Water Efficiency 101

Water efficiency is the long-term practice of conserving water resources through the employment of water-conserving technologies. Using water efficiently will conserve supplies for future generations.

Why Water Efficiency?

Across the nation, our growing population is putting stress on available water supplies. Between 1950 and 2000, the U.S. population nearly doubled. However, in that same period, public demand for water more than tripled! Americans now use an average of 100 gallons of water each day per person—enough to fill 1,600 drinking glasses! This increased demand has put additional stress on water supplies and distribution systems, threatening both human health and the environment.

There's a reason that water has become a national priority. A recent government survey showed at least 36 states are anticipating local, regional, or statewide water shortages by 2013. But by using water more efficiently, we can help preserve water supplies for future generations, save money, and protect the environment. 

How Do Americans Use Water?

Water is anessential ingredient for many aspects of daily life, from personal use to agricultural, industrial, and commercial needs. The amount of water used is usually defined in terms of withdrawal - water that is collected from the Earth's surface or extracted from ground water.

The four major categories of water users in the United States

Domestic

Water used for residential, commercial, industrial, and public uses such as street cleaning, fire fighting, municipal parks, and public swimming pools. This includes both publicly supplied sources (water delivered by a public or private system) and self-supplied sources (water withdrawn directly from surface or ground water, such as from privately owned wells). Fifteen percent of American households are self-supplied, while more than 240 million people depend on public supply systems. Withdrawals for public supply systems total more than 43 billion gallons per day. Historically, nearly 60 percent of the public supply is delivered to households. Self-supplied water to households totals nearly 4 billion gallons per day.

Power Plants

Water used during the production of energy from fossil fuels, nuclear, or geothermal sources. Most water withdrawn for power plants is used for cooling purposes; power plants use 136 billion gallons of fresh water per day.

Agricultural

Water used to irrigate farm crops and for livestock, dairies, feedlots, fish farms, and other farm needs. Agricultural irrigation accounts for more than 142 billion gallons of fresh water per day.

Industrial & Mining

Water used for cooling in factories and washing and rinsing in manufacturing processes. Some of the major water-use industries include mining, steel, paper, and associated products, as well as chemicals and associated products. Industrial facilities withdraw more than 20 billion gallons of fresh water per day.

What Are the Environmental Benefits of Water Efficiency?

Water efficiency, together with reducing pollutants such as pesticides, can be an effective way to reduce pollution caused by excessive watering and water use. Some of the environmental benefits that are aided by water efficiency include:

• Fewer sewage system failures caused from excess water overwhelming the system.
• Healthy, rather than depleted and dried up, natural pollution filters such as downstream wetlands.
• Reduced water contamination caused by polluted runoff due to overirrigating agricultural and urban lands.
• Reduced need to construct additional dams and reservoirs or otherwise regulate the natural flow of streams, thus preserving their free flow and retaining the value of stream and river systems as wildlife habitats and recreational areas.
• Reduced need to construct additional water and wastewater treatment facilities.
• Elimination of excessive surface water withdrawals that degrade habitat both in streams and on land adjacent to streams and lakes.

Efficient water use can also reduce the amount of energy needed to treat wastewater, resulting in less energy demand and, therefore, fewer harmful byproducts from power plants.

• Most people realize that hot water uses up energy, but supplying and treating cold water requires a significant amount of energy too. American public water supply and treatment facilities consume about 56 billion kilowatt-hours per year—enough electricity to power more than 5 million homes for an entire year.
• If just 1 percent of American homes replaced an older toilet with a new WaterSense labeled toilet, the country would save more than 38 million kilowatt-hours of electricity—enough electricity to supply more than 43,000 households for one month.
• Letting your faucet run for five minutes uses about as much energy as letting a 60-watt light bulb run for 14 hours.

Other Benefits of Water Efficiency

Money Savings

The average household spends as much as $500 per year on its water and sewer bill. By making just a few simple changes to use water more efficiently, you could save about $170 per year. If all U.S. households installed water-efficient appliances, the country would save more than 3 trillion gallons of water and more than $18 billion dollars per year! Also, when we use water more efficiently, we reduce the need for costly water supply infrastructure investments and new wastewater treatment facilities. 

Water Efficiency, Human Health, and the Environment

Depleting reservoirs and groundwater aquifers can put water supplies, human health, and the environment at serious risk. Lower water levels can lead to higher concentrations of natural contaminants, such as radon and arsenic, or human pollutants, such as agricultural and chemical wastes. Using water more efficiently helps maintain supplies at safe levels, protecting human health and the environment.

Source: Environmental Protection Agency (EPA)