Water covers three-quarters of the Earth’s surface. This water is the only water that will ever be available to the planet. However, only a fraction of this water is usable fresh water, since 97% of the Earth’s water is salt water. Another 2% of fresh water is stored in glaciers, ice caps, and on top of snowy mountains. The remaining 1% is the Earth’s daily water supply. This fresh water is found underground and in lakes, rivers, and streams.
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Fresh water is used for a variety of purposes. About 42% of fresh water is used for agriculture. Another 39% is used for the production of hydroelectricity, 11% is used for homes, offices, and hotels, and the remaining 8% is used for manufacturing and mining. It is so important to keep this fresh water clean. Humans are responsible for releasing often harmful chemicals and substances into the water system. In 1972,Congress passed the Clean Water Act, which stared national conservation efforts to clean up our nation’s waters. With an ever growing population, water quality and quantity is a major concern.
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