Water Resources
G. Tyler Miller’s
Living in the Environment
Supply of Water Resources
Freshwater
Readily accessible freshwater
Groundwater
0.592%
Biota
0.0001%
Lakes
0.0007%
Ice caps
and glaciers
1.5%
0.014%
Soil
moisture
0.0005%
Rivers
0.0001%
Atmospheric
water vapor
0.0001%
Use of Water Resources
 Humans use about 50% of reliable runoff
 Agriculture
 Industry
 Domestic
United States
Power
cooling
38%
Agriculture
38%
 Power plants
Industry 11%
Public 10%
Water use (cubic kilometers per year)
5,500
5,000
Total use
4,500
4,000
3,500
3,000
2,500
2,000
Agricultural use
1,500
Industrial use
1,000
Domestic use
500
1900
1920
1940
1960
Year
1980
2000
1 automobile
400,000 liters
(106,000 gallons)
1 kilogram
cotton
10,500 liters
(2,400 gallons)
1 kilogram
aluminum
9,000 liters
(2,800 gallons)
1 kilogram
grain-fed beef
7,000 liters
(1,900 gallons)
1 kilogram
rice
1 kilogram
corn
1 kilogram
paper
1 kilogram
steel
5,000 liters
(1,300 gallons)
1,500 liters
(400 gallons)
880 liters
(230 gallons)
220 liters
(60 gallons)
Too Little Water
Dry climate
Drought
Dessication
Acute shortage
Water stress
Adequate supply
Shortage
Metropolitan regions with
population greater than 1 million
Using Dams and Reservoirs to
Supply More Water
Flooded land destroys
forests or cropland and
displaces people
Large losses
of water through
evaporation
Downstream cropland and
estuaries are deprived of
nutrient-rich silt
Downstream flooding
is reduced
Reservoir is useful for
recreation and fishing
Can produce cheap electricity
(hydropower)
Migration and spawning of some fish are disrupted
Provides water
for year-round
irrigation of
cropland
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.
Dam Removal
• Some dams are being removed for ecological
reasons and because they have outlived their
usefulness.
– In 1998 the U.S. Army Corps of Engineers announced
that it would no longer build large dams and diversion
projects in the U.S.
– The Federal Energy Regulatory Commission has
approved the removal of nearly 500 dams.
– Removing dams can reestablish ecosystems, but can
also re-release toxicants into the environment.
Case Study: The California
Experience
• A massive
transfer of water
from water-rich
northern
California to
water-poor
southern
California is
controversial.
IDAHO
WYOMING
Dam
Aqueduct or
canal
Salt Lake City
Upper Basin
Denver
Grand Junction
UPPER
BASIN
Lower Basin
UTAH
NEVADA
Lake
Powell
Grand
Canyon
Las Vegas
COLORADO
Glen
Canyon Dam
NEW MEXICO
Boulder City
CALIFORNIA
Los
Angeles
ARIZONA
Palm
Springs
San
Diego
All-American
Canal
Albuquerque
LOWER
BASIN
Phoenix
Yuma
Mexicali
Gulf of
California
Tucson
0
100 mi.
0
150 km
MEXICO
Aral Sea
• The Aral Sea was once the world’s fourth
largest freshwater lake.
KAZAKHSTAN
2000
ARAL
SEA
1989
1960
UZBEKISTAN
TURKMENISTAN
Tapping Groundwater
Year-round use
No evaporation losses
Often less expensive
Potential Problems
Ground Water
Flowing
artesian well
Precipitation
Well requiring a pump
Evaporation and transpiration
Evaporation
Confined
Recharge Area
Runoff
Aquifer
Infiltration
Stream
Water table
Lake
Infiltration
Unconfined aquifer
Less permeable material
such as clay
Confined aquifer
Confirming permeable rock layer
Less than 61 meters (200 ft)
WYOMING
SOUTH DAKOTA
61-183 meters (200-600 ft)
More than 183 meters (600 ft)
(as much as 370 meters or 1,200 ft.
in places)
NEBRASKA
KANSAS
COLORADO
OKLAHOMA
NEW MEXICO
TEXAS
Miles
0
100
0
160
Kilometers
Problems with Using Groundwater
Water table lowering
Depletion
Subsidence
Saltwater intrusion
Chemical contamination
Reduced stream flows
Major irrigation
well
Well contaminated
with saltwater
Water
table
Sea Level
Salt
water
Fresh
groundwater
aquifer
Interface
Saltwater
Intrusion
Interface
Normal
Interface
Original
water table
Initial water table
Cone of
depression
Lowered
water table
Other Effects of Groundwater
Overpumping
• Sinkholes form
when the roof of an
underground cavern
collapses after
being drained of
groundwater.
Too Much Water: Floods
 Natural phenomena
 Aggravated by
human activities
 Renew and replenish
Reservoir
Dam
Levee
Floodplain
Flood
wall
Solutions: Achieving a More
Sustainable Water Future
Efficient irrigation
Water-saving technologies
Improving water management
Using Water More Efficiently
 Reduce losses due to leakage
 Reform water laws
 Improve irrigation efficiency
 Improving manufacturing processes
 Water efficient landscaping
 Water efficient appliances
Water Pollution
Thanks to Miller and Clements
Key Concepts
 Types, sources, and effects of water pollutants
 Major pollution problems of surface water
 Major pollution problems of groundwater
 Reduction and prevention of water pollution
 Drinking water quality
Types and Sources of Water
Pollution
Point sources
Nonpoint sources
Biological oxygen
demand
Water
Quality
Do (ppm) at 20˚C
Good
8-9
Slightly
polluted
6.7-8
Moderately
polluted
Heavily
polluted
Gravely
polluted
4.5-6.7
Below 4.5
Below 4
Pollution of Streams
 Oxygen sag curve  Factors influencing recovery
Types of
organisms
Clean Zone
Normal clean water organisms
(Trout, perch, bass,
mayfly, stonefly)
8 ppm
Decomposition Septic Zone
Zone
Trash fish
(carp, gar,
Leeches)
Fish absent, fungi,
Sludge worms,
bacteria
(anaerobic)
Recovery Zone
Trash fish
(carp, gar,
Leeches)
Concentration
Dissolved oxygen
Oxygen sag
Biological oxygen
demand
2 ppm
Direction of flow
Point of waste or
heat discharge
Time of distance downstream
Clean Zone
Normal clean water organisms
(Trout, perch, bass,
mayfly, stonefly)
8 ppm
Pollution of Lakes
 Eutrophication
 Slow
turnover
Thermal
stratification
Discharge of untreated
municipal sewage
(nitrates and phosphates)
Nitrogen compounds
produced by cars
and factories
Discharge of
detergents
( phosphates)
Discharge of treated
municipal sewage
(primary and secondary
treatment:
nitrates and phosphates)
Natural runoff
(nitrates and
phosphates
Manure runoff
From feedlots
(nitrates and
Phosphates,
ammonia)
Runoff from streets,
lawns, and construction
Lake ecosystem lots (nitrates and
nutrient overload
phosphates)
and breakdown of
chemical cycling
Runoff and erosion
Dissolving of
(from from cultivation,
nitrogen oxides
mining, construction,
(from internal combustion
and poor land use)
engines and furnaces)
Case Study: The Great Lakes
CANADA
Nipigon Bay
Thunder Bay
Jackfish Bay
Silver Bay
St. Mary’s R.
St. Lawrence R.
Spanish R.
St. Louis R.
MICHIGAN
Penetary Bay
Sturgeon Bay
WISCONSIN
MICHIGAN
MINNESOTA
IOWA
ILLINOIS
Saginaw
Niagara Falls NEW
Saginaw R.Bay Grand R.
System
Niagara R.
St. Clair R. Thames R.
Buffalo R.
Detroit R.
Rouge R.
Ashtabula R.
Raisin R.
Cuyahoga
R. PENNSYLVANIA
Maumee R.
Rocky R.
Black R.
INDIANA
OHIO
Great Lakes drainage basin
Most polluted areas, according to the Great Lakes Water Quality Board
“Hot spots” of toxic concentrations in water and sediments
Eutrophic areas
YORK
Groundwater Pollution: Sources
 Low flow rates
 Few
bacteria
 Cold temperatures
Waste lagoon,
pond, or basin
Hazardous
waste
injection
well
Buried gasoline
and solvent
tanks
Mining
site
Water
pumping
well
Pumping
well
Road
salt
Sewer
Landfill
Cesspoll,
septic
tank
Leakage
from faulty
casing
Unconfined freshwater aquifer
Groundwater
Confined freshwater aquifer
Groundwater flow
Confined aquifer
Discharge
Groundwater Pollution Prevention
Monitoring aquifers
Leak detection systems
Strictly regulating hazardous waste
disposal
Ocean Pollution
Industry
Nitrogen oxides from autos
and smokestacks; toxic
chemicals, and heavy
metals in effluents flow
into bays and estuaries.
Cities
Toxic metals and
oil from streets and
parking lots pollute
waters; sewage
adds nitrogen and
phosphorus.
Urban sprawl
Bacteria and
viruses from sewers
and septic tanks
contaminate shellfish
beds and close
beaches; runoff
of fertilization from
lawns adds nitrogen
and phosphorus.
Closed
beach
Construction sites
Sediments are washed into waterways,
choking fish and plants, clouding
waters, and blocking sunlight.
Farms
Run off of pesticides, manure, and
fertilizers adds toxins and excess
nitrogen and phosphorus.
Red tides
Excess nitrogen causes explosive
growth of toxic microscopic algae,
poisoning fish and marine mammals.
Closed
shellfish beds
Oxygen-depleted
zone
Toxic sediments
Chemicals and toxic metals
contaminate shellfish beds,
kill spawning fish, and
accumulate in the tissues
of bottom feeders.
Healthy zone
Clear, oxygen-rich waters
promote growth of plankton
and sea grasses, and support fish.
Oxygen-depleted zone
Sedimentation and algae
overgrowth reduce sunlight,
kill beneficial sea grasses,
use up oxygen, and degrade habitat.
Fig. 19.11, p. 489
Oil Spills
 Sources: offshore wells, tankers, pipelines and
storage tanks
 Effects: death of organisms, loss of animal
insulation and buoyancy, smothering
 Significant economic impacts
 Mechanical cleanup methods: skimmers and
blotters
 Chemical cleanup methods: coagulants and
dispersing agents
Solutions: Preventing and Reducing
Surface Water Pollution
Nonpoint Sources
Point Sources
Reduce runoff
Clean Water Act
Buffer zone
vegetation
Water Quality Act
Reduce soil erosion
Technological Approach: Septic
Systems
Require suitable soils and maintenance
Septic tank
Manhole (for
cleanout)
Nonperforated
pipe
Household
wastewater
Perforated
pipe
Distribution
box
(optional)
Drain
field
Vent pipe
Gravel or
crushed
stone
Technological Approach: Sewage
Treatment
Mechanical and biological treatment
Secondary
Primary
Bar screen
Grit
chamber
Settling tank
Aeration tank
Settling tank
Chlorine
disinfection tank
To river, lake,
or ocean
Raw sewage
from sewers
Sludge
(kills bacteria)
Activated sludge
Air pump
Sludge digester
Sludge drying bed
Disposed of in landfill or
ocean or applied to cropland,
pasture, or rangeland
Technological Approach: Advanced
Sewage Treatment
Removes specific pollutants
Effluent from
Secondary
treatment
Alum
flocculation
plus sediments
Desalination
Activated (electrodialysis
Nitrate
carbon or reverse osmosis) removal
98% of
suspended solids
90% of
phosphates
To rivers, lakes,
streams, oceans,
reservoirs, or industries
98% of
dissolved
organics
Recycled to land
for irrigation
and fertilization
Specialized
compound
removal
(DDT, etc.)
Most of
dissolved salts
Technological Approach: Using
Wetlands to Treat Sewage
(1) Raw sewage drains by
gravity into the first pool
and flows through a long
perforated PVC pipe into
a bed of limestone gravel.
(3) Wastewater flows through
another perforated pipe
into a second pool, where
the same process is repeated.
Sewage
Treated
water
Wetland type
plants
First concrete pool
Wetland type
plants
45 centimeter
layer of limestone
gravel coated with
decomposing bacteria
(2) Microbes in the limestone gravel
break down the sewage into
chemicals, that can be absorbed
by the plant roots, and the gravel
absorbs phosphorus.
Second concrete pool
(4) Treated water flowing from the
second pool is nearly free of
bacteria and plant nutrients.
Treated water can be recycled
for irrigation and flushing toilets.