QOD Calculate how many liters of water are wasted in 1 month by a faucet that leaks 2 drops of water per second. (1 liter of water equals about 3500 drops) How many gallons is this? (1 liter equals 0.265 gallons)

1
QODCalculate how many liters of water are wasted
in 1 month by a faucet that leaks 2 drops of
water per second.(1 liter of water equals about
3500 drops)How many gallons is this?(1 liter
equals 0.265 gallons)
2
Water Resources
G. Tyler Millers Living in the Environment 13th
Edition Chapter 14
3
Key Concepts

• The physical properties of water

• Availability of fresh water

• Methods of increasing freshwater supplies

• Using water more efficiently

• Problems associated with flooding

4
Waters Unique Properties

• Hydrogen bonding
• Major factor in determining waters unique
  properties

5
Hydrogen bonds
Covalent bonds
6
Waters Unique Properties

• Liquid over wide temperature range
• High boiling point 100C (212F)
• Low freezing point 0C (32F)
• Changes temperature slowly
• Helps protect organisms
• Moderates the earths climate
• Excellent coolant
• High heat of evaporation
• Absorbs heat as it changes into water vapor
• Releases heat as vapor condenses

7
Waters Unique Properties

• Great dissolving power
• Carries dissolved nutrients into tissue
• Flush waste products out of tissue
• All-purpose cleanser
• Remove and dilute water-soluble wastes
• pH
• Helps maintain balance between acids and bases
• Adhesion and cohesion
• Surface tension
• Wetting ability
• Expands when it freezes
• Ice floats

8
Water A Vital Resource
Fresh Water 2.6
Oceans and saline lakes 97.4
9
Supply of Water Resources
10
Surface Water

• Surface runoff
• Water flowing off the land into bodies of water
• Reliable runoff
• One-third of worlds annual runoff
• Represents a stable source of water
• Watershed (Drainage Basin)
• Region from which water drains

11
Groundwater
12
Ground Water
Fig. 14-3 p. 315
Flowing artesian well
Unconfined Aquifer Recharge Area
Precipitation
Evaporation and transpiration
Well requiring a pump
Evaporation
Confined Recharge Area
Runoff
Aquifer
Stream
Infiltration
Water table
Lake
Infiltration
Unconfined aquifer
Confined aquifer
Less permeable material such as clay
Confirming permeable rock layer
13
Use of Water Resources

• Humans use about 50 of reliable runoff

• Agriculture
• Industry
• Domestic
• Power Plants

14
Total use
Agricultural use
Industrial use
Domestic use
Year
15
Water in the United States

• Average precipitation (top) in relation to
  water-deficit regions and
• their proximity to metropolitan areas (bottom).

16
Too Little Water

• Dry climate
• Air circulation patterns
• Drought
• 21 days
• Precipitation lt70
• Increased evaporation
• Desiccation
• Drying of the soil
• Water stress
• Low per capita availability
• Caused by increased population
• Limited runoff levels

17

• Water stressed reliable runoff per person below
  1700 cu meters per year

• Water scarcity per capita availability below
  1000 cu meter per year

• 500 million people live in countries that are
  either water stressed or water scarce
• limited access (live far away)
• arrives during short periods
• hydrological poverty
• Collect water from unsafe sources
• Purchase from private vendor

18
Increasing Fresh Water Supplies

1. Build dams and reservoirs to store runoff
2. Bring surface water from another area
3. Withdraw groundwater.
4. Convert salt water to fresh water
5. Waste less water
6. Import food to reduce water use

19
Using Dams and Reservoirs to Supply More
Water(To Dam or Not To Dam)
20

Provides water for year-round irrigation of
cropland
Flooded land destroys forests or cropland and
displaces people
Large losses of water through evaporation
Provides water for drinking
Downstream cropland and estuaries are deprived of
nutrient-rich silt
Reservoir is useful for recreation and fishing
Risk of failure and devastating downstream
flooding
Can produce cheap electricity (hydropower)
Downstream flooding is reduced
Migration and spawning of some fish are disrupted
Fig. 14-13a, p. 317
21
Ecological Services of Rivers
Deliver nutrients to the sea which helps to
sustain coastal fisheries Deposit silt that
maintains deltas Purify water Renew and
nourish wetlands Provide habitats for aquatic
life Conserve species diversity
22
Beijing
RUSSIA
YELLOW SEA
MONGOLIA
CHINA
Shanghai
Wunan
Jailing River
Yichang
Chongquing
Yangtze River
CHINA
Three Gorges Dam
Reservoir
EAST CHINA SEA
NEPAL
BHUTAN
BANGLADESH
PACIFIC OCEAN
VIETNAM
INDIA
BURMA
LAOS
Chinas Three Gorges Dam
23
Case Study The Colorado Basin an Overtapped
Resource

• Lake Powell, is the second largest reservoir in
  the U.S.
• It hosts one of the hydroelectric plants located
  on the Colorado River.

24
IDAHO
WYOMING
Dam
The Colorado River Basin
Aqueduct or canal
Salt Lake City
Grand Junction
Upper Basin
Denver
Lower Basin
UPPER BASIN
UTAH
COLORADO
Lake Powell
Grand Canyon
Glen Canyon Dam
Las Vegas
NEW MEXICO
Boulder City
ARIZONA
CALIFORNIA
Albuquerque
LOWER BASIN
Los Angeles
Palm Springs
Phoenix
0
100 mi.
San Diego
Yuma
0
150 km
Mexicali
Tucson
All-American Canal
MEXICO
Gulf of California
25
Transferring Water from One Place to Another
Watershed transfer

• California Water Project
• Central Arizona Project
• James Bay (Canada)

26
Increasing Fresh Water Supplies

1. Build dams and reservoirs to store runoff
2. Bring surface water from another area
3. Withdraw groundwater.

27
Tapping Groundwater

• Advantages
• Year-round use
• No evaporation losses
• Often less expensive
• Potential Problems!
• Many

28
Problems with Using Groundwater

1. Water Table Lowering

29
Problems with Using Groundwater

• Aquifer depletion
• Ogalala Aquifer

30
Problems with Using Groundwater

• Subsidence
• Sinking of land when groundwater is withdrawn

31
Other Effects of Groundwater Overpumping

• Sinkholes form when the roof of an underground
  cavern collapses after being drained of
  groundwater.

32
Problems with Using Groundwater

1. Saltwater intrusion

33

Major irrigation well
Well contaminated with saltwater
Water table
Sea level
Fresh groundwater aquifer
Saltwater
Seafloor
Interface
Saltwater intrusion
Interface
Normal interface
Fig. 14-11, p. 315
34
Problems with Using Groundwater

• Chemical contamination
• Reduced stream flow
• Tragedy of the commons

35
Converting Salt Water to Fresh Water

• Desalination removing dissolved salts from
  ocean water or brackish water.
• Distillation desalination
• Heating salt water until it evaporates.
• Reverse osmosis desalination
• Salt water is pumped at high pressure through a
  thin membrane

36
Converting Salt Water to Fresh Water

• Desalination removing dissolved salts from
  ocean water or brackish water.
• Desalination is very expensive
• Larger amounts of energy needed
• Desalination produces large quantities of
  wastewater
• waste disposal problem

37
Making it Rain

• Cloud Seeding
• Water condensation nuclei
• Silver iodide particles
• Limited Success
• Not useful in dry areas
• Potential pollution from cloud seeding chemicals
• Legal disputes ownership of clouds

38
Using Water More Efficiently

• Reduce losses due to leakage
• 60 to75 of water people use is lost!
• Causes of waste
• Water subsidy policy
• Artificially low cost of water
• False sense of abundance

39
Using Water More Efficiently

• Causes of waste cont.
• Water laws
• Doctrine of riparian rights (East)
• Anyone owning land adjoining stream has right to
  water
• Principle of prior appropriation (West)
• First-come, first-served
• Common law governs groundwater
• Subsurface water belongs to whoever owns the land
  above it
• Fragmented watershed management

40

Drip irrigation
(efficiency 9095)
Gravity flow
(efficiency 60 and 80 with surge valves)
Center pivot
(efficiency 8095)
Water usually pumped from underground and sprayed
from mobile boom with sprinklers.
Above- or below-ground pipes or tubes deliver
water to individual plant roots.
Water usually comes from an aqueduct system or a
nearby river.
Fig. 14-18, p. 325
41
Too Much Water Floods

• Natural phenomena
• heavy rain, melting snow

• Aggravated by human activities

• Renew and replenish

Reservoir
Dam
Levee
Flood wall
Floodplain
42
Solutions Achieving a More Sustainable Water
Future

• Efficient irrigation

• Water-saving technologies

• Improving water management

43

What Can You Do?
Water Use and Waste
Use water-saving toilets, showerheads, and
faucet aerators.
Shower instead of taking baths, and take short
showers.
Stop water leaks.
Turn off sink faucets while brushing teeth,
shaving, or washing.
Flush toilets only when necessary.
Wash only full loads of clothes or use the
lowest water-level for smaller loads.
Use recycled (gray) water for lawn, gardens,
house plants, car washing.
Wash a car from a bucket of soapy water, and
use the hose for rinsing only.
If you use a commercial car wash, try to find
one that recycles its water.
Replace your lawn with native plants that need
little if any watering and decorative gravel or
rocks.
Water lawns and gardens in the early morning or
evening.
Sweep or blow off driveways instead of hosing
off with water.
Use drip irrigation and mulch for gardens and
flowerbeds.
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2002 Free Response Question 2