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

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

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://svs.gsfc.nasa.gov/vis/a010000/a010000/a010057/

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 1.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. Two Important characteristics of all Watersheds are: About Watersheds

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

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 Figure 14-1 UNICEF - Somalia - Conflict over scarce resources in drought-stricken Somalia http://www.unicef.org/infobycountry/somalia_34070.html

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 1/6 th ) of the worlds population does not have access to a clean, reliable source of drinking water!

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

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. Figure 14-11 Saltwater intrusion into drinking water supplies near coastal areas

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

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. Fig. 14-13a, p. 317 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

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

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 (1/10 th 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. Fig. 14-14, p. 318 Dam Aqueduct or canal Upper Basin LOWER BASIN 0100 mi. 0150 km Lower Basin UPPER BASIN IDAHO WYOMING Salt Lake City Grand Junction Denver UTAH NEVADA COLORADO Lake Powell Las Vegas Grand Canyon Glen Canyon Dam Boulder City NEW MEXICO ARIZONA Los Angeles Albuquerque Phoenix San Diego Mexicali Yuma Tucson All-American Canal Gulf of California MEXICO CALIFORNIA Palm Springs Colorado River

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. 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 http://news.nationalgeographic.com/news/2007/11/071127-dam-video-ap.html

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

42. Lake Chad in Africa 1972 1987

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%.

51. Center pivot Drip irrigation Gravity flow (efficiency 60% and 80% with surge valves) Above- or below- ground pipes or tubes deliver water to individual plant roots. Water usually comes from an aqueduct system or a nearby river. (efficiency 90–95%) (efficiency 80%–95%) Water usually pumped from underground and sprayed from mobile boom with sprinklers.

52. Fig. 14-21, p. 327 Solutions Reducing Water Waste Redesign manufacturing processes Repair leaking underground pipes Landscape yards with plants that require little water Use drip irrigation Fix water leaks Use water meters Raise water prices Use waterless composting toilets Require water conservation in water- short cities Use water-saving toilets, showerheads, and front loading clothes washers Collect and reuse household water to irrigate lawns and nonedible plants Purify and reuse water for houses, apartments, and office buildings Don't waste energy

53. Raising the Price of Water: A Key to Water Conservation We can reduce water use and waste by raising the price of water while providing low lifeline rates for the poor. –When Boulder, Colorado introduced water meters, water use per person dropped by 40%. –A 10% increase in water prices cuts domestic water use by 3-7%.

54. Solutions: Using Less Water to Remove Industrial and Household Wastes We can mimic the way nature deals with wastes instead of using large amounts of high-quality water to wash away and dilute industrial and animal wastes. –Use nutrients in wastewater before treatment as soil fertilizer. –Use waterless and odorless composting toilets that convert human fecal matter into a small amount of soil material.

55. TOO MUCH WATER Heavy rainfall, rapid snowmelt, removal of vegetation, and destruction of wetlands cause flooding. Floodplains, which usually include highly productive wetlands, help provide natural flood and erosion control, maintain high water quality, and recharge groundwater. To minimize floods, rivers have been narrowed with levees and walls, and dammed to store water. ****This causes excess sediment to build up in estuaries and deltas and can eventually turn an estuary into a meadow.

56. Fig. 14-23a, p. 330 Oxygen released by vegetation Diverse ecological habitat Evapotranspiration Trees reduce soil erosion from heavy rain and wind Agricultural land Steady river flow Leaf litter improves soil fertility Tree roots stabilize soil and aid water flow Vegetation releases water slowly and reduces flooding Forested Hillside

57. Fig. 14-23b, p. 330 Tree plantation Roads destabilize hillsides Evapotranspiration decreases Ranching accelerates soil erosion by water and wind Winds remove fragile topsoil Agricultural land is flooded and silted up Gullies and landslides Heavy rain leaches nutrients from soil and erodes topsoil Silt from erosion blocks rivers and reservoirs and causes flooding downstream Rapid runoff causes flooding After Deforestation

58. SOLUTIONS: USING WATER MORE SUSTAINABLY We can use water more sustainably by cutting waste, raising water prices, preserving forests and wetlands in water basins, and slowing population growth. Figure 14-25

59. Fig. 14-25, p. 333 What Can You Do? Water Use and Waste Use water-saving toilets, showerheads, and faucet aerators. Shower instead of taking baths, and take short showers. Stop water leaks. Turn off sink faucets while brushing teeth, shaving, or washing. Flush toilets only when necessary. Wash only full loads of clothes or use the lowest water-level for smaller loads. Use recycled (gray) water for lawn, gardens, house plants, car washing. Wash a car from a bucket of soapy water, and use the hose for rinsing only. If you use a commercial car wash, try to find one that recycles its water. Replace your lawn with native plants that need little if any watering and decorative gravel or rocks. Water lawns and gardens in the early morning or evening. Sweep or blow off driveways instead of hosing off with water. Use drip irrigation and mulch for gardens and flowerbeds.