Students know that the amount of fresh water located in rivers, lakes, underground sources, and glaciers is limited and that its availability cna be extended by recycling and decreasing the use of water.

The vast majority of the Earth’s water is in the form of salt water. Fresh water makes up only 3% of the water found on Earth. Only one-third of this fresh water is actually available for use by plants and animals. The rest is frozen within Earth’s glaciers and icecaps, primarily located in the polar regions. Thus, only 1% of Earth’s water is available as fresh water that flows through our world’s rivers, lakes, reservoirs, and underground aquifers. This water supplies the pipes of our homes, businesses, and farms.

This limited fresh water supply is not evenly distributed throughout the world, and this unequal distribution applies to California as well. Most Californians live in areas that do not have enough fresh water locally to meet current and future uses. One way to tackle the problem of an inadequate local water supply is to import water from the northern part of the state where most of the rain and snow falls each year. However, this can only be part of the solution. We must all reduce the amount of water we use each day, whether it be in the home, school, farm, business, or industry.

Any attempt to reduce water use is known as water conservation. Personal water use in the U.S. averages 150 gallons per person per day. Most people know that they can save water by taking shorter showers or by turning off the water while they brush their teeth. These kinds of lifestyle changes combined with home improvements (e.g., low-flow shower heads and faucets, water-efficient clothes and dish washers, etc.) can provide significant water savings.

Lawns and gardens account for 30 to 70% of the water used directly in homes. Families with lawns and/or gardens can save large amounts of water by repairing leaks, watering the minimal amount and at the right time of day, or by planting native plants that don’t require watering.

To learn more about water conservation at home, visit these helpful websites:

Home Water Conservation Tips
www.H2OUSE.org

Be Water Wise
www.bewaterwise.com

Earth 911 – put in your zip code to find local information
www.earth911.org/

WaterWiser Drip Calculator
http://www.awwa.org/advocacy/learn/conserve/dripcalc.cfm

Most texts and public service messages emphasize water conservation in the home. While this is very important, in California in 2001, irrigation accounted for about 40% of the water withdrawn for human use. Irrigation is the process of supplying water to agricultural lands when there is not enough rainfall. The world’s farms could not supply the food needed to support 6 billion people without irrigation of croplands.

There are two major ways that water conservation can reduce the amount of water used for irrigation: more efficient irrigation techniques and use of recycled water. Water recycling takes wastewater that has been treated so that is clean and safe (though not up to drinking water standards) and uses it to irrigate farms, schools, parks, sports fields and commercial landscaping. Water recycling is practiced worldwide, and California has been a pioneer in water recycling for over 50 years. In fact, recycled water is the fastest growing water supply in California. Citizens can encourage government and the agriculture industry to practice rigorous water conservation in irrigation.

You can learn more about irrigation at http://ga.water.usgs.gov/edu/wuir.html.

We use almost as much water for generating energy as we do for irrigating land. Producing electricity generates lots of heat, and large amounts of water are needed to cool the power-producing equipment. This water must also be cooled before it is released back into the environment. We can reduce the amount of water needed for generating electricity by reducing the energy we use at home and at work.

To learn even more about water use in the United States, visit the United States Geologic Survey’s Water Science for Schools website at http://ga.water.usgs.gov/edu/index.html