3/11/2017. The Salt Water Planet. Fresh Water: A Potentially Renewable Resource Global Water Use

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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): Supply of Water Resources & The Hydrologic Cycle (good news) annual transfer rates in thousands of cubic kilometers (10 3 km 3 ) Water Pollution: general definition, analysis, source, major types of water pollution 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 All water Oceans and saline lakes 97.4% Fresh water Fresh water 2.6% Ice caps and glaciers 1.984% Readily accessible fresh water? Lakes 0.007% 0.014% Soil moisture 0.005% Freshwater Readily accessible freshwater? Fresh Water: A Potentially Renewable Resource Global Water Use Ice caps and glaciers 1.984% Groundwater 0.592% 0.014% Lakes 0.007% Soil moisture 0.005% Biota % Rivers % Atmospheric water vapor 0.001% Maps of US Rivers Groundwater accounts for ~ times as much water as in all lakes, rivers, atmosphere and soil Water use (cubic kilometers per year) 5,500 5,000 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1, Total use Agricultural use Industrial use Domestic use Year 1

2 Use of Water Resources in US US: highest per capita water use in the world: ~ gallons per person/day OR 500,000 gal/person/year United States Power cooling 38% Agriculture 41% Industry 11% Domestic 10% Fig. 13.5, p automobile cotton aluminum 10,500 liters (2,400 gallons) 9,000 liters (2,800 gallons) 400,000 liters (106,000 gallons) Unequal Distribution of Water Web Link / Read this: grain-fed beef 7,000 liters (1,900 gallons) rice 5,000 liters (1,300 gallons) corn 1,500 liters (400 gallons) paper 880 liters (230 gallons) 1Kg ~ 2.2Lbs steel 220 liters (60 gallons) WEB LINK: Challenges: Unequal Distribution of Water Storms & Floods: too much water Floods natural phenomena, replenish nutrients and groundwater Floods aggravated by human activities; removing vegetation logging, overgrazing of domesticated animals, forest fires, mining, destruction of marsh land ~39% of natural disasters deaths are caused by floods Ca Flood of 1862 A 43 day storm, began in Dec 1881 Occurs in Ca every years Inland lakes lasted for 6 months, Sacramento was underwater for over 3 months In Central Valley the lake was 300 long X 20 miles wide and 30 ft. deep ¼ of Ca economy destroyed >200,000 cattle drowned In St. Louis, the Mississippi remained above flood stage for 144 days between April 1 and September 30,

3 Recent History / Too Much Water STORM SURGES Feb 19th 2017, near Mount Rose Hurricane Andrew Soquel Ave Bridge, Santa Cruz, 1982 (looking toward Front Street) Bangladesh Cyclone, April 1991 ~~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 Mangrove Forests aggravates problems. Pajaro River flood, Ohio River Valley 1937 Ohio River Valley 3

4 Hurricane Katrina 8/29/05 Villahermosa City, Capital of Tabasco State Mexico Nov 2 nd 2007, >800,000 homeless and ~ 80% is underwater Pakistan Floods, July 2010 ~2,000 fatalities, >1,000,000 homeless June, 2008 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. ~3min ~45min 4

5 Super Typhoon Hiayan Philippines & Vietnam Nov 8-10th, 2013 Colorado September 9, dead, 1 missing >1 billion in damages TYPHOON MAYSAK APRIL 5TH, South Carolina 2015 South Carolina

6 What can we do? Establish a Floodplain Management Plan Research: develop frequency curve Zoning: rohibit certain types of buildings / activities in high risk zones Build artificial levees, embankments, flood control dams Construct floodways, allow water to flow through community with minimal damage Channelization: deepen, widen to allow more runoff Elevate or flood-proof buildings There is no 1 solution. Consider relocating? Too little water What 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. Web Link (Drought in Ca pics) 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 Mi 3 of fresh water stored underground. ~50% is in upper ½ mile Zone of aeration, saturation, water table 6

7 Ground Water Aquifers and Aquicludes Porosity and Permeability Zone of Recharge, Zone of Discharge and Artesian Conditions Sizable recharge area River Water moves ~meters/sec Groundwater Flow Rates vary: ~1mm 1 Km per day 7

8 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 Original water table Initial water table Cone of depression Ogallala Aquifer ~450,000km2 Named in 1898 after it s type locality in Ogallala Nebraska. SOUTH DAKOTA 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. WYOMING Deposition of material occurred between ~30 2 million yrs BP. Consists of coarse and fine grain sedimentary rock and sediments. NEBRASKA KANSAS COLORADO Most of the water came from melting of the last glacial max, 5,000 10,000 yrs ago. Provides drinking water for ~82% of people living within the area Between 1980 to present, rate of drop has decreased in areas due better irrigation, wind breaks, crop rotation, terracing. OKLAHOMA In 2000, irrigation withdrawals were ~17 billion gal/day! NEW MEXICO Less than 61 meters (200 ft) meters ( ft) More than 183 meters (600 ft) (as much as 370 meters or 1,200 ft. in places) Lowered water table TEXAS Kilometers Some areas have been rising. The Ogallala Aquifer 8

9 Groundwater Overdrafts: 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 / water conservation In Ca: ~17 million acre feet (afy) of water are pumped per year ( 1 acre foot ~ 325,851 gallons) ~1.3 million afy of overdraft per year Source SQWD Summary Advantages/ 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 9