1. Grace Masterjohn Sean Klapperich Autumn Kelley Amanda Lance

4. HOW WE USE WATER Where Does Our Water Go? Diverting Surface Water Using and removing dams Costs and benefits Dikes and levees Groundwater

5. WHERE DOES OUR WATER GO? Residential/Municipal: Drinking, cooking, and cleaning Agricultural: Irrigate crops and water for livestock. Industrial: Manufacturing processes Consumptive use: Take the water and don’t return it. Non-Consumptive use: We only temporarily use it. Ex: Hydroelectric dams

6. DIVERTING SURFACE WATER Water is diverted from rivers, streams, lakes, and ponds to provide water for farm fields, homes and cities. We are overexploiting surface water. Colorado River is a prime example of the depletion of our surface water.

7. USING AND REMOVING DAMS A dam is an obstruction placed in a river or stream. We build dams to prevent floods, provide drinking water, facilitate irrigation, and generate electricity. There are about 45,000 large dams (greater than 49 feet high) worldwide across rivers in over 140 nations. A concept introduced in the late 1990s, removing dams restores ecosystems and fisheries, and revives recreation.

9. BENEFITS AND COSTS OF DAMS BENEFITS COSTS Power generation Emissions reduction Crop irrigation Drinking water Flood control Shipping New recreational opportunities Habitat alteration Fisheries decline Population displacement Sediment capture Disruption of flooding Risk of failure Lost recreational opportunities

10. DIKES AND LEVEES Help prevent floods. They are long raised mounds of earth along the bank of rivers. Most of the time stops flooding, but can sometimes make flooding worse because they force water to stay in channels and accumulate lots of energy, leading to occasional catastrophic overflows.

11. GROUNDWATER Groundwater is extracted by drilling into the ground and using pipes to transport it. Most groundwater is being used faster than it can replenish itself. Artesian spring: Unconfined aquifer

12. We have altered many environmental systems. 60% of the worlds largest 277 rivers have been affected by artificial dams, canals, and diversions. Our consumption of fresh water is unsustainable. We are depleting many sources of surface and groundwater. 1/3 of the world’s people have already been affected by water scarcity as of 2006.

13. INEFFECTIVE IRRIGATION WASTES WATER 18% of the world farmland is irrigated but yields fully 40% of worlds agricultural produce, including 60% of the global grain crop. Only about 45% of the water we use for irrigations is actually taken up by crops. When floods are liberally flooded with water that may evaporate accounts for about 90% of irrigation worldwide. Can lead to waterlogging and salinization.

14. DEPLETING GROUND WATER More easily depleted than surface water because most aquifers recharge slowly. As aquifers are depleted, water tables drop. This will make groundwater more difficult and expensive to extract. When groundwater is over-pumped then salt water may intrude into aquifers.