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Fresh Water. Fresh Water. Only 3% of the water on earth is fresh water: Hydrologic cycle Shortages do occur Groundwater supplies can be exhausted Pollution of fresh water a growing concern Major transporter of diseases, cholera, intestinal and other water borne diseases. Use of Fresh Water.
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Fresh Water • Only 3% of the water on earth is fresh water: • Hydrologic cycle • Shortages do occur • Groundwater supplies can be exhausted • Pollution of fresh water a growing concern • Major transporter of diseases, cholera, intestinal and other water borne diseases
Use of Fresh Water • We require about 80 liters a day • per capita consumption varies… have and have nots
Problems • As global warming accelerates, evaporation from fresh water and ground water surfaces will increase • Areas will increase with water deficits • Marginal areas ; desertification • Irrigation needs
Lakes ;stored water such as reservoirs Rivers: dams groundwater Advantages of these sources: renewal Disadvantages of these sources: pollution Fresh Water Sources
Water Transfer, Storage and Conservation • Interbasin transfer: canals, dams • Groundwater ; Ogallala aquifer, US • Problems: • Reduce volume in river perhaps leads to increase temperatures, reduce wetland habitat impact on birds and fish • Examples: James Bay, Bennett Dam, Hoover Dam, Aswan Damm
Solving the Problem • Conservation: • Domestic • Agriculture – drip irrigation, mulching, crop planting to reduce run –off and evaporation
Fresh Water Pollution • Septic tanks • Storm drains • Landfills • Mine-tailings (acid wash drainage) local ex. Britannia Mines
Great Lakes • Dug out thousands of years ago by glacial action • Resemble oceans, contain a large percentage of Canada’s fresh water • Decline in water levels • Increase evaporation rates due to climate change (parts of lakes don’t freeze) • Industrial, urban, agricultural needs are greater than before (are greater than the watershed’s cycle of replenishment)
Waterways in Peril • Pollution • Enclosed water system (not flush readily) • Eutrophication • Accumulation of chemicals in the food chain • Industrial, urban, agriculture pollutants • Clean up difficult: • International: need cooperation • Lake bottom accumulation a problem • Treating sewage • Shipping m; foreign species • Concentration of industrial activity • Nimby syndrome
Solutions • Great Lakes • Line pits • Dispose of waste correctly • Upgrade sewage plants • Industry must comply (reduce acid rain) • Reduce agriculture pesticides (find safe alternatives) • Use incinerators to burn waste
Solutions for Fresh Water • Recycle programs: reduce garbage bound for landfill sites • Recycle engine oil, paint • No use of chemicals • Compost bin • Smart shopper • Share knowledge • Use biodegradable soap