WATER RESOURCESWATER RESOURCES

CHAPTER 14CHAPTER 14

WHY IS WATER IMPORTANT?WHY IS WATER IMPORTANT?

COVERS 71% OF EARTHCOVERS 71% OF EARTH– MOSTLY SALT WATERMOSTLY SALT WATER

NO PLANT OR ANIMAL CAN SURVIVE NO PLANT OR ANIMAL CAN SURVIVE WITHOUT ITWITHOUT IT

THERE IS NO SUBSTITUTE FOR ITS THERE IS NO SUBSTITUTE FOR ITS USESUSES– Sculptures earth’s surfaceSculptures earth’s surface– Moderates climateModerates climate– Dilutes pollutantsDilutes pollutants

PROPERTIES OF WATERPROPERTIES OF WATER HAS HYDROGEN HAS HYDROGEN

BONDS BETWEEN BONDS BETWEEN MOLECULESMOLECULES

HAS A HIGH BOILING HAS A HIGH BOILING AND A LOW FREEZING AND A LOW FREEZING POINTPOINT

HAS A HIGH HEAT HAS A HIGH HEAT CAPACITY SO:CAPACITY SO:– MODERATES CLIMATEMODERATES CLIMATE– PROTECT ORGANISMS PROTECT ORGANISMS

FOR TEMP. CHANGESFOR TEMP. CHANGES– GOOD COOLANTGOOD COOLANT

HAS A HIGH HEAT OF HAS A HIGH HEAT OF VAPORIZATIONVAPORIZATION– ABSORBS MUCH HEAT ABSORBS MUCH HEAT

AS IT CHANGES TO AS IT CHANGES TO WATER VAPORWATER VAPOR

IS A UNIVERSAL IS A UNIVERSAL SOLVENTSOLVENT

IONIZES INTO IONIZES INTO HYDROGEN AND HYDROGEN AND HYDROXIDE IONSHYDROXIDE IONS

FILTERS OUT UV LIGHTFILTERS OUT UV LIGHT

MORE PROPERTIESMORE PROPERTIES

HAS SURFACE HAS SURFACE TENSION, TENSION, COHESION, AND COHESION, AND ADHESIONADHESION

EXPANDS WHEN IT EXPANDS WHEN IT FREEZESFREEZES

HOW MUCH IS AVAILABLE?HOW MUCH IS AVAILABLE?

97.4% IS SALT WATER97.4% IS SALT WATER 2.6 % IS FRESH WATER - LOCKED IN 2.6 % IS FRESH WATER - LOCKED IN

ICE CAPS, GLACIERS OR POLLUTED, ICE CAPS, GLACIERS OR POLLUTED, SALTY OR DEEP GROUNDWATERSALTY OR DEEP GROUNDWATER

.014%IS AVAILABLE AS SOIL .014%IS AVAILABLE AS SOIL MOISTURE, USABLE MOISTURE, USABLE GROUNDWATER,WATER VAPOR AND GROUNDWATER,WATER VAPOR AND SURFACE WATERSURFACE WATER

PLANETS WATER BUDGETPLANETS WATER BUDGET

WATER IS CONSTANTLY BEING RECYCLED WATER IS CONSTANTLY BEING RECYCLED BY THE HYDROLOGIC CYCLEBY THE HYDROLOGIC CYCLE

UNEVENLY DIVIDED IN THE WORLD:UNEVENLY DIVIDED IN THE WORLD:– CANADA HAS .5% OF WORLD’S POPULATION CANADA HAS .5% OF WORLD’S POPULATION

AND 20% OF ITS WATERAND 20% OF ITS WATER– CHINA HAS 21% OF POPULATION AND 7% OF CHINA HAS 21% OF POPULATION AND 7% OF

ITS WATERITS WATER WATER SHORTAGES WILL INTENSIFY IN WATER SHORTAGES WILL INTENSIFY IN

THE FUTURE.THE FUTURE.

SUFACE WATERSUFACE WATER ANY PRECIPITATION THAT DOES NOT ANY PRECIPITATION THAT DOES NOT

INFILTRATE INTO THE GROUNDINFILTRATE INTO THE GROUND ABOUT 2/3 IS LOST BY SEASONAL FLOODS ABOUT 2/3 IS LOST BY SEASONAL FLOODS

AND IS NOT AVAILABLE TO HUMANSAND IS NOT AVAILABLE TO HUMANS OTHER 1/3 IS OTHER 1/3 IS RELIABLE RUNOFF RELIABLE RUNOFF AND WE AND WE

CAN COUNT ON AS A STABLE SOURCE OF CAN COUNT ON AS A STABLE SOURCE OF WATERWATER

WATERSHED OR DRAINAGE BASIN – WATERSHED OR DRAINAGE BASIN – REGION WHERE WATER DRAINS INTO A REGION WHERE WATER DRAINS INTO A STREAM, LAKE, RESERVOIR, WETLAND, OR STREAM, LAKE, RESERVOIR, WETLAND, OR OTHER BODY OF WATER.OTHER BODY OF WATER.

WHAT IS GROUNDWATER ?WHAT IS GROUNDWATER ?

WATER THAT INFILTRATES INTO THE WATER THAT INFILTRATES INTO THE GROUND, PERCOLATES DOWNWARD AND GROUND, PERCOLATES DOWNWARD AND FILLS UP PORES IN SOIL AND ROCKFILLS UP PORES IN SOIL AND ROCK

AREA ABOVE THE IMPERMEABLE ROCK AREA ABOVE THE IMPERMEABLE ROCK BARRIER THAT IS FILLED WITH WATER IS BARRIER THAT IS FILLED WITH WATER IS THE THE ZONE OF SATURATIONZONE OF SATURATION

WATER TABLE - TOP OF ZONE OF WATER TABLE - TOP OF ZONE OF SATURATIONSATURATION

ABOVE THIS IS ZONE OF AERATION - AIR ABOVE THIS IS ZONE OF AERATION - AIR AND WATERAND WATER

AQUIFERAQUIFER POROUS WATER-SATURATED LAYERS OF SAND, POROUS WATER-SATURATED LAYERS OF SAND,

GRAVEL OR BEDROCK THROUGH WHICH GRAVEL OR BEDROCK THROUGH WHICH GROUNDWATER FLOWSGROUNDWATER FLOWS

RECHARGE AREA - RECHARGE AREA - ANY AREA OF LAND THROUGH ANY AREA OF LAND THROUGH WHICH WATER PASSES DOWNWARD INTO AN WHICH WATER PASSES DOWNWARD INTO AN AQUIFERAQUIFER

THEY ARE NOT UNDERGROUND POOLS OF THEY ARE NOT UNDERGROUND POOLS OF FLOWING WATER THEY’S JUST SPONGES FLOWING WATER THEY’S JUST SPONGES

DISCHARGE AREA -DISCHARGE AREA - WELLS, LAKES, GEYSERS, WELLS, LAKES, GEYSERS, STREAMS, OR OCEAN STREAMS, OR OCEAN

GROUNDWATER MOVES FROM HIGH ELEVATION GROUNDWATER MOVES FROM HIGH ELEVATION TO LOWER ELEVATION AND HIGHER PRESSURE TO LOWER ELEVATION AND HIGHER PRESSURE TO LOWER PRESSURETO LOWER PRESSURE

GROUNDWATER MOVES VERY GROUNDWATER MOVES VERY SLOWLY - ONLY ABOUT A METER A SLOWLY - ONLY ABOUT A METER A YEARYEAR

MOVES FROM POINTS OF HIGH MOVES FROM POINTS OF HIGH ELEVATION AND PRESSURE TO ELEVATION AND PRESSURE TO POINTS OF LOW ELEVATION AND POINTS OF LOW ELEVATION AND PRESSUREPRESSURE

ROUTES & DESTINATION OF ROUTES & DESTINATION OF PRECIPITATIONPRECIPITATION

Fig. 13.3, p. 297

Evaporation and transpiration

Evaporation

Stream

Infiltration

Water tableInfiltration

Unconfined aquifer

Confined aquifer

Lake

Well requiring a pump

Flowingartesian well

Runoff

Precipitation

ConfinedRecharge Area

Aquifer

Less permeable materialsuch as clay

Confining permeable rock layer

Unconfined Aquifer Recharge Area

HOW IS WATER USED HOW IS WATER USED WORLDWIDE?WORLDWIDE?

MOST FOR MOST FOR IRRIGATION - 70%IRRIGATION - 70%

INDUSTRY - 20%INDUSTRY - 20% CITIES AND CITIES AND

RESIDENCES - 10%RESIDENCES - 10%

Slide 4

Fig. 13.4, p. 298

5,500

5,000

4,500

4,000

3,500

3,000

2,500

2,000

1,500

1,000

500

1900 1920 1940 1960 1980 2000

Wat

er u

se (

cub

ic k

ilom

eter

s p

er y

ear) Total use

Agricultural use

Industrial use

Domestic use

Year

IN THE UNITED STATES?IN THE UNITED STATES?

WE HAVE PLENTY OF FRESH WATER IN THE WE HAVE PLENTY OF FRESH WATER IN THE WRONG PLACESWRONG PLACES– EASTERN STATES HAVE AMPLE PRECIPITATIONEASTERN STATES HAVE AMPLE PRECIPITATION– WESTERN STATES HAVE TOO LITTLE WATERWESTERN STATES HAVE TOO LITTLE WATER– EAST - MAINLY USED FOR ENERGY EAST - MAINLY USED FOR ENERGY

PRODUCTION, COOLING AND MANUFACTURINGPRODUCTION, COOLING AND MANUFACTURING– WEST - MAINLY IN IRRIGATIONWEST - MAINLY IN IRRIGATION

1 automobile

1 kilogramcotton

1 kilogramaluminum

1 kilogramgrain-fed beef

1 kilogramrice

1 kilogramcorn

1 kilogrampaper

1 kilogramsteel

400,000 liters(106,000 gallons)

10,500 liters(2,400 gallons)

9,000 liters(2,800 gallons)

7,000 liters(1,900 gallons)

5,000 liters(1,300 gallons)

1,500 liters(400 gallons)

880 liters(230 gallons)

220 liters(60 gallons)

OUR MOST SERIOUS WATER OUR MOST SERIOUS WATER PROBLEMSPROBLEMS

EAST EAST – FLOODINGFLOODING– OCCASIONAL OCCASIONAL

URBAN SHORTAGESURBAN SHORTAGES– POLLUTIONPOLLUTION

WESTWEST SHORTAGE OF SHORTAGE OF

RUNOFF CAUSED RUNOFF CAUSED BYBY– LOW LOW

PRECIPITATIONPRECIPITATION– HIGH EVAPORATIONHIGH EVAPORATION– DROUGHTDROUGHT

Slide 7

Fig. 13.7a, p. 299

0-25

25-50

50-75

0-25

25-50

50-75

Average annual precipitation (centimeters)

Slide 8

Fig. 13.8b, p. 299

Acute shortage

Adequate supply

Shortage

Metropolitan regions with populationgreater than 1 million

Catawba River Basin

What causes water shortages?What causes water shortages?

DRY CLIMATEDRY CLIMATE DROUGHT - A PERIOD OF 21 DAYS OR DROUGHT - A PERIOD OF 21 DAYS OR

LONGER IN WHICH PRECIPITATION IS AT LONGER IN WHICH PRECIPITATION IS AT LEAST 70% BELOW AND EVAPORATION LEAST 70% BELOW AND EVAPORATION HIGHER THAN NORMAL.HIGHER THAN NORMAL.

DESSICATION - DRYING OF SOILDESSICATION - DRYING OF SOIL– DEFORESTATION, OVERGRAZINGDEFORESTATION, OVERGRAZING

WATER STRESS - TOO MANY PEOPLE AND WATER STRESS - TOO MANY PEOPLE AND NOT ENOUGH WATER.NOT ENOUGH WATER.

HOW CAN WE INCREASE HOW CAN WE INCREASE FRESHWATER SUPPLIES?FRESHWATER SUPPLIES?

BUILD DAMS AND RESERVOIRS TO STORE BUILD DAMS AND RESERVOIRS TO STORE RUNOFFRUNOFF

BRING SURFACE WATER FROM OTHER BRING SURFACE WATER FROM OTHER AREASAREAS

WITHDRAW GROUNDWATERWITHDRAW GROUNDWATER CONVERT SALT WATER TO FRESH WATERCONVERT SALT WATER TO FRESH WATER IMPROVE THE EFFICIENCY OF WATER USE.IMPROVE THE EFFICIENCY OF WATER USE.

Benefits & Drawbacks of DamsBenefits & Drawbacks of Dams

Benefits:Benefits:1.1. Control floodsControl floods2.2. Produce Produce

hydroelectric hydroelectric powerpower

3.3. Supply water for Supply water for irrigationirrigation

4.4. Recreation - Recreation - swimming, swimming, fishing, boatingfishing, boating

Drawbacks:Drawbacks:1.1. Reduce water flow Reduce water flow

below dambelow dam2.2. Silting at the damSilting at the dam3.3. Increase risk of Increase risk of

flooding if dam flooding if dam breaksbreaks

4.4. Destroys natural Destroys natural ecosystemecosystem

5.5. Increase water Increase water pollutionpollution

6.6. Promote saltwater Promote saltwater intrusionintrusion

Transferring WaterTransferring Water

Tunnels, aqueducts, Tunnels, aqueducts, and pipesand pipes

California Water California Water Project moves from Project moves from northern to northern to southern California.southern California.

Canada’s James Bay Canada’s James Bay project - another project - another major projectmajor project

Trying to harness the Trying to harness the wild rivers to wild rivers to produce electric produce electric powerpower

Slide 14

Fig. 13.13, p. 306

North BayAqueduct

South BayAqueduct

California Aqueduct

CALIFORNIA

NEVADA UTAH

MEXICO

Central ArizonaProject

Colorado RiverAqueduct

Los AngelesAqueduct

Shasta Lake

Oroville Dam andReservoir

FeatherRiver

Lake Tahoe

Sacramento

Fresno

Hoover Damand Reservoir(Lake Mead)

Salton SeaPhoenix

Tucson

ARIZONA

ColoradoRiver

SacramentoRiver

San Francisco

San Luis Damand Reservoir

Santa Barbara

Los Angeles

San Diego

Tapping into groundwaterTapping into groundwater

Pros:Pros:

1.1. Can be removed Can be removed year roundyear round

2.2. Is not lost by Is not lost by evaporationevaporation

3.3. Less expensive to Less expensive to develop than develop than surface water surface water systemssystems

Cons:Cons:

1.1. Lowers water tableLowers water table

2.2. Land subsidenceLand subsidence

3.3. Salt water intrusionSalt water intrusion

4.4. Moves contaminated Moves contaminated chemicals toward chemicals toward wellswells

5.5. Reduces stream flowReduces stream flow

Slide 20

Fig. 13.18, p. 309

WYOMING SOUTH DAKOTA

NEBRASKA

COLORADO

KANSAS

OKLAHOMA

NEW MEXICO

TEXAS

0 100Miles

Kilometers

Less than 61 meters (200 ft)

61-183 meters (200-600 ft)

More than 183 meters (600 ft)(as much as 370 meters or 1,200 ft.in places)

0 160

Slide 19

Fig. 13.17, p. 308

Major irrigationwell

Well contaminatedwith saltwater

SaltwaterIntrusion

NormalInterface

Freshgroundwater

aquifer

Interface Interface

Saltwater

Sea LevelWatertable

DesalinizationDesalinization

Removing Removing dissolved salts dissolved salts from ocean water from ocean water or brackish or brackish groundwatergroundwater

Two ways:Two ways:– DISTILLATIONDISTILLATION– REVERSE OSMOSISREVERSE OSMOSIS

Main plants are is Main plants are is Middle East and Middle East and parts of North parts of North AfricaAfrica

Two Two disadvantages:disadvantages:

1.1. Expensive - uses Expensive - uses energyenergy

2.2. Produces much Produces much wastewater (brine)wastewater (brine)

Cloud seeding & towing Cloud seeding & towing icebergsicebergs

Add silver iodide to Add silver iodide to clouds - produces clouds - produces condensation nuclei condensation nuclei

1.1. Need moisture to Need moisture to bring rainbring rain

2.2. Puts chemicals in soil Puts chemicals in soil and waterand water

3.3. Legal disputes over Legal disputes over ownership of water in ownership of water in cloudsclouds

Towing icebergs Towing icebergs to arid countries to arid countries such as Saudi such as Saudi Arabia & pump Arabia & pump water ashorewater ashore

1.1. Technology not Technology not availableavailable

2.2. expensiveexpensive

USING WATER MORE USING WATER MORE EFFICIENTLYEFFICIENTLY

WHY DO WE WASTE WATER?WHY DO WE WASTE WATER?

IT IS ESTIMATED THAT 60-70 % OF IT IS ESTIMATED THAT 60-70 % OF THE WATER PEOPLE USE THE WATER PEOPLE USE THROUGHOUT THE WORLD IS THROUGHOUT THE WORLD IS WASTED THROUGH EVAPORATION, WASTED THROUGH EVAPORATION, LEAKS, ETC.LEAKS, ETC.

Why do we waste so much water?Why do we waste so much water?

Government subsidizes “true cost” of Government subsidizes “true cost” of water creating artificially low water water creating artificially low water prices.prices.

Water laws that determine the legal Water laws that determine the legal rights of water users such as in the rights of water users such as in the U.S. (see p. 329 in text)U.S. (see p. 329 in text)

Fragmented watershed management Fragmented watershed management where water supplies are divided where water supplies are divided among local governments.among local governments.

WASTING LESS WATER IN WASTING LESS WATER IN IRRIGATIONIRRIGATION

ONLY ABOUT 40% OF WATER USED ONLY ABOUT 40% OF WATER USED REACHES CROPSREACHES CROPS

COULD:COULD:1.1. USE CENTER PIVOT LOW PRESSURE USE CENTER PIVOT LOW PRESSURE

SPRINKLERSSPRINKLERS2.2. USE LOW-ENERGY PRECISION USE LOW-ENERGY PRECISION

APPLICATION (LEPA) SPRINKLERSAPPLICATION (LEPA) SPRINKLERS3.3. USE TIME CONTROLLED VALVESUSE TIME CONTROLLED VALVES4.4. USE SOIL MOISTURE DETECTORSUSE SOIL MOISTURE DETECTORS5.5. USE DRIP IRRIGATION SYSTEMSUSE DRIP IRRIGATION SYSTEMS

TYPES OF IRRIGATIONTYPES OF IRRIGATION

Slide 21

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

Water usually comes from an aqueduct system or a nearby river.

Drip Irrigation(efficiency 90Š95%)

Above- or below-ground pipes or tubes deliver water to

individual plant roots.

Center Pivot(efficiency 80% with low-pressure

sprinkler and 90 Š95% with LEPA sprinkler)

Water usually pumped from underground and sprayed from

mobile boom with sprinklers.

Fig. 13.19, p. 311

IN HOMES AND BUSINESS:IN HOMES AND BUSINESS:

REDESIGN MFG. REDESIGN MFG. PROCESSES TO USE PROCESSES TO USE LESS WATERLESS WATER

XERISCAPING LAWNSXERISCAPING LAWNS DRIP IRRIGATION TO DRIP IRRIGATION TO

WATER LAWNSWATER LAWNS FIX LEAKSFIX LEAKS USE WATER METERS USE WATER METERS

TO MONITOR WATER TO MONITOR WATER USEUSE

LAWS REQUIRING LAWS REQUIRING WATER WATER CONSERVATIONCONSERVATION

USE WATER-SAVING USE WATER-SAVING TOILETS AND TOILETS AND SHOWERHEADSSHOWERHEADS

USE FRONT LOADING USE FRONT LOADING WASHING MACHINESWASHING MACHINES

USE GRAY WATERUSE GRAY WATER COLLECT RAINWATER COLLECT RAINWATER

TO USE IN TOILETS, TO USE IN TOILETS, REDUCE PERSONAL REDUCE PERSONAL

USEUSE

RAISING THE PRICE OF WATER IN RAISING THE PRICE OF WATER IN HOMES AND BUSINESSES IS ONE HOMES AND BUSINESSES IS ONE WAY TO REDUCE WASTEFUL WATER WAY TO REDUCE WASTEFUL WATER USE.USE.

CAUSES OF FLOODSCAUSES OF FLOODS

MAINLY CAUSED BY MELTING SNOW MAINLY CAUSED BY MELTING SNOW OR HEAVY RAINFALLOR HEAVY RAINFALL

STREAMS OVERFLOW INTO NATURAL STREAMS OVERFLOW INTO NATURAL FLOODPLAINS WHICHFLOODPLAINS WHICH– PROVIDE NATURAL FLOOD AND PROVIDE NATURAL FLOOD AND

EROSION CONTROLEROSION CONTROL– MAINTAIN HIGH WATER QUALITYMAINTAIN HIGH WATER QUALITY– RECHARGE GROUNDWATERRECHARGE GROUNDWATER

ADVATAGES OF ADVATAGES OF FLOODPLAINSFLOODPLAINS

FERTILE SOILFERTILE SOIL AMPLE WATER FOR IRRIGATIONAMPLE WATER FOR IRRIGATION FLAT LAND FOR FARMINGFLAT LAND FOR FARMING NEARBY RIVER FOR NEARBY RIVER FOR

TRANSPORTATION AND RECREATIONTRANSPORTATION AND RECREATION

HOW TO REDUCE SEVERITY HOW TO REDUCE SEVERITY OF FLOODING:OF FLOODING:

LEAVE VEGETATION ON HILLSIDESLEAVE VEGETATION ON HILLSIDES DON’T BUILD ON FLOODPLAINSDON’T BUILD ON FLOODPLAINS DON’T DRAIN WETLANDSDON’T DRAIN WETLANDS

CHANNELIZATIONCHANNELIZATION

WIDEN, DEEPEN OR STRAIGHTEN WIDEN, DEEPEN OR STRAIGHTEN STREAMS TO ALLOW MORE RAPID STREAMS TO ALLOW MORE RAPID RUNOFFRUNOFF

REDUCES FLOODING UPSTREAM BUT REDUCES FLOODING UPSTREAM BUT INCREASES UPSTREAM BANK INCREASES UPSTREAM BANK EROSION AND DOWNSTREAM EROSION AND DOWNSTREAM FLOODINGFLOODING

RUINS HABITATSRUINS HABITATS

ARTIFICIAL LEVEESARTIFICIAL LEVEES

REDUCE CHANCES OF WATER REDUCE CHANCES OF WATER OVERFLOWING INTO FLOODPLAINSOVERFLOWING INTO FLOODPLAINS

CONTAIN AND SPEED-UP STREAM CONTAIN AND SPEED-UP STREAM FLOWFLOW

FLOOD CONTROL DAMSFLOOD CONTROL DAMS

STORES WATER IN RESERVOIRS AND STORES WATER IN RESERVOIRS AND RELEASES IT GRADUALLYRELEASES IT GRADUALLY

FLOODPLAIN MANAGEMENTFLOODPLAIN MANAGEMENT

THE BEST APPROACHTHE BEST APPROACH FIGURE OUT HOW FREQUENTLY THE FIGURE OUT HOW FREQUENTLY THE

AREA HAS FLOODED IN THE PASTAREA HAS FLOODED IN THE PAST EXAMINE VEGETATIONEXAMINE VEGETATION FORMULATE A PLANFORMULATE A PLAN PROHIBIT CERTAIN BUILDING, ETC PROHIBIT CERTAIN BUILDING, ETC

ON FLOODPLAINON FLOODPLAIN