Water Resources

G. Tyler Miller’sLiving in the Environment

13th Edition

Chapter 14

Objectives:

Summarize the abundance and use of water.

Evaluate the advantages and disadvantages of dams.

Question:

How much water do you use on a daily basis (directly and indirectly)?

1430 gal/day (2000, http://pubs.usgs.gov/fs/2005/3051/)

Supply of Water Resources

Fig. 14-2 p. 314

Freshwater 2.6% Readily accessible freshwater

Biota0.0001%

Rivers0.0001%

Atmosphericwater vapor

0.0001%

Lakes0.0007%

Soilmoisture0.0005%

Groundwater0.592%

Ice capsand glaciers

1.984%

0.014%

Haves and have-nots

Surface Water

Surface runoff

Reliable runoff

Watershed (drainage basin)

Evaporation and transpiration

Evaporation

Stream

InfiltrationWater tableInfiltration

Unconfined aquifer

Confined aquifer

Lake

Well requiring a pump

Flowingartesian well

Runoff

Precipitation

ConfinedRecharge Area

Aquifer

Less permeable materialsuch as clay Confirming permeable rock layer

Ground WaterWater in soil/rock pores. WatertableAquifer Recharge - slow

Sioux Falls WaterWhere do we get our water?

Use of Water Resources Humans use about 50% of reliable runoff Increase use Distribution concerns United States

Industry 11%Public 10%

Powercooling

38%

Agriculture41%

5,5005,0004,5004,0003,5003,0002,5002,0001,5001,000

500

1900 1920 1940 1960 1980 2000Wat

er u

se (c

ubic

kilo

met

ers

per y

ear)

Total use

Agricultural useIndustrial use

Domestic use

Year

5,5005,0004,5004,0003,5003,0002,5002,0001,5001,000

500

1900 1920 1940 1960 1980 2000Wat

er u

se (c

ubic

kilo

met

ers

per y

ear)

Total use

Agricultural useIndustrial use

Domestic use

Year

Total use

Agricultural useIndustrial use

Total use

Agricultural use

Domestic use

Industrial use

Total use

Agricultural use

Too Little Water - CausesDry climateDrought Desiccation –

plant lossWater stress –

pop. growthAcute shortage

Adequate supply

ShortageMetropolitan regions with population greater than 1 million

Fig. 14-7 p. 317

Global ProblemsWater Stressed

– 1700m3/y/person

Water Scarcity – 1000m3/y/person

2.4-3.4 billionTiming & storage

Fig. 14-8 p. 318

High None

NorthAmerica

SouthAmerica Stress

Africa

Europe

Asia

Australia

Increase Supplies - Solutions?Reservoirs

Transfers

Groundwater

Desalination

ConserveImport Food

Dam Good!Capture and

store runoff.Control floodsPowerIrrigation and

domesticRecreation

Dam Bad!Reduce flow

Prevents all of these

• Deliver nutrients to the sea sustain coastal fisheries

• Deposit silt that maintains deltas

• Purify water

• Renew and nourish wetlands

• Provide habitats for aquatic life

• Conserve species diversity

Mission:

You are the supreme water dictator of the world. How do you come up with a solution to global water issues?

Objectives:

Summarize the abundance and use of water.

Evaluate the advantages and disadvantages of dams.