Stretching the Water Supply: The Importance of Water Efficiency Measures

Friday, January 19, 2024

Although water covers 70% of the earth’s surface, only 1 percent is available for human use. While freshwater supplies remain relatively finite, demand for water in the United States has tripled over the past 50 years. Population growth and climate change are expected to exacerbate stress to water supply and quality. With many states already experiencing water shortages, using water efficiently is paramount to adapting to climate change and maintaining reliable water supplies today and in the future. 

In the United States, residences use more than half of publicly supplied water, with each American using an average of 82 gallons of water in their home each day. Flushing the toilet is the largest culprit—accounting for 24% of indoor water use, followed by showers, faucets, clothes washers, bathtubs, and dishwashers. By installing WaterSense efficient fixtures and appliances, Americans can use at least 20% less water and save on water costs. By replacing inefficient toilets with WaterSense labeled models, for example, the average family can reduce water usage by 20–60% and save more than $140 in water costs per year. In addition to indoor use, Americans use an estimated 8 billion gallons of water each day outdoors, mainly for landscape irrigation. Water-smart landscape strategies, including growing native and low water-using plants, and using water efficient irrigation controllers, can help Americans maintain healthier and less-wasteful landscapes. The Alliance for Water Efficiency (AWE) offers additional water saving tips for residences to help families save water and lower water bills.  

Water efficiency measures also deliver significant energy savings, since the water that we use every day requires energy to be pumped, treated, distributed to residences, heated, collected, and treated again before discharge. According to a 2017 Congressional Research Service Report, 30–40% of municipal energy bills can be attributed to energy consumption by public drinking water and wastewater utilities, the majority of which are owned and operated by local governments. Given that drinking water and wastewater systems contribute to 45 million tons of greenhouse gas emissions annually, using water more efficiently also can help to mitigate climate change through emissions reduction. 

This “water-energy nexus” was first recognized at the federal level by the landmark Energy Policy Act of 1992, which mandated more energy and water efficient plumbing fixtures, including toilets, showerheads, urinals, and faucets. In 2014, AWE found that the legislation had saved 18.2 trillion gallons of water nationwide by updating efficiency standards for toilets, enough water to supply the cities of Los Angeles, Chicago, and New York with water for 20 years. And that was just toilets. Federal standards now exist for plumbing fixtures, clothes washers, dishwashers, and other water-using devices.

In addition to federal standards, water efficiency policies are made primarily at the local and state levels. The AWE and ELI 2022 State Policy Scorecard for Water Efficiency and Sustainability provides a ranking of U.S. states based on their adoption and implementation of state-level policies that advance water efficiency, conservation, sustainability, and affordability. The Scorecard also outlines recommendations for each state and identifies existing successful policies. With states scoring an average of 23 out of 89 possible points, the United States has progress to make on water efficiency measures to ensure safe, reliable, and resilient water supplies. 

This post was created in conjunction with People Places Planet Podcast episode Every Drop Counts: At the Confluence of Water and Law. 

Additional resources mentioned in the episode include: 
•    Net Blue Ordinance Toolkit to support sustainable community growth. 
•    Water and Planning Network a professional forum for planners focused on water issues in their communities. Email to join.