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GLG110 Geologic Disasters


Water Line showing original lake level. Lake Powell loses 6% of the Colorado's annual ... hundreds of thousands of gallons from their allotment until new deal made ... – PowerPoint PPT presentation

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Title: GLG110 Geologic Disasters

GLG110 Geologic Disasters the Environment
Chapter 10 Water Resources
Instructor Professor Stan Williams Email
TA Carol Butler Email
Course Website http//
Term Project
  • Reflect on what you are learning about Geologic
    Disasters and the Environment
  • Worth
  • 100 points (20 of your total grade)
  • Due
  • Tuesday Nov 25 (before Thanksgiving break)

Term Project
  • Choose one of the following two topic areas and
    prepare a written report
  • Hometown Hazard
  • Examination of single large geologic disaster
  • Final paper must be
  • your original words
  • typed
  • double-spaced
  • 3-6 pages in length
  • fully referenced
  • include one figure

Refer to handout or class website (Announcements)
for details
  • Final Comments Floodplains
  • Water Use (and Misuse)
  • Colorado River
  • Drought
  • Water Management Future Prospects
  • Water Ecosystems

Humans and Floodplains
  • At least 9.6 million households and 390 billion
    in property lie in flood prone areas in the US.
  • The rate of urban growth in floodplains is
    approximately 2x that of the rest of the country.

Water Facts
  • 99 of Earths water is unavailable or unsuitable
    for human use
  • Put all the world's water into a
  • gallon jug, the fresh water equals
  • about one tablespoon
  • Global freshwater usage
  • 69 used for agriculture,
  • 23 industry
  • 8 municipal use by us

Portland, Oregon
Image US Fish Wildlife Service
U.S. Freshwater Use Misuse
  • The U.S. consumes water 2x the rate of other
    industrialized nations
  • Flush 6.8 billion gallons down toilets every day
  • The average home uses
  • 80 gallons per person each winter day
  • 120 gallons in summer
  • 2/3 of the average family's water- shower, bath
    and the toilet
  • 39,090 gallons to make a car

Water Use in Agriculture
  • 6 gallons to grow 1 serving of lettuce
  • gt 2,600 gallons to produce 1 serving of steak
  • 49 gallons to produce 1 - 8 oz. glass of milk
  • Average American consumes 1,500 pounds of food
    each year
  • 1,000 gallons to grow and process each pound
  • 1.5 million gallons invested in food of 1 person

Urban vs. Agriculture
  • only 1 of the water used around the house
    accounts for of the all water used in U.S. each
  • 80 of water used in the U.S. is for irrigating
    crops and generating electric-power

Image Fairview Farms, Corwith, Iowa
Water Resources
  • What do you observe about these two environments?
  • Where in the US are they likely to be found?
  • Should the populations observe different plans
  • for water usage and conservation?
  • Why or why not?

Water in the West
Image Larry Ridenhour / BLM
  • Water use in the West is much higher than in any
    other region
  • 2/3 Californias surface runoff occurs north of
  • San Francisco
  • 2/3 of Californias water use occurs south
  • Water diversion has altered ecosystems and

Idaho 22,200 gallons/day
152 gallons/day in Rhode Island
Image Rhode Island Tourism Division
Colorado River Watershed
  • All (and then some) of the water in Colorado
    River allocated to users, unlike that of any
    other river in the world
  • Annual flow 3 of the Mississippi, 1/10 of the
  • Vast areas are unpopulated,
  • water exported
  • One of the most regulated, controversial, and
    disputed bodies of water in the world

Colorado River Watershed
  • Watershed 246,000 square miles
  • Water for 7 states
  • Mexico
  • Starts as snow melt
  • in Wyoming
  • Flows to
  • Sea of Cortez
  • Average rainfall
  • in basin 4 inches or less

Dams on the Colorado River
  • Pre-Glen Canyon Dam
  • Max flow May or June
  • High flow scoured channel, cleared rapids, built
    and scoured beaches
  • Low flow deposited sediments in canyon
  • Numerous archaeological sites

Image Glen Canyon Institute
Dams on theColorado
  • Post-Dam
  • Average flood reduced 66
  • Discharge increased 66
  • Flow unstable due to power needs
  • Sediment flow halted, beaches and sandbars in
    canyon and associated habitats eroding
  • Rapids more dangerous
  • Changes in flow caused vegetation shifts
  • Loss of archaeological sites

Image Outdoors Unlimited
Image Outdoors Unlimited
Dams on the Colorado
  • Lake Powell loses gt 6 of the Colorado's annual
  • more than 3x Nevada's annual allotment
  • worth 225 million

Water Line showing original lake level
  • Since 1963,
  • water lost from Lake Powell
  • worth 8.8 billion

What a nasty bathtub ring!
1996 Controlled Flood
Images Northern Arizona State University
  • Experiment to attempt partial recovery of canyon
  • Sand in canyon non-renewable due to dam
  • Controlled floods will not return river to
    natural state

Sandbar downstream from Glen Canyon Dam before
controlled flood
Same location after flood
Environmental Impacts of Dams
  • Salton Sea created by breakout flood, now a water
    fowl habitat, evaporation increasing salinity
  • Rarely reaches Sea of Cortez only salt flat at
    river's mouth

US-Mexico Border
Note the healthier vegetation (red color) north
of the border, due in large part to more water
Salt Flat
Colorado River Water Cities
  • 10 major dams and 80 major diversions
  • 25 million people depend on rivers water
  • 30 million depend on electricity
  • from hydropower
  • Cities using Colorado River
  • water include Phoenix, Tucson,
  • Salt Lake City, Denver,
  • Albuquerque, San Diego,
  • Las Vegas, L.A., etc.

Colorado River Agriculture
  • gt 1.75 million acres of irrigated land produces
  • 15 of the nation's crops
  • 13 of its livestock, and
  • agricultural benefits of more than 1.5 billion a
  • In Arizona, 25 of the state's water is provided
    by the Colorado
  • 80 of that is used for agriculture

Images CRWUA
Law of the WestPrior Appropriation
  • Artifact of the California Gold Rush
  • first in time, first in right
  • Result emotional legal battles
  • does not consider which users have more valuable
    or less environmentally damaging use
  • does not consider how much water is (or is NOT)

Image Rhett Butler
Legal History
  • 1922 Colorado River Compact split western states
    into upper and lower basin, dividing Colorado
    River water equally between them
  • Compact requires upper basin states to produce
    7.5 million acre-feet of water each year
  • Problem - when the deal was worked out, it was a
    high-water year, amount of water in the river was
    hugely overestimated

Over-Promised, Over-Committed Overdrawn
  • In 1869, John Wesley Powell scouted and surveyed
    the river
  • there is not sufficient water to irrigate all
    the lands which could be irrigated
  • He developed thoroughly researched plan to
    regulate water use in west
  • Congress thought plan too restrictive, launched
    massive dam projects

Water Wars
  • Colorado produces 70 of the water in the whole
    river, but has entitlement smaller than
    Californias, which contributes no water to river
  • Ongoing drought in Colorado reducing water
  • California's allotment of Colorado River water is
    4.4 million acre feet, but it currently takes an
    extra 800,000 acre feet

Imperial Valley Renegotiation
  • July 2002, U.S. Bureau of Reclamation declared
    that Imperial Valley farmers were wasting water
    on their desert fields withheld hundreds of
    thousands of gallons from their allotment until
    new deal made
  • 400 farmers in California's Imperial Valley use
    70 the state's share of the river
  • Why do they use so much?

Image Darrell Byrd
Imperial Valley Renegotiation
  • (Left) This is what the Imperial Valley looked
    like in 1856
  • With the All American canal (below left)
    funneling water from the Colorado River, the
    Valley is now filled with farms

United States Pacific Railroad Exploration and
Survey, 1856
Mountains look familiar? Think Arizona desert!
Image James E. Kuhn
Image James E. Kuhn
Disaster of the Day Californias New Deal
  • Cornerstone - Imperial District will transfer up
    to 200,000 acre-feet a year to urban San Diego
    and possibly another 1.6 million acre-feet to
    Metropolitan District
  • Broader agreement aimed at easing California's
    overdependence on the river so other western
    states can claim their full share
  • Some provisions to help protect Salton Sea
  • Oct 7 vote by Imperial Valley board uncertain
    outcome, much opposition (watch the news tonight!)

  • Drought periods in which precipitation is much
    lower and evaporation much higher than normal
    (often because of higher than normal
  • Effects intensified by
  • Deforestation
  • Overgrazing
  • Desertification
  • Replacing diverse natural grasslands with single
    crop fields

  • Causes more damage and suffering worldwide than
    any other natural hazard
  • Since from 1970s through 1995 drought killed
    gt24,000 per year
  • 40 of worlds population live in regions that
    experience year long droughts
  • Effects will intensify with global warming

Dust Bowl
  • 1926-1934
  • Natural soil lost due to
  • poor cultivation practices
  • overgrazing
  • drought (began 1926)
  • Wind storms darkened the sky at midday
  • Animals choked to death on dust
  • Topsoil over cropland equal in area to
    Connecticut and Maryland was stripped

Image U.S. National Archives
Dust Bowl
  • Many forced to relocate but depression added to
  • Lawmakers in Washington took action when dust
    from Great Plains began infiltrating the hearing
  • 1935 established Soil Conservation Service

Image U.S. National Archives
Dust Bowl
  • Today Groundwater under area is being depleted
    faster than being replenished
  • Global warming could increase the desertification
    in progress
  • Area is better suited to grazing than farming

Image U.S. National Archives
Future Freshwater Resources
  • By 2025, 2/3 of the world's population will have
    water shortages
  • Today- 40 of worlds population clashes over
    water resources
  • Today- most of the world's people must walk at
    least 3 hours to fetch water
  • Freshwater animals are disappearing five times
    faster than land animals

Future Water Management
  • Locate alternate supplies (for example
  • Conserve and manage existing supplies
  • Control population growth and land-use

Alternate Sources Desalination
  • Seawater contains 3.5 salt
  • Drinkable water must be lt0.05
  • To remove salt requires large amounts of energy
    which causes its own depletion of natural
  • Water from desalination plants costs 10x current
  • not a viable option until other resources
  • By that time, the world supply of petroleum will
    be severely depleted

Water Conservation - Urban
  • Home
  • More efficient bathroom/sink fixtures
  • Water lawns and gardens at night
  • Use drip irrigation systems on lawns and gardens
  • Industry
  • Use cooling towers, reduce water use 25-30
  • Increase in plant water treatment recycling
  • Develop equipment that uses less water

Water Conservation - Agricultural
  • Improved agricultural irrigation (reduce
    withdrawals 20-30)
  • Use lined and covered canals (reduce seepage and
  • Computers to monitor water release in canals
  • Night irrigation (reduce evap)
  • Drip irrigation

Drip Pipes
Hidden Drip Pipes
Water Management
  • Must consider
  • geological
  • geographical
  • climatic factors
  • PLUS political
  • and economical matters
  • Plan ahead, have different use strategies based
    on climate cycles

Positive Trends in Water Use
  • Water withdrawals declining since 1980
  • Public use of water in urban and rural sectors
    has increased
  • Use of water in agriculture leveled off since
  • Industry and power water use slightly less since
  • More use of reclaimed wastewater

Water Ecosystems
Image US Fish Wildlife Service
  • Wetlands regions that are frequently inundated
    by water

Everglades National Park, Florida
Cypress Creek National Wildlife Refuge, Illinois
  • specially adapted vegetation and unique soils

Image QT Luong/
Environmental Features of Wetlands
  • Coastal wetlands (salt marshes) buffer inland
    areas from wave and storm erosion
  • Trap sediments, nutrients, and pollution
  • Store water, reduce downstream flooding

Image Chincoteague National History Association
Environmental Features of Wetlands
Everglades National Park, FL
  • Highly productive lands
  • cycle many nutrients and chemicals
  • Habitat for wide variety of plants and animals
  • Areas of groundwater recharge or discharge

Everglades National Park, FL
U.S. Wetlands at Risk
  • Most coastal wetlands are protected
  • Freshwater wetlands still threatened
  • 1 of wetlands lost every 2 years
  • In last 200 years, 90 of freshwater wetlands
    disappeared as result of agricultural draining or
    urban development
  • Areas cleared of riparian vegetation in the
    Midwest have erosion rates of 15 to 60 tons/ year

Wetlands Restoration
Images EPA
  • Not easy due to complex ecosystems and conditions

Gila River Watershed Arizona / New Mexico
Wetlands Restoration
Bear Creek Watershed Iowa
Images EPA
Mangroves, Everglades National Park, FL
Whiskey is for drinking and water is for
fighting over. Mark Twain
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