water's importance availability and renewal

1. Water’s Importance,Water’s Importance,
Availability and RenewalAvailability and Renewal

2. Daffy Duck in Aqua Duck
Montauk Shellfish Co. –
Montauk, NY

3. Core Case Study:Core Case Study:
The Colorado River StoryThe Colorado River Story
 Flows 2,300 km through seven U.S. statesFlows 2,300 km through seven U.S. states
 Includes 14 dams and reservoirsIncludes 14 dams and reservoirs
 Water supplied mostly from snowmelt of theWater supplied mostly from snowmelt of the
Rocky MountainsRocky Mountains
 Supplies water and electricity for about 30Supplies water and electricity for about 30
million peoplemillion people
 Las Vegas, Los Angeles, San DiegoLas Vegas, Los Angeles, San Diego
 Responsible for irrigation of crops that helpResponsible for irrigation of crops that help
feed Americafeed America

4. Core Case Study:Core Case Study:
The Colorado River StoryThe Colorado River Story
 IssuesIssues

Very little water isVery little water is
reaching the Gulfreaching the Gulf
of Californiaof California

The southwestThe southwest
has recently beenhas recently been
recent droughtsrecent droughts

5. WaterWater
 H+ bonded with OH- (covalent bonds) HH+ bonded with OH- (covalent bonds) H22OO
 Hydrogen bondsHydrogen bonds hold molecules togetherhold molecules together
 Properties:Properties:

Cohesion (similar molecules)Cohesion (similar molecules)

Adhesion (dissimilar molecules)Adhesion (dissimilar molecules)

ViscosityViscosity

Surface tensionSurface tension

DensityDensity

Heat capacityHeat capacity

Dissolving powerDissolving power

6. WATER’S IMPORTANCE,WATER’S IMPORTANCE,
AVAILABILITY, AND RENEWALAVAILABILITY, AND RENEWAL
 Functions of water:Functions of water:

Keeps us aliveKeeps us alive

Moderates climateModerates climate

Sculpts the landSculpts the land

Removes and dilutes wastes and pollutantsRemoves and dilutes wastes and pollutants

Moves continually through the hydrologic cycleMoves continually through the hydrologic cycle
 Covers 71% of earth, but only about 0.024%Covers 71% of earth, but only about 0.024%
of the earth’s water supply is available to usof the earth’s water supply is available to us
as liquid freshwateras liquid freshwater

Rest in oceans, ice caps and glaciers,Rest in oceans, ice caps and glaciers,
inaccessible groundwaterinaccessible groundwater

7. The Water CycleThe Water Cycle
Figure 3-26Figure 3-26
glaciers
aquifer

8. WATER’S IMPORTANCE,WATER’S IMPORTANCE,
AVAILABILITY, AND RENEWALAVAILABILITY, AND RENEWAL
 Water is a poorly managed resourceWater is a poorly managed resource
 Water is a renewable resource, but becomingWater is a renewable resource, but becoming
nonrenewablenonrenewable
 Water is a:Water is a:

Global health issueGlobal health issue

Economic issueEconomic issue

Children’s issueChildren’s issue

Women’s issueWomen’s issue

National and global security issueNational and global security issue

Environmental issueEnvironmental issue

9. WATER’S IMPORTANCE,WATER’S IMPORTANCE,
AVAILABILITY, AND RENEWALAVAILABILITY, AND RENEWAL
 Comparison ofComparison of
population sizes andpopulation sizes and
shares of the world’sshares of the world’s
freshwater amongfreshwater among
the continentsthe continents
 Water is distributedWater is distributed
unequallyunequally

10. WATER’S IMPORTANCE,WATER’S IMPORTANCE,
AVAILABILITY, AND RENEWALAVAILABILITY, AND RENEWAL
 About 2/3 of the world’s population facesAbout 2/3 of the world’s population faces
water scarcity for at least one month of thewater scarcity for at least one month of the
yearyear

11. WATER’S IMPORTANCE,WATER’S IMPORTANCE,
AVAILABILITY, AND RENEWALAVAILABILITY, AND RENEWAL
 GroundwaterGroundwater – water that infiltrates into the– water that infiltrates into the
ground and is stored in soil and rockground and is stored in soil and rock
 Surface waterSurface water – water that does not sink into– water that does not sink into
the ground or evaporate into the air – runs offthe ground or evaporate into the air – runs off
into bodies of waterinto bodies of water

12. GroundwaterGroundwater
 Zone of saturationZone of saturation – spaces between rock– spaces between rock
and soil filled with waterand soil filled with water
 Water tableWater table – top of zone of saturation – rises– top of zone of saturation – rises
and fallsand falls
 AquiferAquifer – underground layers that store water– underground layers that store water

ConfinedConfined – confined on top and bottom by– confined on top and bottom by
impermeable layer – rock or clayimpermeable layer – rock or clay

UnconfinedUnconfined – confined on bottom by– confined on bottom by
impermeable layerimpermeable layer

13. GroundwaterGroundwater
 RechargeRecharge – water that percolates through soil– water that percolates through soil
and rock – slowand rock – slow

Natural rechargeNatural recharge – water percolating downward– water percolating downward

Lateral rechargeLateral recharge – recharged from side– recharged from side
 Nonrenewable aquiferNonrenewable aquifer – gets little if any– gets little if any
rechargerecharge

14. Fig. 14-3, p. 308
Unconfined Aquifer Recharge Area
Precipitation Evaporation and transpiration Evaporation
Confined
Recharge
Area
Runoff
Flowing
artesian
well
RechargeRecharge
UnconfinedUnconfined
AquiferAquifer
Stream Well
requiring a
pumpInfiltration Water
table Lake
Infiltration
Unconfined aquifer
Confined aquifer
Confining impermeable rock layer
Confining impermeable rock layer
Less permeableLess permeable
material such as clay
material such as clay
Groundwater

15. GroundwaterGroundwater
 Artesian wellArtesian well – dug into a confined aquifer –– dug into a confined aquifer –
deeper – does not require pumping sincedeeper – does not require pumping since
water under pressurewater under pressure
 Water table wellWater table well – dug into unconfined– dug into unconfined
aquifer – shallower – requires pumping sinceaquifer – shallower – requires pumping since
water not under pressurewater not under pressure

16. Long Island GroundwaterLong Island Groundwater

17. GroundwaterGroundwater
 Ogallala AquiferOgallala Aquifer – world’s largest known– world’s largest known
aquifer – nonrenewable aquifer – gets littleaquifer – nonrenewable aquifer – gets little
recharge – seriously overdrawn due torecharge – seriously overdrawn due to
agricultureagriculture

18. Surface WaterSurface Water
 Water flowing across land surface – rivers,Water flowing across land surface – rivers,
streams, lakes, ponds, reservoirs, estuariesstreams, lakes, ponds, reservoirs, estuaries
 Replenished by runoff – precipitation, meltingReplenished by runoff – precipitation, melting
snow, and groundwater – does not infiltratesnow, and groundwater – does not infiltrate
 We currently use more than half of theWe currently use more than half of the
world’s reliable runoff of surface water andworld’s reliable runoff of surface water and
could be using 70-90% by 2025could be using 70-90% by 2025

19. Surface WaterSurface Water
 Watershed (drainage basin)Watershed (drainage basin) – the land from– the land from
which the surface water drains into a body ofwhich the surface water drains into a body of
waterwater

20. Water UsesWater Uses
 HydrologistHydrologist – scientist who studies water– scientist who studies water
movements above, on, and below earth’smovements above, on, and below earth’s
surfacesurface
 Reliable surface runoffReliable surface runoff – can count on from– can count on from
year to year – only 1/3 of runoff (the rest is lostyear to year – only 1/3 of runoff (the rest is lost
in flooding)in flooding)
 About 70% of water we withdraw from rivers,About 70% of water we withdraw from rivers,
lakes and aquifers is not returned to theselakes and aquifers is not returned to these
sources – evaporation, seepage, transport tosources – evaporation, seepage, transport to
other areas, contaminationother areas, contamination

Not destroyed, but returned elsewhereNot destroyed, but returned elsewhere

21. Water UsesWater Uses
 Uses:Uses:

Irrigation (70%)Irrigation (70%)

Industries (20%)Industries (20%)

Cities and residences (10%)Cities and residences (10%)
 Water footprintWater footprint – measure of freshwater– measure of freshwater
directly and indirectly used to support lifestylesdirectly and indirectly used to support lifestyles
– 92% agriculture– 92% agriculture
 American use – 69 gallons per day on avg.American use – 69 gallons per day on avg.

Toilets (27%), laundry (22%), showers (17%),Toilets (27%), laundry (22%), showers (17%),
running faucets (16%), leaks (14%)running faucets (16%), leaks (14%)
 Virtual waterVirtual water – indirect uses – make food and– indirect uses – make food and
other productsother products

23. L.A. Times Graphic:
How Much Water Was Used to
Make This Plate?