You never miss the water til the well runs dry!

1. You never miss the water til the well runs dry!

2. WATER, WATER Everywhere……… Water keeps us alive, moderates climate, sculpts the land, removes and dilutes wastes and pollutants, and moves continually through the hydrologic cycle.

3. Global Water Distribution (Which means only 1% Of Earth's water is Available to us as liquid fresh water!!!!!)

4. As you know, most of the Earth’s fresh water is tied up in ice bergs in the north and south poles.

5. The water cycle The EPA Climate Change Kids Page--Water Cycle Animation http://www.sweetwater.org/education/watercycle.swf

6. Surface water (Provides: drinking water, water for crops, food, transportation, Power, fishing, industry, household use etc) Lakes

7. Rivers

8. Streams

9. Wetlands

10. River systems and Watersheds A watershed is the area of land that drains into a river. The Miss- issippi River basin is the largest watershed in the US. (What’s the largest river system in the world???) http://interactive-earth.com/visualizations/jela/2-mississippi-watershed-v2.2.html

11. Watersheds provide us with food, recreation, transportation, irrigation and industrial opportunities. They also provide us with a water source that eventually becomes our "clean water." Hence, watersheds are important to our health, our environment, our economy and our overall existence Two Important characteristics of all Watersheds are: About Watersheds • They collect and move precipitation from higher to lower elevations, eventually moving water to a larger river or body of water. 2. As rainwater washes over the land, the runoff picks up pollutants such as oil, grease, fertilizers, pesticides, trash and dirt. These pollutants eventually find their way into rivers, bays, wetlands, oceans and groundwater.

13. Groundwater As you know, surface water percolates through the ground to become groundwater! Groundwater - flash animated diagram The Groundwater Story Animation

14. Aquifers can take thousands of years to recharge, so it Is very important that the surface of the recharge zone Is PERMEABLE! Aquifer water is hard to clean once it gets polluted, cause the water collects in the sand and the rocks

15. Core Case Study: Water Conflicts in the Middle East - A Preview of the Future • Many countries in the Middle East, which has one of the world’s highest population growth rates, face water shortages. • Many countries lack cooperative agreements http://www.unicef.org/infobycountry/somalia_34070.html UNICEF - Somalia - Conflict over scarce resources in drought-stricken Somalia Figure 14-1

16. WATER’S IMPORTANCE, AVAILABILITY, AND RENEWAL • Irrigation is the biggest user of water (70%), followed by industries (20%) and cities and residences (10%).

17. Global Water Use

18. Water use and Management Well, around 1 billion people (yes 1/6th) of the worlds population does not have access to a clean, reliable source of drinking water!

19. Residential Water Use In the US, the average Person uses 300L (80) Gallons of water per day. In India average use is 41 L per day.

20. Industrial Water Use -Used to manufacture goods. For example 500,000 liters Of water is used to manufacture one car. -Used in nuclear power plants to cool the plant. River or ocean water is generally pumped in to cool reactors then it’s put back into the river. This leads to thermal pollution. (Remember what happens to DO when the temp goes up?) -Also used to dispose of wastes. For example when computer chips are manufactured, the waste water that has lots of chemicals in it is treated and then put into water treatment Facilities for further treatment.

21. Agricultural Water Use Water diversion projects have been used for thousands of years to establish societies where water was not plentiful. Irrigation is the diversion of water to grow plants where the soil is fertile but the areas natural precipitation is not sufficient to sustain the crops.

22. Unfortunately, as much as 80% of the water used in irrigation evaporates and never reaches the plants roots. It takes 80 gal of water (300 L) to produce one ear of corn.

23. TOO LITTLE FRESHWATER • Our water options are: • Get more water from aquifers and rivers, desalinate ocean water, waste less water.

24. WITHDRAWING GROUNDWATER TO INCREASE SUPPLIES • Most aquifers are renewable resources unless water is removed faster than it is replenished or if they are contaminated. • Groundwater depletion is a growing problem mostly from irrigation. • At least one-fourth of the farms in India are being irrigated from overpumped aquifers.

25. Groundwater Depletion: A Growing Problem • The Ogallala, the world’s largest aquifer, is most of the red area in the center (Midwest). • Areas of greatest aquifer depletion from groundwater overdraft in the continental U.S. Figure 14-8

26. Other Effects of Groundwater Overpumping • Groundwater overpumping can cause land to sink, and contaminate freshwater aquifers near coastal areas with saltwater. Saltwater intrusion into drinking water supplies near coastal areas Figure 14-11

27. Major irrigation well Well contaminated with saltwater Water table Sea level Fresh groundwater aquifer Saltwater Seafloor Interface Saltwater intrusion Interface Normal interface Fig. 14-11, p. 315

28. Other Effects of Groundwater Overpumping • Sinkholes form when the roof of an underground cavern collapses after being drained of groundwater. • Solutions: • Waste less • Grow more drought resistant crops • Subsidize water conservation • Raise the price of water • Set and enforce minimum stream flows Figure 14-10

29. USING DAMS AND RESERVOIRS TO SUPPLY MORE WATER • Large dams and reservoirs can produce cheap electricity, reduce downstream flooding, and provide year-round water for irrigating cropland, but they also displace people and disrupt aquatic systems.

30. Provides water for year-round irrigation of cropland Flooded land destroys forests or cropland and displaces people Large losses of water through evaporation Provides water for drinking Downstream cropland and estuaries are deprived of nutrient-rich silt Reservoir is useful for recreation and fishing Risk of failure and devastating downstream flooding Can produce cheap electricity (hydropower) Downstream flooding is reduced Migration and spawning of some fish are disrupted Fig. 14-13a, p. 317

31. Powerlines Reservoir Dam Powerhouse Intake Turbine Fig. 14-13b, p. 317

32. Case Study: The Colorado Basin – an Overtapped Resource • The Colorado River has so many dams and withdrawals that it often does not reach the ocean. • 14 major dams and reservoirs, and canals. • Water is mostly used in desert area of the U.S. • Provides electricity from hydroelectric plants for 30 million people (1/10th of the U.S. population). colorado

33. Case Study: The Colorado Basin – an Overtapped Resource • Lake Powell, is the second largest reservoir in the U.S. • It hosts one of the hydroelectric plants located on the Colorado River. Figure 14-15

34. The Colorado River Basin • The area drained by this basin is equal to more than one-twelfth of the land area of the lower 48 states. Figure 14-14

35. IDAHO WYOMING Dam Aqueduct or canal Salt Lake City Upper Basin Denver Grand Junction Lower Basin UPPER BASIN UTAH Colorado River NEVADA Lake Powell COLORADO Grand Canyon Glen Canyon Dam Las Vegas NEW MEXICO Boulder City CALIFORNIA Los Angeles ARIZONA Albuquerque LOWER BASIN Palm Springs 0 100 mi. Phoenix San Diego Yuma 0 150 km Tucson Mexicali All-American Canal MEXICO Gulf of California Fig. 14-14, p. 318

36. How Would You Vote? • Do the advantages of large dams outweigh their disadvantages? • a. No. Large dams inflict extensive environmental damage and humans must learn to meet their needs without them. • b. Yes. Dams are critical in providing water and electricity for people, especially in developing countries.

37. http://news.nationalgeographic.com/news/2007/11/071127-dam-video-ap.htmlhttp://news.nationalgeographic.com/news/2007/11/071127-dam-video-ap.html Case Study: China’s Three Gorges Dam • There is a debate over whether the advantages of the world’s largest dam and reservoir will outweigh its disadvantages. • The dam will be 2 kilometers long. • The electric output will be that of 18 large coal-burning or nuclear power plants. • It will facilitate ship travel reducing transportation costs. • Dam will displace 1.2 million people. • Dam is built over seismatic fault and already has small cracks. http://videos.howstuffworks.com/discovery/7143-china-three-gorges-dam-video.htm

38. Dam Removal • Some dams are being removed for ecological reasons and because they have outlived their usefulness. • In 1998 the U.S. Army Corps of Engineers announced that it would no longer build large dams and diversion projects in the U.S. • The Federal Energy Regulatory Commission has approved the removal of nearly 500 dams. • Removing dams can reestablish ecosystems, but can also re-release toxicants into the environment.

39. TRANSFERRING WATER FROM ONE PLACE TO ANOTHER • Transferring water can make unproductive areas more productive but can cause environmental harm. • Promotes investment, jobs and strong economy. • It encourages unsustainable use of water in areas water is not naturally supplied.

40. Case Study: The California Experience • A massive transfer of water from water-rich northern California to water-poor southern California is controversial. Figure 14-16

41. CALIFORNIA NEVADA Shasta Lake UTAH Sacramento River Oroville Dam and Reservoir Feather River North Bay Aqueduct Lake Tahoe Sacramento San Francisco Hoover Dam and Reservoir (Lake Mead) South Bay Aqueduct Fresno San Joaquin Valley San Luis Dam and Reservoir Colorado River Los Angeles Aqueduct ARIZONA California Aqueduct Colorado River Aqueduct Central Arizona Project Santa Barbara Los Angeles Salton Sea San Diego Phoenix Tucson MEXICO Fig. 14-16, p. 321

42. Lake Chad in Africa 1987 1972

43. MONO LAKE

44. Case Study: The Aral Sea Disaster • The Aral Sea was once the world’s fourth largest freshwater lake. Figure 14-17

45. http://liveearth.org/en/liveearthblog/death-aral-sea

46. Case Study: The Aral Sea Disaster • Diverting water from the Aral Sea and its two feeder rivers mostly for irrigation has created a major ecological, economic, and health disaster. • About 85% of the wetlands have been eliminated and roughly 50% of the local bird and mammal species have disappeared. • Since 1961, the sea’s salinity has tripled and the water has dropped by 22 meters most likely causing 20 of the 24 native fish species to go extinct.

47. DESALTING SEAWATER, SEEDING CLOUDS, AND TOWING ICEBERGS AND GIANT BAGGIES • Removing salt from seawater by current methods is expensive and produces large amounts of salty wastewater that must be disposed of safely. • Distillation: aka DESALINATION,heating saltwater until it evaporates, leaves behind water in solid form. • Reverse osmosis: uses high pressure to force saltwater through a membrane filter.

48. DESALTING SEAWATER, SEEDING CLOUDS, AND TOWING ICEBERGS AND GIANT BAGGIES • Seeding clouds with tiny particles of chemicals to increase rainfall towing icebergs or huge bags filled with freshwater to dry coastal areas have all been proposed but are unlikely to provide significant amounts of freshwater.

49. INCREASING WATER SUPPLIES BY WASTING LESS WATER • We waste about two-thirds of the water we use, but we could cut this waste to 15%. • 65-70% of the water people use throughout the world is lost through evaporation, leaks, and other losses. • Water is underpriced through government subsidies. • The lack of government subsidies for improving the efficiency of water use contributes to water waste.

50. INCREASING WATER SUPPLIES BY WASTING LESS WATER • Sixty percent of the world’s irrigation water is currently wasted, but improved irrigation techniques could cut this waste to 5-20%. • Center-pivot, low pressure sprinklers sprays water directly onto crop. • It allows 80% of water to reach crop. • Has reduced depletion of Ogallala aquifer in Texas High Plains by 30%.