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Water Resources. G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 14. Dr. Richard Clements Chattanooga State Technical Community College. Water’s Unique Properties. Hydrogen bonding. Liquid over wide temperature range. Changes temperature slowly.
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Water Resources G. Tyler Miller’s Living in the Environment 13th Edition Chapter 14 Dr. Richard Clements Chattanooga State Technical Community College
Water’s Unique Properties • Hydrogen bonding • Liquid over wide temperature range • Changes temperature slowly • High heat of evaporation • Great dissolving power • pH • Adhesion and cohesion • Expands when it freezes
Supply of Water Resources Freshwater Readily accessible freshwater Groundwater 0.592% Biota 0.0001% Lakes 0.0007% Rivers 0.0001% 0.014% Ice caps and glaciers 0.592% Soil moisture 0.0005% Atmospheric water vapor 0.0001% Fig. 14-2 p. 314
Surface Water • Surface runoff • Reliable runoff • Watershed • Drainage basin
Ground Water Flowing artesian well 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 Fig. 14-3 p. 315
Use of Water Resources United States Agriculture 38% Power cooling 38% Industry 11% Public 10% • Humans use about 50% of reliable runoff • Agriculture • Industry • Domestic • Power plants Fig. 14-5 p. 316
Too Little Water Acute shortage Adequate supply Shortage Metropolitan regions with population greater than 1 million • Dry climate • Drought • Dessication • Water stress Fig. 14-7 p. 317
Using Dams and Reservoirs to Supply More Water Downstream cropland and estuaries are deprived of nutrient-rich silt Flooded land destroys forests or cropland and displaces people Large losses of water through evaporation Downstream flooding is reduced Reservoir is useful for recreation and fishing Provides water for year-round irrigation of cropland Can produce cheap electricity (hydropower) Migration and spawning of some fish are disrupted Fig. 14-9 p. 319
Transferring Water from One Place to Another CALIFORNIA NEVADA UTAH Shasta Lake Sacramento River Sacramento North Bay Aqueduct San Francisco Fresno South Bay Aqueduct Colorado River Los Angeles Aqueduct ARIZONA California Aqueduct Central Arizona Project Los Angeles Phoenix San Diego Colorado River Aqueduct Tucson MEXICO • Watershed transfer • California Water Project • Central Arizona Project • James Bay Fig. 14-13 p. 323
Tapping Groundwater • Year-round use • No evaporation losses • Often less expensive • Potential Problems!
Problems with Using Groundwater • Water table lowering (See Fig. 14-15 p. 326) • Depletion (See Fig. 14-16 p. 326) • Subsidence (See Fig. 14-16 p. 326) • Saltwater intrusion (See Fig. 14-17 p. 328) • Chemical contamination See Case Study p. 327 • Reduced stream flows
Converting Salt Water to Fresh Water and Making it Rain • Distillation desalination • Reverse osmosis desalination • Desalination is very expensive • Cloud seeding
Using Water More Efficiently • Reduce losses due to leakage • Reform water laws • Improve irrigation efficiency (Fig. 14-18 p. 330) • Improving manufacturing processes • Water efficient landscaping • Water efficient appliances
Too Much Water: Floods • Natural phenomena • Aggravated by human activities • Renew and replenish Reservoir Dam Levee Flood wall Floodplain Fig. 14-22 p. 332
Solutions: Achieving a More Sustainable Water Future • Efficient irrigation • Water-saving technologies • Improving water management See Fig. 14-25 p. 336
Water Pollution G. Tyler Miller’s Living in the Environment 13th Edition Chapter 19 Dr. Richard Clements Chattanooga State Technical Community College
Types and Sources of Water Pollution Fig. 19-3 p. 485 • Point sources Refer to Tables 19-1 and 19-2 p. 484 and 485 • Nonpoint sources • Biological oxygen demand • Water quality
Point and Nonpoint Sources NONPOINT SOURCES Rural homes Cropland Urban streets Animal feedlot POINT SOURCES Suburban development Factory Wastewater treatment plant Fig. 19-4 p. 486
Pollution of Streams • Oxygen sag curve • Factors influencing recovery Fig. 19-5 p. 488
Pollution of Lakes Fig. 19-7 p. 491 • Eutrophication • Slow turnover • Thermal stratification
Case Study: The Great Lakes Fig. 19-8 p. 492
Groundwater Pollution: Sources • Cold temperatures • Low flow rates • Few bacteria Hazardous waste injection well Pesticides Coal strip mine runoff De-icing road salt Buried gasoline and solvent tank Cesspool septic tank Pumping well Gasoline station Waste lagoon Water pumping well Sewer Landfill Leakage from faulty casing Accidental spills Discharge Unconfined freshwater aquifer Confined aquifer Fig. 19-10 p. 494 Confined freshwater aquifer Groundwater flow
Groundwater Pollution Prevention • Monitoring aquifers • Leak detection systems • Strictly regulating hazardous waste disposal • Storing hazardous materials above ground
Ocean Pollution Fig. 19-12 p. 498
Case Study: Chesapeake Bay Fig. 19-14 p. 500 • Largest US estuary • Relatively shallow • Slow “flushing” action to Atlantic • Major problems with dissolved O2
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 Fig. 19-16 p. 504
Technological Approach: Sewage Treatment • Mechanical and biological treatment Fig. 19-17p. 504
Technological Approach: Advanced Sewage Treatment • Removes specific pollutants Fig. 19-18p. 505
Technological Approach: Using Wetlands to Treat Sewage Fig. 19-19p. 506
Drinking Water Quality Fig. 19-11 p. 495 • Bottled water • Safe Drinking Water Act • Maximum contaminant levels