2. Water: Using and Protecting Notes page 171

3. PEOPLE SETTLE NEAR WATER: Throughout history humans have settled near water sources such as springs, rivers, and lakes. These reliable fresh water sources have allowed civilizations to irrigate their crops and grow and prosper. As towns and cities grew, different methods were used to collect the water necessary to irrigate crops, run businesses, and keep people and livestock healthy. Some of these methods included tunnels, aqueducts, wells, cisterns, pumps, and reservoirs.

4. AGRICULTURE: Water is especially important in the areas of agriculture, power generation, and public health. Agricultural areas of the world rely heavily on the availability of fresh water. Reliable irrigation systems insure more productive crops and dependable harvests.

5. POWER GENERATION: Water is also used in power generation. Hydroelectric power plants use the kinetic energy of (1)moving water to produce electricity. In these plants, water is used to turn propeller-like turbines that power electric generators. Some hydroelectric plants use (2) steam instead of moving water to generate electricity. In these plants, water is heated to produce steam and the steam is used to turn the turbines.

6. PUBLIC HEALTH: Water is also important in the area of public health. Not too long ago, fresh water sources such as rivers and streams were used for drinking, cooking, bathing, washing clothes, watering livestock, and disposing of human wastes. As cities grew, open sewers that flowed to the nearest body of water were common. Fortunately, by the mid-1800s, public health officials began to realize that there might be a connection between contaminated water and outbreaks of disease. As a result, the development of sanitary sewers and advancements in water treatment methods over the last 150 years have helped to eliminate, or get rid of many diseases associated with contaminated or polluted water.

7. CLASSWORK / HOMEOWORK