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10/6/2016
1
• Distribution of water on earth, amount of fresh water available?
• U.S. water use, how much, what for
• Unequal Distribution: floods and scarcity
• Reasons for fresh water shortages?
• Some technological solutions to water shortages (Pros and Cons):
• Water Pollution: general definition, analysis, source, major types of water pollution
Supply of Water Resources &
The Hydrologic Cycle (good news)
annual transfer rates in thousands of cubic kilometers (103 km3)
The Salt Water Planet
• Oceans: 71% of Earths surface
• ~97.4% salt water
– Unusable for drinking, irrigation and most industry
• ~2.6% fresh water
– Ice
– groundwater
– surface water
~2.0% Ice Caps and Glaciers
Antarctica & Greenland Ice Sheet
All water Fresh water Readily accessible fresh water?
Oceans andsaline lakes97.4%
Fresh water2.6% Ice caps
and glaciers1.984%
Lakes0.007%
Soilmoisture0.005%
0.014%
Cool map of US Rivershttp://www.wired.com/design/2013/06/infographic-this-detailed-map-shows-every-river-in-the-united-states/?viewall=true
Groundwater accounts for ~ 35 – 55 times as much water as in all lakes, rivers, atmosphere and soil
Freshwater Readily accessible freshwater?
Biota0.0001%
Rivers0.0001%
Atmosphericwater vapor
0.001%
Lakes0.007%
Soilmoisture0.005%
Groundwater0.592%
Ice capsand glaciers
1.984%
0.014%
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Some Units of Water Measurement 5,500
5,000
4,500
4,000
3,500
3,000
2,500
2,000
1,500
1,000
500
1900 1920 1940 1960 1980 2000
Wa
ter
us
e (
cu
bic
kil
om
ete
rs p
er
yea
r)
Total use
Agricultural use
Industrial use
Domestic use
Year
Fresh Water: A Potentially Renewable ResourceGlobal Water Use 1900 ‐ 2000
Use of Water Resources in US
United States
Industry 11%
Domestic 10%
Powercooling
38%
Agriculture41%
Fig. 13.5, p. 298
US: highest per capita water use in the world: ~1280 - 1370 gallons per person/day…OR
500,000 gal/person/year
1 automobile
1 kilogramcotton
1 kilogramaluminum
1 kilogramgrain-fed beef
1 kilogramrice
1 kilogramcorn
1 kilogrampaper
1 kilogramsteel
400,000 liters(106,000 gallons)
10,500 liters(2,400 gallons)
9,000 liters(2,800 gallons)
7,000 liters(1,900 gallons)
5,000 liters(1,300 gallons)
1,500 liters(400 gallons)
880 liters(230 gallons)
220 liters(60 gallons)
1Kg ~ 2.2Lbs
WEB LINK:http://thegoodhuman.com/how-much-water-does-it-take/
Unequal Distribution of Water
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Challenges: Unequal Distribution of WaterStorms & Floods: too much water
• Floods are a natural phenomena, replenish nutrients and groundwater
• Floods aggravated by human activities; removing vegetation for urban development, improper logging, overgrazing of domesticated animals, forest fires, mining, destruction of marsh land……
• ~39% of natural disasters deaths are caused by floods
In St. Louis, the Mississippi remained above flood stage
for 144 days between April 1 and September 30, 1993.
Too Much Water / Fluvial Systems
Ca Flood of 1862
• A 43 day storm, began in Dec 1881
• Occurs in Ca every 100 – 200 years
• Inland seas lasted for 6 months, Sacramento was underwater for over 3 months
• In Central Valley the sea was 300 long X 20 miles wide and 30 ft. deep
• ¼ of Ca economy destroyed
• >200,000 cattle drowned
Recent History / Too Much Water Hurricanes, cyclones and storms bring waves and coastal flooding
STORM SURGES
Hurricane Andrew
Soquel Ave Bridge, Santa Cruz, 1982(looking toward Front Street)
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• ~~158 million ~138,000 killed, 10 million left homeless, storm surge height was
6 meters , 1.5 billion in damage
>157 million living in an are the size of Wisconsin.80% consists of floodplains.
Clearing of coastal MangroveForests aggravates problems.
Bangladesh Cyclone, April 1991 Pajaro River flood, 1995
1997Ohio River Valley
1937Ohio River Valley
Hurricane Katrina8/29/05
Villahermosa City, Capital of Tabasco State Mexico Nov 2nd 2007, >800,000 homeless and ~ 80% is underwater
June, 2008
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Pakistan Floods, July 2010~2,000 fatalities, >1,000,000 homeless
“Superstorm Sandy”October, 2012
In the United States, Hurricane Sandy affected 24 states, including the entire eastern seaboard from Florida to Maine and west across the Appalachia Mountains to Michigan and Wisconsin, with particularly severe damage in New Jersey and New York.
Its storm surge hit New York City on October 29, flooding streets, tunnels and subway lines and cutting power in and around the city. Damage in the United States amounted to over $68 billion.
https://www.youtube.com/watch?v=9QkBtxiowiA ~3min
https://www.youtube.com/watch?v=b1xkugQk4ck ~45min
Colorado September 9, 20138 dead, 1 missing>1 billion in damages
Super Typhoon HiayanPhilippines & Vietnam Nov 8-10th, 2013
TYPHOON MAYSAKAPRIL 5TH, 2015
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http://ulithimarineconservation.ucsc.edu/
South Carolina October 2015
South Carolina 2015
South Carolina 1903
http://floodlist.com/america/usa for 2016
So what can we do?
• Do research and develop frequency curve
• Prohibit certain types of buildings / activities in high
risk zones
• Build artificial levees / embankments, flood control dams
• Construct floodways that will allow water to flow through community with minimal damage
• Channelization: deepen, widen to allow > runoff
• Elevate or “flood‐proof” buildings
• There is no 1 solution…. Consider relocating?
Establish a Floodplain Management Plan
Too little waterWhat causes fresh water shortages?
•Water Stress or Scarcity: insufficient water to satisfy normal requirements, a relationship between demand and availability.
•Dry Climate
•Drought: A prolonged period where a region receives below average precipitation. A normal, recurring feature of most climates. Or for Santa Cruz Sandy Lydon says: We need to rewrite the sentence describing our typical weather: "A perpetual and persistent drought occasionally interrupted by unpredictable and sometimes excessive winter rains. But only occasionally”
•http://droughtmonitor.unl.edu/ Web Link
•http://www.businessinsider.com/photos-of-california-drought-2014-2#ixzz2vJWFBwFP (Drought in Ca pics)
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How can we increase freshwater supplies for a growing human population?
6 Technological Solutions to “Water Scarcity” or shortages
1. Extract Groundwater
2. Build Dams and Reservoirs to store runoff
3. Bring in surface water from other areas: Watershed Transfer
4. Desalination
5. IPR (Indirect Potable Reuse)
6. Improve Efficiency of Water Use~2 million Mi3 of fresh water stored underground. ~50% is in upper ½ mile
Zone of aeration, saturation , water table
Ground WaterAquifers and Aquicludes Porosity and Permeability
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Zone of Recharge, Zone of Discharge and Artesian Conditions
River Water moves ~meters/secGroundwater Flow Rates vary: ~1mm – 1 Km per day
How much groundwater is moving?Q=KIA, or Q=K*Head*A, or Q=K*Rise/Run* Area
K=permeability coefficient or “hydraulic conductivity" , Zone of Discharge, Flow Rates and Artesian Conditions
Cone of Depression
Cone of Depression
Initial water table
Cone ofdepression
Originalwater table
Loweredwater table
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Ogallala Aquifer~450,000km2
holds ~3,608 Km3
In some places, water is pumped
out 8 – 10 times faster than
recharge rate.
~30% of all ground water
used for irrigation in US.
Provides drinking water for ~82% of
people living within the area
In 2000, irrigation withdrawals
were ~17 billion gal/day!
WYOMING
SOUTH DAKOTA
NEBRASKA
COLORADOKANSAS
OKLAHOMA
NEW MEXICO
TEXAS0 100
Kilometers
Less than 61 meters (200 ft)
61-183 meters (200-600 ft)
More than 183 meters (600 ft)(as much as 370 meters or 1,200 ft.in places)
0 160
Named in 1898 after it’s
“type locality” in Ogallala Nebraska.
Deposition of material occurred
between ~30 – 2 million yrs BP.
Consists of coarse and fine grain
sedimentary rock and sediments.
Most of the water came from melting of the last glacial max, 5,000 – 10,000 yrs ago.
Between 1980 to present, rate of drop has decreased in areas due better irrigation, wind breaks, crop rotation, terracing.
Some areas have been rising.
The Ogallala Aquifer
GroundwaterOverdrafts:
High
Moderate
Minor or none
Subsidence:
High
Moderate
Minor or none
Salt Water Intrusion
• Often problematic in coastal aquifers
– Rate of pumping > rate of recharge
– Inland water table drops
– Seawater begins to fill in voids
– Solutions?: dig deeper wells, move well locations, watershed transfer or find other source, use less water? In Ca: ~17 million acre feet of water are pumped per year (afy)
( 1 acre foot ~ 325,851 gallons) ~1.3 million afy of overdraft Source SQWD
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SummaryAdvantages / Disadvantages of Extracting Groundwater
• Year round use
• Provides drinking water for over 2 billion people, >1 billion people in Asia
• No evaporation, responds less to dry seasons
• Often less expensive to develop than surface water systems
• Potential problems caused by overuse
– Water table lowering, “overdraft”, increases cost to
“mine” aquifers
– Crustal or “Fluid Loss” subsidence
– Chemical contamination of groundwater
– Reduced stream flow
– Salt water intrusion