1. Chapter 13
WATER RESOURCES

2. Case Study: Water Conflicts in the Middle East
The water from the Nile River is used by three countries: Ethiopia, Sudan, and Egypt. Since Ethiopia’s population is rapidly increasing, they plan to divert more water from the Nile, along with Sudan.
The Jordan basin is the most water short region and has competition between Jordan, Syria, Palestine, and Israel. Syria plans to build dams and withdraw more water from the Jordan River, decreasing the downstream water supply for Jordan and Israel; where Israel threatens to destroy the dam.
Most of the water in the middle east comes from three shared river basins: the Nile, Jordan, and Tigris-Euphrates.
Most likely in the future, these water short countries are going to face conflicts over access to water resources.

4. Water Conflicts in the Middle East (continued)
Turkey is in control of the Tigris Euphrates river, controlling how much water flows down stream to Iraq and Syria before it empty’s into the Persian Gulf.
Turkey is building dams, and if these dams are complete, it will reduce the flow of water downstream to Syria ad Iraq by 35%.

5. Water’s Importance and Unique Properties
Keeps us alive
Moderates climate
Sculpts the land
Removes and dilutes wastes and pollutants
71% of the Earth’s surface is water

6. Importance of Water Properties
Running water can quickly erode topsoil rendering farmland infertile and streams contaminated.
Lack of access to clean water supplies can quickly lead to dehydration and death.
Chemical spills, excess nutrients & acids dissolved in H20 can lead to massive die offs.
Michael D. Lee Ph.D. Geography and Environmental Studies

7. Properties of Water
Water filters out wavelengths of the suns UV radiation that would harm some aquatic organisms
Water exists as a liquid because of the strong hydrogen bonds between water molecules
Water moves easily-from one physical state to another, and from one place to another.
Water slowly absorbs and releases large quantities of energy.
Water is a superior solvent.
Makes up all living things.
Attractive forces between the molecules of liquid water cause its surface to contract and to adhere to and coat a solid.
Water expands when it freezes.

8. The Story of Drinking Water Online Game
Water Supply & Use
The Story of Drinking Water Online Game
(Quiz yourself!)

9. Comparison of population sizes and shares of the world’s freshwater among the continents.

10. Supply, Renewal, and Use of Water Resources
Only a small amount of water is fresh water (0.01%) that is continuously recycled through the hydrologic cycle.
97.4% of the world water is salty ocean water .
Surface runoff is the water that evaporates/transpires back into the atmosphere and does not infiltrate the ground.
Watershed (Drainage Basin) - is the region at which surface water drains into another body of water (lakes, streams, wetlands, and reservoirs )
Reliable runoff- amount of water we can generally count on as a stable source of freshwater from year to year.

11. Surface Water

12. Hydrologic Cycle- Know how water moves through from land and atmosphere!
Powered by solar energy and gravity
Evaporation and precipitation
Continuous recycling of water
Runoff
Infiltration
Evaporation
Temporary storage as snow and ice
Temporary storage in lakes
Temporary storage in plants (transpiration) and animals
Chemical reactions with rocks and minerals
Volcanism also causes melting of snow caps and mudflows as melted water mixes with ash
Source of additional water? volcanism (steam)

13. What is Groundwater?
Ground water is one of the most important sources of water on earth it contains more water than any other source of fresh water. It’s the precipitation that infiltrates and percolates through the voids in soil and rock.
Zone of aeration- Close to the surface; pores of soil contain a mixture or air and water
Zone of saturation- lower layers of soil where spaces between particles are completely filled with water.
Water table- located at the top of the zone of saturation; top of zone levels rises in wet weather and falls in dry.
Porosity/Permeability

14. Groundwater
Groundwater Animation

15. Aquifers
Porous, water-saturated layers of sand, gravel or bedrock through which groundwater flows; like a flowing “river under the ground”
Area of land that supplies water to aquifer is called the recharge area
Natural recharge is when water percolates downward, but sometimes lateral recharge occurs
Confined aquifers- bounded above and below by less permeable bedrock; confined by pressure
Unconfined aquifers- contains the water table
Journey through the Edwards Aquifer video

16. Groundwater Movement
Groundwater moves from recharge area through an aquifer and out a discharge area
well, spring, lake, geyser, artesian well, steam, ocean
Normally moves downhill at only a meter per year!
Some aquifers get little recharge and were formed thousands of years ago
Removal from these nonrenewable resources is called water mining.

17. Cooling towers of power plants
Where is our water going?
Most of the fresh water being used up is to irrigate croplands (70% ) and industries use up 20%, and cities/residences use up only 10%.
• Some parts of the U.S such as the eastern states get plenty of irrigation, while western states are very dry, while other states have contaminated aquifers.
• This problem may cause “water wars” in the future because developing urban areas are in need of water. (ie. California/Arizona and Middle East)
Cooling towers of power plants

18. Too little Water There are four causes of water scarcity:
Drought – prolonged period of low precip., high evapor. rate
Dry climate
Desiccation- drying of exposed soil due to deforestation/overgrazing
water stress – increasing #’s of people relying on limited runoff
The volumes of some of the worlds lakes and rivers have shrunk drastically because mostly because of human withdrawals of water for irrigation and for industry.
About 1/6 of the percent of people on this earth do not have enough access to fresh water, and it is believed that will continue to increase.
Too little Water

20. Global Water Shortage
We can increase water supplies by building dams, bringing in water from elsewhere withdrawing groundwater, converting saltwater to freshwater and importing food.

21. Who owns water???
There is major controversy of whether water supplies should be owned and managed by governments or by private corporations.
Governments hiring private companies to manage water resources must set standards and maintain strict oversight of such contracts.
The movie F.L.O.W. – For the Love of Water

22. How can we increase our freshwater supplies?
Dams and reservoirs
Transporting surface water
Withdrawing groundwater
Desalination
Water conservation
Better use of natural hydrologic cycle

23. Using Dams and Reservoirs to Supply More Water
Advantages:
Disadvantages:
Cheap, constant electricity
Reduces downstream flooding
Storing water year-round for irrigation and cities.
Reservoirs can provide recreational activities
Displaces people
Disrupts aquatic ecosystems (i.e. fish migrations/ runoff)
Flooding can destroy surrounding forests and croplands
Large loss of water through evaporation
Reservoirs behind dams collect increased levels of silt and slow water flow.

24. Map of decommissioned dams (click yellow dot for Kissimmee River Dam – removal part of CERP)

26. Colorado River Basin Colorado River has so many dams
it doesn’t reach the ocean.
Used for hydroelectricity, irrigation (80%) and recreation (whitewater rafting, camping, fishing) for over 7 states.
Lake Mead at Hoover Dam, October, According to Scripps researchers, Lake Mead could be dry by 2021 if climate changes as expected and future water usage is not curtailed. Photo courtesy of Dr. Ken Dewey, Applied Climate Sciences Group, University of Nebraska, Lincoln

27. The Flow of the Colorado River Measured at Its Mouth Has Dropped Sharply

28. China’s Three Gorges Dam
Good News:
Provide electricity of 18 coal burning plants and reduce China’s dependence on coal
Larger ships can enter interior = less in transportation costs
Reduce greenhouse gas emissions
Improve air quality
China’s Three Gorges Dam
Once completed (2013), it will be the world’s largest dam and reservoir.
Bad News:
1.9 M people being relocated
Build over a seismic fault
Flooding potential
High costs

29. Transferring Water from One Place to Another
Moving water from water-rich areas to water-poor through tunnels, aqueducts, and underground pipe can be helpful and harmful.
Case Studies showcasing this include the Aral Sea, the California Water Project, and Canada’s James Bay Watershed.

30. Case Study: Siberia’s Aral Sea Disaster
Aral Sea was once the world’s 4th largest freshwater lake.
Since 1960, enormous amounts of irrigation water have been diverted from the inland Aral Sea and its two feeder rivers, resulting in a large-scale water transfer project for irrigation of cotton and rice cropland.
This large-scale water diversion project, coupled with droughts and high evaporation rates in this area’s hot and dry climate, has caused a ecological, economic and health disaster.

31. Aral Sea
Led to 85% loss of wetlands loss of major birds and mammals in the area
Salt concentrations increase decrease in fish pops. and spreading of salt to croplands and glaciers
Increase in salt, dust and toxic contaminants in Aral Sea watershed has led to health problems.
*In 1999, UN and World Bank stepped in and spent $600M to purify drinking water and upgrade irrigation and drainage systems.

32. Case Study: The California Water Transfer Project
This project uses a maze of giant dams, pumps, and aqueducts to transport water from water-rich northern California to southern California’s heavily populated arid and semi-arid agricultural regions.
It could degrade the Sacramento River, threaten fisheries, and reduce flushing action that helps clean San Francisco Bay of pollutants.

33. Case Study: Canada’s James Bay Watershed Transfer Project
Produce hydroelectric power for Canada and the United States.
50-year project including over 600 dams that will alter the flow of 19 rivers.
Would flood a boreal forest and tundra
Displace indigenous tribes
The second phase of the project was postponed indefinitely because the first phase produced more power than could be sold, as well as increase opposition to the project by environmentalist and indigenous tribes.

34. Withdrawing Groundwater
Most aquifers are renewable sources unless the water is removed faster than it is replenished or becomes contaminated.
Aquifers provide drinking water for about one-fourth of the world’s population.
In U.S., groundwater is being withdrawn at 4x’s its replacement rate.
Bad news: the water tables are falling in many areas of the world as the rate of pumping out water exceeds the rate of natural recharge from precipitation. (mostly for crop irrigation)

35. Aquifer Depletion from Groundwater Overdraft in the United States

36. Other Effects of Groundwater Overpumping
Groundwater overpumping can cause land to sink, and contaminate freshwater aquifers near coastal areas with saltwater. (Saltwater Intrusion)

37. Withdrawing Groundwater
TRADE-OFFS
Withdrawing Groundwater
Advantages
Disadvantages
Useful for drinking and irrigation
Aquifer depletion from overpumping
Sinking of land (subsidence) from overpumping
Available year-round
Aquifers polluted for decades or centuries
Exists almost everywhere
Saltwater intrusion into drinking water supplies near coastal areas
Renewable if not overpumped or contaminated
Figure 13.7
Advantages and disadvantages of withdrawing groundwater. Question: Which two advantages and which two disadvantages do you think are the most important? Why?
Reduced water flows into surface waters
No evaporation losses
Increased cost and contamination from deeper wells
Cheaper to extract than most surface waters
Fig. 13-7, p. 321

38. Case Study: The Shrinking Ogallala Aquifer
Pumping water from the world’s largest aquifer has greatly increased food production, but over pumping is a serious problem in some areas.
Transformed the most arid areas of the midwest, into the most productive agricultural regions in the United States.

39. Ogallala Aquifer

40. Can Deep Aquifers Supply More Water?
Scientists are evaluating huge, deep aquifers as a source of water.
Two major concerns about tapping water from these deep aquifers:
We know little about the geological and ecological impacts of pumping from deep aquifers.
No international water treaties govern the rights to and ownership of water underlies several countries.

41. SOLUTIONS Groundwater Depletion Prevention Control Waste less water
Raise price of water to discourage waste
Subsidize water conservation
Tax water pumped from wells near surface waters
Limit number of wells
Figure 13.11
Ways to prevent or slow groundwater depletion by using water more sustainably. Question: Which two of these solutions do you think are the most important? Why?
Set and enforce minimum stream flow levels
Do not grow water-intensive crops in dry areas
Divert surface water in wet years to recharge aquifers
Fig , p. 324

42. Converting Saltwater to Freshwater (15-6 continued)
Removing saltwater from seawater will probably not be done widely because of high costs and what to do with the resulting salt.
Ways to desalinate seawater include:
Distillation- heat saltwater until it evaporates, leaves behind salts, and collect freshwater in cooler condensation chamber.
Reverse osmosis- pumping saltwater at high pressure through a thin membrane that forces fresh water through, but traps salt solutes.
15,000 desalination plants in 125 countries

43. Reverse Osmosis

44. Major Problems with Desalination
High cost
Death of marine organisms
Large quantity of brine wastes
Future economics

45. Ashkelon Plant supplies 15%
of Israel’s Households
water needs-
Largest plant in 2005

46. Seeding Clouds and Towing Icebergs and Big Baggies (15-6 continued)
Seeding clouds with tiny particles of chemicals to increase rainfall, or towing icebergs or huge bags filled with freshwater to dry coastal areas, probably will not provide significant amounts of fresh water in the future.
Bad News:
Cloud seeding does not work very well in very dry areas where rain is needed most, because there are few clouds.
There is no compelling scientific evidence that it works.
Introduces large amounts of chemicals to soil and water
Legal disputes over ownership of cloud water.

49. Reducing Water Waste
We waste about two-thirds of the water we use but using water more efficiently could reduce wastage to about 15%.
Worldwide – 65-70% freshwater loss
Evaporation, leaks
Education of benefits of water conservation
According to water resource experts the main cause of water waste is that we charge too little for water- Regulating water prices, decrease government subsidies for supply water and increase subsidies for water waste reduction
Improve irrigation efficiency
Improve collection efficiency
Use less in homes and businesses

50. Major Irrigation Systems

51. Drip Irrigation: MOST EFFICIENT!
Gravity Flow: efficiency 60% and 80% with surge valves. Water usually comes from an aqueduct system or a nearby river.
Drip Irrigation: MOST EFFICIENT!
Center Pivot: efficiency 80% with low pressure sprinkler and 90-95% with LEPA sprinkler. Water usually pumped from underground and sprayed from sprinklers.

54. Too Much Water
Flooding is caused by increased precipitation and human impacts on earth.
Used to occur every 50 years but now come about every 4 years
Rapid population growth, deforestation, overgrazing , unsustainable farming on steep and easily erodible mountain slopes

55. Hillside Before and After Deforestation

56. Floodplain- when a stream overflows and spills over into surrounding land area

57. Benefits of Floodplains
Highly productive wetlands
Provide natural flood and erosion control
Maintain high water quality
Recharge groundwater
Fertile soils
Nearby rivers for transporation use and recreation
Flatlands for urbanization and farming

58. Dangers of Floodplains and Floods
Deadly and destructive
Human activities worsen floods
Failing dams and water diversion
Hurricane Katrina and the Gulf Coast
Removal of coastal wetlands

59. Before and During a Flood in St. Louis, Missouri

60. Case Study: Floodplains of Bangladesh
Dense population
Located on coastal floodplain
Moderate floods maintain fertile soil
Increase frequency of large floods
Development in the Himalayan foothills
Destruction of coastal wetlands
In struggle to survive, the poor in Bangladesh have cleared many of the coastal mangrove forests for fuel woods, farming, and aquaculture ponds for raising shrimp. This has led to more severe flooding.

63. How Can We Use Water More Sustainably?

64. Take the home water audit quiz online to see how much water YOU use!
Due Tues. 2/8