserving design features to their projects; by specing energy-efficient appliances, faucets, and fixtures; and by designing simple, affordable water-collection systems. As the EPA's WaterSense program notes: every drop counts.