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.

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

• 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

Fresh Water Sources

• Lakes ;stored water such as reservoirs

• Rivers: dams• groundwater

• Advantages of these sources: renewal

• Disadvantages of these sources: pollution

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

http://geopanorama.rncan.gc.ca/vancouver/sea_e.php?p=1

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