Chapter 11: Water and Environment Big Question: Can We Maintain our Water Resources for Future Generations?
A Brief Global Perspective Growing global water shortage is linked to our food supply. The main process in cycle is global transfer of water.
The World's Water Supply (Selected Examples) Source: U.S. Geological Survey
Surface Water and Groundwater Surface water and groundwater are parts of the same resource.
Desalination Turning sea water into freshwater is getting less expensive, but still more than traditional water supplies in U.S. Desalinated water has a place value: the price rises depending on how far water must move from plant. Environmental impact of discharge
Overdraft Problem of overdraft - taking more groundwater than is naturally replaced
Transport of Water Moving water to where it is needed is not a new idea. New York City has imported water for over 100 years. Today a lot of water comes from upstate forests Catskills water was filtered effectively by natural processes.
New York City's Water Supply This natural service became overwhelmed by local development and pollution. New York City decided on sewage treatment rather than water treatment in the Catskills. Good water quality maintained by offering financial incentives to area’s farmers and homeowners Transporting water has its limits.
Domestic Use Source: Stilles_Mineralwasser.jpg
Wetlands Common feature: wet for part of year and have particular type of vegetation and soil. Wetlands include salt marshes, swamps, bogs, prairie potholes, and vernal pools.
Threats to Wetlands Freshwater wetlands are threatened. Over 50% of the wetlands in the US have disappeared. Salt marshes have also suffered (for example, the San Francisco Bay estuary). Redirecting the Mississippi is leading to loss of coastal wetlands.
Preserving and Restoring Wetlands • Offer incentives to wetlands owners • Related management issue is restoration of wetlands • Construct wetlands to clean up agricultural runoff • Creation of wetlands in Florida to help restore Everglades
Dams and the Environment Dam effects include • loss of land, cultural resources, and biological resources; • storage of sediment behind the dam; • fragmentation of river ecosystems; and • downstream changes in hydrology and in sediment transport.
Global Water ShortageLinked to Food Supply Isolated water shortages are indicators of a larger global pattern Surface and groundwater are being stressed and depleted: • groundwater is being used faster than it is renewed; • large water bodies are drying up (for example, the Aral Sea); and • large rivers are running dry before reaching the ocean.
Water Pollution Copy of 1958 poster advertising Metro bond campaign to clean up Lake Washington.
Water Reuse In Las Vegas, new resort hotels that use a great deal of water for fountains, rivers, canals, and lakes are required to treat wastewater and reuse it.
Chapter 11: Water and Environment Questions? E-mail your TA. email@example.com