Water is a vital natural resource that all living things need to survive. Earth's extensive oceans hold 97 percent of our water supply in the form of salt water. Much of the other 3 percent — the freshwater — is trapped in polar ice caps and glaciers. What remains — just 1 percent of the overall total — is found in natural underground storehouses called aquifers and in surface lakes and streams.

According to the 2000 U.S. Geological Survey figures, of the more than 400 billion gallons (1.5 trillion liters) of water removed from all sources each day in the U.S. alone, about 85 percent comes from freshwater sources. Nearly 40 percent of the freshwater is used for thermoelectric power generation. Another 40 percent goes toward irrigation to sustain agriculture. The remaining freshwater withdrawals go, in descending order, toward public water supplies (e.g., public buildings, pools, and firefighting needs), industrial use, and domestic use.

While water is a renewable resource that can be replenished through the water cycle and by wastewater treatment facilities, humans are using it at a faster rate than it is being replenished. The demands of growing populations and expanding industries have put a strain on freshwater ecosystems and are causing water shortages in many parts of the world.

To prevent further shortages, households, communities, and private industries can adopt water-saving practices. Homeowners can save water by fixing leaks or dripping taps. Although the water lost from leaks may not seem like much, it amounts to a tremendous waste when you consider how often this can happen across a large population. Homes can also be fitted with low-flow devices — such as showerheads and toilets — that are designed to use less water.

Communities can help conserve water by trying to limit sprawl, a term used to describe development occurring further and further outside of a city center. Sprawl necessitates additional diversion of water from city supplies to serve suburban community needs. Also, because agriculture uses such a large percentage of available water, developing conservation-minded irrigation practices can conserve a considerable amount of water. For example, farmers can utilize recycled "gray water," as described in the video segment, and/or plant drought-resistant crops.

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