Water Issues in the US

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1 Water Issues in the US Emphasizing Two Western US Water Resources The Colorado River The High Plains Ogallala Aquifer Presented by Dorothy E. Boatman

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4 One estimate of global water distribution Water source Water volume, in cubic miles Water volume, in cubic kilometers Percent of freshwater Percent of total water Oceans, Seas, & Bays 321,000,000 1,338,000, Ice caps, Glaciers, & Permanent Snow 5,773,000 24,064, Ground water 5,614,000 23,400, Fresh 2,526,000 10,530, Saline 3,088,000 12,870, Soil Moisture 3,959 16, Ground Ice & Permafrost 71, , Lakes 42, , Fresh 21,830 91, Saline 20,490 85, Atmosphere 3,095 12, Swamp Water 2,752 11, Rivers 509 2, Biological Water 269 1,

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10 MILLIONS Regional US Population by Decade from Northeast Midwest South West DECADES

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15 Two Sides of the Scarcity Coin: Energy and Water

16 Energy Cost of Obtaining Clean Water Lake/River Groundwater Wastewater Seawater Energy needed to get 1 million gallons of clean water (kilowatth) Percent increase vs. lake/river

17 Transportation as problem: Major Oil Consumer Major Carbon Emitter Solutions to replace gasoline: Electricity for plug-in vehicles Biofuels But: replacements are much more water intensive than gasoline

18 Alternative Vehicles Gallons of Water Depleted to Travel 100 Miles Ethanol vehicle: Hydrogen fuel cell vehicle: 42 Plug-in-hybrid electric vehicle: 24 Gasoline vehicle: 7-14

19 Replacements: much more water intensive than gasoline Electric/hybrid car: generating electricity withdraws 10 X as much water and car uses 3 X as much per mile Biofuels: from production to tank filling, uses up to 20 X more water than gasoline

20 Biofuels are big water users: The entire production cycle from growth of irrigated crops to biofuel pumped into a car can consume 20+ X more water for every mile traveled than does the production of gasoline. Scaled up to the 2.7 trillion miles/year traveled by U.S. passenger vehicles, water could well become a limiting factor.

21 *Water Needed (Gallons X 1000) to Generate 1 Megawatt-Hour of Electricity Using: Gas/steam Combined Cycle: Coal & oil: Nuclear: *For plants that draw & dump water; plants with cooling towers use less

22 Conflicts between Energy Generation and Water Usage: Water for Fracking: conflicts between ranchers & farmers (e.g., S. Dakota) Water for Biofuel Generation: withdrawal from aquifers conflicts with cities (Champaign &Urbana, Ill) and farmers

23 Water Cost of Everyday Items Item Gallons of water required 1 tomato 1 KW-H electricity 1 loaf of bread 1 pound of beef 1 ton of steel 1 person/1 day survival US household/ day

24 Agriculture Biggest user of freshwater. In the United States, agriculture uses 49% of total freshwater. Irrigation uses 80% of this volume.

25 Fracking Compared to Agriculture Irrigation: uses 128 billion gallons/day returns to ground or stream; evaporation leads to more rain Fracking: uses billion gallons/year used water contaminated; disposed of, removed from system; small withdrawals have significant local impact

26 Who Has Rights to Use the Water? Each US State & Territory has its own water laws that establish water rights that may be land-based, use-based, or both.

27 Surface Water US has two systems for determining water rights Riparian Water Rights: (derived from English common law); common in the east Prior Appropriation Water Rights: (developed in Colorado and California); common in the west.

28 Riparian Water Rights Riparian land is a parcel that is adjacent to a watercourse. Riparian rights permit the riparian landowner to use the water from the watercourse. A principal reason for confining riparian rights to lands that border the stream is so after its use, the water returns to the stream.

29 Doctrine of Prior Appropriation: "first in time, first in right The first person to put the water to a beneficial (productive) use has the best legal right to continue to use the water." Those who put water to a beneficial use at a later time have a subordinate water right and generally will have to not use water if there is not enough water to meet everyone's needs. senior water rights junior water rights

30 Groundwater Law States apply one of four doctrines as the basis of ground water law: * absolute ownership * reasonable use * prior appropriation * correlative rights

31 Absolute Ownership landowner can withdraw any water beneath his land with no liability to neighbors (TX) Reasonable Use landowner must be reasonable in using his rights to water and use of his property, respecting rights of others with similar rights (AZ, NB,UT) Prior Appropriation First in time, first in right (12 western states) Correlative Rights reasonable use until drought, then water apportioned by of percent of land overlying the water source (CA)

32 Federal Water Law Commerce clause in the US Constitution "The Congress shall have power to... regulate commerce with foreign nations, and among the several states, and with the Indian tribes; Clean water Navigation - navigation servitude Commerce clause - prohibit state action Federal licenses; pre-emption over state State interaction with federal laws Federal projects - reclamation act, federal power act

33 Federal Reserved Water Rights Cases where federal, not state, law dictates who is entitled to use the water Indian reserved rights: allows federal government to allocate water resources to reservations and to exempt them from state laws (1908) Federal land reserved rights: applies to all federally reserved public lands, national forests, national recreation areas, and national wildlife refuges (1963)

34 If State Laws usually apply, why be concerned with Federal Water Law? Federal lands are nearly 50% of the land in eleven contiguous western states and about 66% of the land in Alaska

35 37 Federal Agencies Have Some Control over Western Water Supply *Environmental Protection Agency- water quality Federal Energy Policy Act (1992)- water conservation *Army Corps of Engineers- Flood protection *Department of Interior *Bureau of Reclamation- water supply *Bureau of Land Management- manage public lands and water resources Bureau of Indian Affairs US Fish & Wildlife Service US Geological Survey States have additional agencies, e.g., Natural Resource Agency

36 Interstate Compact: US Constitution s main mechanism for sharing water resources among states Cannot deal with situations where water is very scarce States lack means of enforcing compacts Monitoring water use is expensive & difficult for cash strapped states Most compacts assign a specific quantity of water rather than a percentage. In a drought, each state can claim to have been denied its fair share of water. Most Interstate water compacts lead to long-running legal & administrative battles.

37 Colorado River Basin

38 Colorado River Length: 1450 miles from head waters in the Rocky Mountains of Colorado to the Gulf of California Drainage basin covers portions of 7 US states: Upper basin: Colorado, New Mexico, Utah, Wyoming; Lower basin: Arizona, California, Nevada. Snow based hydrological system: 90% of flow is from snowmelt in 3 upper basin states, Colorado, Utah, Wyoming. Most of the demand and use are in Lower basin states, Arizona, California, Nevada.

39 Colorado River Mean flow is 15 million acre-feet (MAF)/year, Flow is lower than other major US River systems such as Columbia or Mississippi. It is the largest source of surface water in the arid South West

40 Colorado River Basin Water Serves: Power generation Lower water costs Drinking water supply for 36 million citizens Irrigation water for 15% of nations crops Recreation economy worth $26 billion employing 250 thousand Americans

41 Colorado River Compact Water use of the Colorado River is Governed by the Colorado River Compact of 1922, an interstate compact between 7 states: Upper Basin Colorado, New Mexico, Wyoming, Utah Lower Basin Arizona, California, Nevada

42 Upper Basin, 7.5 million acre ft/year (293 m³/s) total Colorado 51.75%* Utah 23.00%* Wyoming 14.00%* 3.86 million acre ft/year (150.7 m³/s) 1.71 million acre ft/year (67.0 m³/s) 1.04 million acre ft/year (40.8 m³/s) Colorado River Water Allocation New Mexico 11.25%* 0.84 million acre ft/year (32.8 m³/s) Arizona 0.70% 0.05 million acre ft/year (2.0 m³/s) *Percentages with a star are a percentage of the total after Arizona's 0.05 million are deducted. Arizona's percentage is of the total. Lower Basin, 7.5 million acre ft/year (293 m³/s) total California 58.70% Arizona 37.30% 4.40 million acre ft/year (172 m³/s) 2.80 million acre ft/year (109 m³/s) Nevada 4.00% 0.30 million acre ft/year (12 m³/s) Additionally, 1,500,000-acrefoot ( m3)/year of Colorado River water is allocated to Mexico by treaties.

43 Major Storage Dams: Lake Powell & Lake Mead: 90% of the surface water storage of Colorado Basin. Lake Powell: formed by Glen Canyon Dam; collects water from Utah, Wyoming, Colorado, New Mexico; disperses water to Lake Mead; Lake Mead: formed by Hoover Dam; collects water from Lake Powell; disburses water to Nevada, Arizona, California and Mexico;

44 Problems Due to Record Low Flow River Flow into Lake Powell in low flow years was 50% below average, leading to record low levels of Lakes Powell and Mead. By Compact, states of Lower Basin must get aggregate of 7 MAF over 10 y period. A sharp drop in Lake Powell storage a matter of legal, scientific, and public policy concern.

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46 Water Level in Lake Powell March 25, 1999

47 Water Level in Lake Powell April 26, 2013

48 Drawbacks to damming, storing, and transporting Colorado River Water Colorado most exploited river in US. Most of the water is for Las Vegas, Phoenix, and Tuscon, and irrigation. River water gets saline due to evaporation. US built a desalination plant at the Mexican border so water could be used for drinking & irrigation. Wetlands of the Col. River delta & its ecosystem very badly degraded Some years, no river flow reaches ocean.

49 Problems of Low Flow Bureau of Reclamation will cut flow of water into Lake Mead in 2014 to historic low. If dry weather continues, lower water levels in Lake Powell will cut off power production at Glen Canyon Dam by winter 2015 affecting power supply and pricing in 6 states. Less water into Lake Mead may bring the level below the water intake pipe to Las Vegas by spring 2015; cut-off drinking water. By winter 2015, low levels of water in Lake Mead could result in major decline in power production by Hoover Dam. This would affect supply & cost of power for Nev, Ariz, & Cal. Southern Cal uses below-market-rate power from Hoover Dam to pump water to its cities. If forced to buy market rate power elsewhere, water prices would rise.

50 Predictions for the Future By 2050, due to global warming, temperatures are predicted to increase in the Colorado River Basin by degrees. Total precipitation may not change, but snowmelt is expected to decline. Combined with related changes in evaporation and soil moisture, this will cause a decline and seasonal shift in runoff for most of Colorado s River basins. Average flow could decrease nearly 10% by midcentury. Therefore, there will be a reduction in total water availability by midcentury.

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52 Counter Measures to Overcome Water Shortage: Urban & agricultural water conservation and recycling of water Water banking Can lead to a secure water future for the Southwest.

53 The High Plains and Ogallala Aquifer

54 Flowing Groundwater Blue lines show the direction of groundwater movement United States Geological Survey

55 Schematic Cross Section of Aquifer Types This figure shows different types of aquifers and water wells, including unconfined aquifer, confined aquifer, water table well, artesian well, and flowing artesian well. Point of triangle is water level in each well and water table in other parts of figure. Water level in artesian well is at potentiometric surface and above local water table (dashed blue line) due to extra pressure on groundwater in confined aquifer. Water in flowing artesian well moves above land surface. Source: Colorado Geological Survey

56 Ogallala Aquifer The Ogallala Aquifer is a vast, shallow water table aquifer located beneath the Great Plains in the United States. It is one of the world's largest aquifers, and underlies an area of approximately 174,000 mi² (450,000 km²) in portions of eight states: (South Dakota, Nebraska, Wyoming, Colorado, Kansas, Oklahoma, New Mexico, and Texas). The aquifer is part of the High Plains Aquifer System.

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58 Ogallala Aquifer Water source dates from 3 million years ago from vanished rivers. It percolates in a saturated gravel bed that is more than 1000 ft thick in the North and only a few ft thick in the Southwest. Industrial-scale extraction began after WWII. Irrigation wells in West Texas jumped from 1166 in 1937 to more than in Some of the poorest farming regions in the country were transformed to one of its wealthiest.

59 Ogallala Aquifer Fast Facts If spread across the US, the aquifer would cover all 50 states with 1.5 ft of water If drained, it would take more than 6,000 years to refill naturally More than 90% of the water pumped is used to irrigate crops $20 billion a year in food & fiber depend on the aquifer Provides drinking water for 80% of people living above it (1990: 2,300,000 million)

60 More Ogallala Aquifer Facts The aquifer overlies about 27% of the irrigated land in the United States. It yields about 30% of the ground water used for irrigation in the United States. Since 1950, agricultural irrigation has reduced the saturated volume of the aquifer by an estimated 9%. Depletion is accelerating, with 3% lost between 2001 and 2008 alone. Certain aquifer zones are now empty; these areas will take over 100,000 years to replenish naturally through rainfall.

61 Depletion of the Ogallala Aquifer By 1980 water levels had dropped by an average of 10 ft throughout the region. In the central & southern parts of the High Plains some drops exceeded 100 ft. In some places farmers withdrew 4-6 ft/yr while nature put back 1 inch. In 1975, the net depletion equaled the flow of the Colorado River. Today, the Ogallala Aquifer is being depleted at an annual volume equivalent to 18 Colorado Rivers.

62 557 mi² area of fields (1443 km²) in Kansas which are watered from the Ogallala aquifer with center pivot irrigation systems

63 Strategies for when the Groundwater is Gone. Some growers are moving to dryland farming, growing wheat & other crops that do not need irrigation. Others are planting sunflowers which need 30% less water than corn. Others are returning to native grasslands that can be browsed by cattle or buffalo, or provide hunting and ecotourism, etc.

64 Remedies to Ease Water Shortages Conservation: Use less water and use it more effectively. Examples, water-efficient appliances, low-flow toilets & showers. Behavior modification: turn off water during tooth brushing, grow native plants for landscaping, fix leaky faucets, etc. Agricultural Water Conservation

65 Agricultural Water Conservation As much as ½ of all water diverted for agriculture yields NO food. This is a major area where conservation can pay off. Irrigation uses more water than the public water supply. Rainwater harvesting Grow crops in areas where natural rainfall can support them Use efficient irrigation systems such as drip systems (reduces evaporative losses) No-till farming: reduces evaporative losses by covering the soil Reuse treated wastewater for irrigation. Bank (surface) water underground during high flow/low use months (e.g. Winter). This reduces loss due to evaporation (3% in Lake Powell)

66 Ease Water Shortages by Changing Technologies, and making Substitutions Change in Diet: Grain to produce 1 lb beef= 2000 to 8500 gallon water 1 lb corn= 100 to 250 gallons water Change in Manufacturing: Before WWII: 1 ton steel= tons of water Now: 1 ton steel <= 6 tons of water Substitute Components: aluminum for steel, 1 ton Al= 1.5 tons of water Shift where water used: 250,000,000 gallons of water in agriculture= fewer than 10 jobs 250,000,000 gallons of water in high-tech jobs in Cal= 100,000 jobs

67 Suggested Solutions for Resource Management and Conflict Resolution The federal government should create a single overseer of water, and Congress should then develop a plan for integrated water and energy policy making. First, Congress should restore funding for the U.S. Water Resources Council and the regional River Basin Commissions. Fostering communication among Washington and the states, they can help prevent disputes from arising. Second, the president should appoint special mediators to resolve interstate water disputes, so that states have an alternative to resorting to the courts.

68 Some of the Information Sources for this Talk Scientific American Aquaformia Aquapedia High Country News Wikipedia North Dakota Southern University Dept. of Agribusiness & Applied Economics GE Radosevich, Western Water Law and Irrigation Return Flow National Atlas.Gov Water Science and Technology Board National Academy of Sciences US Geological Survey Websites