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1.1 Introduction

Water covers about 71% of the earth's surface equal to 326 million cubic miles of
water on the planet. While 97% of Earth's water is found in the oceans (too salty for
drinking, growing crops, and most industrial uses except for cooling), equivalent to
about 320 million cubic miles of water in the oceans, there is roughly 3% of Earth's
water is fresh, as 2.5% Of Earth's freshwater is not available: trapped in glaciers,
polar ice caps, the atmosphere, and soil; Highly polluted or located too far below the
earth's surface for affordable extraction, and about 0.5% of the Earth's water is
available from freshwater.

Fieger 1-1 Water percentages on Earth

As the current water problems are attributed to these reasons:

1. The lack of precipitation has negative effects on the amount of surface water.

Climate changes have reduced precipitation.

2. Rapid population growth leads to massive exploitation of aquifers and pollution
of water supplies.

3. Global warming , high temperatures lead to dehydrate a lot of drinkable water .

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