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Water Resources. Access to Water. Health Issues Lack of water = leading cause of illness Economic Issues Decrease poverty, production of food & energy Women/Children Issues In developing countries, responsible. Access to Water. Security Issues Increased national/international tensions
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Access to Water Health Issues • Lack of water = leading cause of illness Economic Issues • Decrease poverty, production of food & energy Women/Children Issues • In developing countries, responsible
Access to Water Security Issues • Increased national/international tensions Environmental Issues • Excessive withdrawal • 0.024% readily available
Access to Water Hydrologic cycle collects, purifies, recycles water • Humans disrupt this cycle Globally there is plenty of water; it’s not distributed justly
Groundwater Zone of saturation • Subsurface spaces completely filled w/ H2O Water Table – boundary between zones of aeration and saturation Aquifers • Deeper, porous layers through which H2O flows Reliable Surface runoff – reliable source of H2O; about 1/3 of total runoff
Home, Industry, Agriculture Consumptive Use • Water is removed from a source and not returned Non-consumptive Use • Water is not removed or temporarily removed
Depletion and Diversion Groundwater depletion • Sinkholes happen Dikes, levees and dams divert and deplete • Regional conflicts • Ecosystem damage • Economic impact • Three Gorges Dam = world’s largest
Desalination Removal of salt from seawater • One method – hastens evaporation (distillation) • Method 2 – forcing H2O through a membrane filter
Agriculture Efficient technologies ( lining irrigation canals) Low-pressure spray irrigation (downward spray) Match crop to climate Selective breeding and genetic modification
Residential, Municipal, Industrial Install low-flow facets, showerheads, appliances Automatic dishwashers v. by hand Watering at night Match lawn plants with local precipitation (xeriscaping)
Residential, Municipal, Industrial Industry: use processes requiring less water Maintain water infrastructure Recycling wastewater Capture runoff and pump into aquifers
Economic Solutions Market-based strategies • Ending gov’t subsidies for inefficient practices • Let price reflect true cost of extraction Privatization = increased efficiency? Decentralize control Many believe marketing strategies alone would make water available only to the rich