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Chapter 14Water ResourcesAll organisms are made up mostly of water

Plays a key role in; -sculpting the earths surface -moderating climate -diluting pollutionWhy is water so important?

Hydrogen BondingLiquid over a large temperature rangeChanges Temperature SlowlyMaintains pH

High Heat of EvaporationGreat Dissolving PowerAdhesion, Cohesion and CapillarityExpands when frozen

I. WATERS UNIQUE PROPERTIES

Also called the HYDROLOGICAL CYCLEProcess by which water alternates form due to evaporation and condensation.

A. Water into the atmosphere B. Water out of the atmosphere C. Water over and through the soilII. THE WATER CYCLEWater enter the atmosphere by two processes. 1. Evaporation 2. Transpiration

The amount of water that the atmosphere can hold depends on the temperature. High temperature = increased moisture Low temperature = decreased moistureA. Water Into The AtmosphereRELATIVE HUMIDITY: the amount of water vapor in the air compared to the maximum that it can hold at a particular temperature.

Increased humidity = decreases evaporationDecreased humidity = increased evaporationFactors that influence EvaporationPrecipitation:All forms of moisture out of the atmosphereRain falls unevenly across the earths surface. Some areas receive practically no precipitation and other areas receive heavy rain on a daily basis.Three principal factors control global water deficits and surpluses:Global atmospheric circulationProximity to water sourcesTopographyB. Water Out Of The Atmosphere

Rain Shadow

9Rain Shadow Effect:

Air sweeps up the windward side of a mountain, pressure decreases, and the air cools.

Moisture in the air condenses.Rain falls on the mountaintopsCool, dry air descends creating dry areas with very little precipitation.The Rain Shadows Effect on Precipitation101. Runoff or Surface Water:

-Water that flows directly over the surface into streams that form rivers which make lakes and eventually run into the oceans. Watershed or Drainage Basin: -The land area that drains a particular waterway

Example: Ohio River Watershed is where we liveC. Water Over And Through The Soil

Infiltration:

Water that doesnt runoff, is absorbed by the soil or evaporates.

Infiltration is the process of water seeping through the various layers of soil.

AquifersPorous layers of sand, gravel, or rock lying below the water tableArtesian Aquifer Pressurized aquifer where water flows without pumping. (Examples: seeps and springs)Recharge zones:Areas where water infiltrates into an aquiferRecharge rate is often very slow.Where is Groundwater Stored?14Groundwater in Aquifers

15Ground Water

Evaporation and transpirationEvaporationStreamInfiltrationWater tableInfiltrationUnconfined aquiferConfined aquiferLakeWell requiring a pumpFlowingartesian wellRunoffPrecipitationConfinedRecharge AreaAquiferLess permeable materialsuch as clayConfirming permeable rock layer-97% of water is found in the oceans-3% freshwater - most locked up in glaciers or too deep to obtain.

-0.014% is available for useIII. SUPPLY OF WATER RESOURCES

FRESHWATER RESOURCES

FreshwaterReadily accessible freshwaterBiota0.0001%Rivers0.0001%Atmosphericwater vapor0.0001%Lakes0.0007%Soilmoisture0.0005%Groundwater0.592%Ice capsand glaciers0.592%0.014%Fig. 13.2, p. 296Water may reside briefly in one compartment or stay there for eons.

The length of time water typically spends in a compartment is called the Residence Time.

Average residence time of water in the ocean:

3,000 years before entering the water cycle.

Major Water Compartments2197% of all liquid water on the earth.

90% of the earths biomass

Ocean currents moderate the climate by redistributing warm and cold water around the earth like a global ocean conveyor belt.The Oceans as a Major Water CompartmentGlobal Ocean Conveyor System

Glaciers, Ice, and Snow2.4% of worlds water is classified as fresh.90% in glaciers, ice caps, and snowfieldsNow, Antarctic glaciers contain nearly 85% of all ice in the world.Greenland, together with ice floating around the North Pole, is another 10%.Frozen Water Compartments24Ground water is the second largest reservoir of fresh waterGround Water Compartments25Rivers and StreamsPrecipitation that does not evaporate or infiltrate

Discharge:The amount of water that passes a fixed point in a given amount of timeUsually expressed as cubic feet per secondRiver & Streams Water Compartments26Major Rivers of the World

Lakes and PondsPonds: Bodies of water shallow enough for rooted plants to grow over most of the bottom.Lakes:Inland depressions that hold standing fresh water year-round.Lakes and Ponds Water Compartments28WetlandsPlay a vital role in hydrologic cycleLush plant growth stabilizes soil and retards surface runoff, allowing more aquifer infiltration.Disturbance reduces natural water-absorbing capacity, resulting in floods and erosion in wet periods, and less water flow the rest of the year.Half of U.S. wetlands are gone.Wetlands are Water Compartments29The Atmosphere:Among the smallest water reservoirs< 0.001% of total water supplyHas the most rapid turnover rateMechanism for distributing fresh water over landmasses and replenishing terrestrial reservoirsThe Atmosphere: A Small Water Compartment30

IV. Use of Water Resources in the United StatesEASTERN USA: The largest uses of water are for energy production, cooling, and manufacturing.

WESTERN USA:the major use is for agricultureMost serious problems: flooding, urban shortages, pollution.

United StatesIndustry 11%Public 10%Powercooling38%Agriculture38%Water Withdrawal and Consumption

Typical Household Water Use in U.S.

35Average Annual Precipitation

36

Acute shortageAdequate supplyShortageMetropolitan regions with population greater than 1 million

Personal Water UsageV. Too Little Water1. Dry climate3. Drought 2. Desiccation4. Water stressAccording to the experts there are four causes of water scarcity

HighNoneNorthAmericaSouthAmericaStressAfricaEuropeAsiaAustraliaWORLD WATER STRESSThere are six ways to increase the supply of freshwater in a particular area: A. Dams/Reservoirs B. Transferring Surface Water C. Withdrawing Groundwater D. Desalination E. Cloud Seeding F. Decreasing Water Waste

VI. INCREASING FRESHWATER SUPPLIESDams/Reservoirs -Capture and store runoff that can be released as needed. -Worldwide they have increased available runoff by 1/3. Pros-Increase water for irrigation and recreation-Hydroelectric powerCons-Decrease water flow-Destroy ecosystems-increase evaporation

Using Dams and Reservoirs to Supply More Water

Large lossesof water throughevaporationFlooded land destroys forests or cropland anddisplaces peopleDownstream flooding is reducedDownstream cropland andestuaries are deprived ofnutrient-rich siltReservoir is useful for recreation and fishingCan produce cheap electricity(hydropower)Migration and spawning of some fish are disruptedProvides waterfor year-roundirrigation ofcroplandChinas 3 Gorges Dam

Transferring Surface Water - Often associated with dams and reservoirs -Moving water from rich to depleted areas - California Water Project -Aral Sea

North BayAqueduct

South BayAqueductCalifornia AqueductCALIFORNIANEVADAUTAHMEXICOCentral ArizonaProjectColorado RiverAqueductLos AngelesAqueductShasta LakeOroville Dam andReservoirFeatherRiverLake TahoeSacramentoFresnoHoover Damand Reservoir(Lake Mead)Salton SeaPhoenixTucsonARIZONAColoradoRiverSacramentoRiverSan FranciscoSan Luis Damand ReservoirSanta BarbaraLos AngelesSan Diegohttp://ag.arizona.edu/AZWATER/arroyo/101comm.html

C. Withdrawing Groundwater -Removal of water from AQUIFERS -In U.S.; 50% of drinking water and 43% of irrigation water come from the ground.Pros-Available all year-Less evaporationCons-Decrease water table-Deplete aquifers-Draw chemicals/salt water-Aquifer subsidence-Cone of Depression

Major irrigationwellWell contaminatedwith saltwaterSaltwaterIntrusionNormalInterfaceFreshgroundwateraquiferInterfaceInterfaceSaltwaterSea LevelWater table

The Ogallala Aquifer

57D. Desalination:-Removal of salts from ocean or brackish water-Two methods:

Reverse OsmosisDistillation

Reverse OsmosisE. Cloud Seeding -Creating rain by dumping chemicals into the atmosphere

Drawbacks: -Cant be used in extremely arid regions-Introduce large amounts of chemicals into the soil/waterF. Decreasing Water Waste1. Commercially:A. Improving manufacturing processesB. Improving irrigation techniques

Gravity Flow(efficiency 60% and 80% with surge valves)

Water usually comes from an aqueduct system or a nearby river.Drip Irrigation(efficiency 9095%)

Above- or below-ground pipes or tubes deliver water to individual plant roots.Center Pivot(efficiency 80% with low-pressure sprinkler and 9095% with LEPA sprinkler)

Water usually pumped from underground and sprayed from mobile boom with sprinklers.

2. Home, Businesses

A. Reduce losses due to leakageB. Reform water lawsC. Water efficient landscaping (XERISCAPING)D. Water efficient appliances

VII. Too Much Water - Floods-Natural phenomena with spillage into FLOOD PLANS

-Renew and replenish-Aggravated by human activitiesOver $1 trillion in real estate in USA flood plains-Fertile soil-Ample Water-Transportation-Flat

Why Do We Build in the Flood Plains?

FloodplainLeveeFloodwallDamReservoir

1. CHANNELIZATION: Deepen, widen, and straighten waterwaysA. FLOOD CONTROL PRACTICES

2. ARTIFICIAL LEEVES: Walls to prevent water into floodplains

3. FLOOD CONTROL DAMS

Levee Failures During KatrinaBest practice for managing floodsDetermine flood frequency based on years of dataProhibit certain activities and buildingsConstruct a floodwayB. FLOOD PLAIN MANAGEMENT

Extremely severeVery severeModerately severeSomewhat severeNot severeFLOOD PRONE AREASA. SURFACE WATEREAST:Doctrine of Riparian Rights-Anyone whose land adjoins a stream has the right to use H2O as long as some remainsWEST:Principle of Prior Appropriation-1st come, 1st served -Later users are cutoff to satisfy early usersVIII. Water Rights in the USAGround water belongs to whoever owns the land above

Owners can withdraw as much as they want

Can sell, trade or lease to make moneyB. GROUND WATER COMMON LAW