Water Conservation

Introduction

It is easy for some people in developed nations to take their water supply for granted. But water is essential to life and, according to the United Nations, one billion people around the world lack access to safe drinking water and 2.6 billion people lack adequate sanitation. Therefore, there is not enough water in circulation to even meet people’s basic needs. Added to this, agriculture and industry rely upon an adequate water supply for productivity. Therefore, water is a precious resource and its conservation is important.

There are many simple ways in which water can be conserved by the individual. Authorities, such as the U.S. Environmental Protection Agency (EPA), have various schemes to encourage a responsible attitude towards water consumption. Technical advances can aid water conservation, such as the low-volume toilet and new ways of irrigating crops. Water conservation, like energy efficiency, brings big benefits in terms of improving quality of life and protecting the environment.

Historical Background and Scientific Foundations

Forty-five countries around the world suffer from frequent water shortages, and in many other places drought can make water supplies uncertain. Much water is wasted though leaks in pipes, toilets, taps, and irrigation systems. Meanwhile, the growing world population and increasing industrialization increase the demand for freshwater. Without some kind of controlled reduction in this demand through water conservation, pressure on water supplies could have a widespread effect on human health and productivity.

Water conservation relies upon a mixture of behavioral change and technical advances. There are many simple ways in which individuals can save water, from fixing leaks and having shorter showers, to collecting and reusing water for the garden. Water conservation efforts should be driven by an awareness of which activities use the most water. Toilet flushing accounts for about 47% of typical household water use in the United States, followed by 31% for bathing, and 20% for laundry and dishwashing.

Therefore, low-volume toilets can make a difference to domestic water consumption. Prior to 1992, when these were introduced, a typical flush took six gallons of water but now it takes only 1.6 gallons. There are also water-efficient dishwashers and washing machines as well as low-volume shower heads. Wastewater can be reclaimed and recycled, with several cities now using purified sewage effluent. Agriculture is the greatest consumer of water worldwide and some practices are very wasteful. In standard irrigation, much water is lost through evaporation or runoff. But drip irrigation helps conserve water, by releasing controlled amounts of water just above plant roots, so that nearly all of the water is used by the plant.

Awareness of the need for water conservation is being increased by the water footprint concept, which has been developed by researchers at the University of Twente in the Netherlands. The water footprint can be applied to an individual, a business, or a nation, and it refers to the volume of water used in the production of goods and services used. For instance, it takes about 4,227 gallons (16,000 liters) of water to produce 2.2 pounds (1 kilogram) of beef, and 37 gallons (140 liters) of water to produce a cup of coffee.

Impacts and Issues

Wasting water not only makes shortages worse, it also contributes to water pollution. For example, diverting

WORDS TO KNOW

DRIP IRRIGATION: Slow, localized application of water just above the soil surface.

SEWAGE: Waste and wastewater discharged from domestic and commercial premises.

WATER FOOTPRINT: The total volume of water used to produce goods and services consumed by an individual, business or nation.

natural water supplies by building dams traps sediment, which concentrates pollutants and reduces dissolves oxygen. The more water people use, the more dirty wastewater is produced, which flows into natural water supplies, compromising their purity.

Water conservation improves the overall quality of the water supply and the environment in many ways. The sewage system is less liable to failure through overloading. More efficient irrigation means less polluted runoff from agricultural land. Natural pollution filters like wetlands are less likely to be dried up or depleted, while reduced need to build dams and reservoir preserves species’ habitats. Moreover, using less hot water means using less electricity, which benefits both the consumer and the environment.

See Also Drought; Industrial Water Use; Irrigation; Runoff; Water Resources; Water Supply and Demand

BIBLIOGRAPHY

Books

Cunningham, W.P., and A. Cunningham. Environmental Science: A Global Concern. New York: McGraw-Hill International Edition, 2008.

Web Sites

U.S. Environmental Protection Agency (EPA). “WaterSense®.” January 25, 2008. http://www.epa.gov/watersense/water/index.htm (accessed March 23, 3008).

Waterfootprint.org. “Water Footprint.” http://www.waterfootprint.org/?page=files/home (accessed March 23, 2008)