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Water Use and Management. Outline:. Water Availability and Use Freshwater Shortages Water Management and Conservation Privatization of water Water wars. WATER RESOURCES. Water, liquid and solid, covers more than 70% of world’s surface. More than 370 billion billion gallons.
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Water Use and Management Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Outline: • Water Availability and Use • Freshwater Shortages • Water Management and Conservation • Privatization of water • Water wars Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
WATER RESOURCES • Water, liquid and solid, covers more than 70% of world’s surface. • More than 370 billion billion gallons. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Hydrologic Cycle Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Sources of water Surface fresh water: 3% of liquid water, which is 13% of fresh water, which is 2.4% of water Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Groundwater • Second largest reservoir of fresh water. • Infiltration - Process of water percolating through the soil and into fractures and permeable rocks. • Zone of Saturation - Lower soil layers where all spaces are filled with water. • Water Table - Top of Zone of Sat. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Groundwater Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Groundwater • Aquifers - Porous layers of sand, gravel, or rock lying below the water table. • Artesian - Pressurized aquifer intersects the surface. (Water flows without pumping) • Recharge Zone - Area where water infiltrates into an aquifer. • Recharge rate is often very slow. • Presently, groundwater is being removed faster than it can be replenished in many areas. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Groundwater Aquifer Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Water diversions from rivers Yellow River (Huang He) In northern China Colorado River Delta in U.S./Mexico Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Diversion of rivers to the Aral Sea • Once the 4th largest inland body of water in the world A series of dams was built to irrigate cotton. • Aral Sea reduced to about 25% of its 1960 volume, quadrupled the salinity of the lake and wiped out the fishery. Pollutants became airborne as dust, causing significant local health problems. • The environmental damage caused has been estimated at $1.25 -$2.5 billion a year. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
U.S. Water Policy • Through most of US history, water policies have generally worked against conservation. • In well-watered eastern states, water policy was based on riparian use rights. • In drier western regions where water is often a limiting resource, water law is based primarily on prior appropriation rights. • Fosters “Use it or Lose it” policies. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Ogallala Aquifer High- capacity well withdrawals Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Dried-up reservoir Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Western U.S. water conflicts Klamath Basin, Oregon vs. Farmers. Ranchers. “Wise Users” Commercial fishers, Sport fishers, Tribes, Environmentalists Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Bulk water transfers River system diversions(Canada-to-U.S.)Water pipelines(Canada/Great Lakes-to-Southwest)Supertankers(North America-to-Asia)Canadian government banned bulk transfers in 1999. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Groundwater replenishing Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
WATER AVAILABILITY AND USE • Renewable Water Supplies • Made up of surface runoff and infiltration into accessible freshwater aquifers. • Readily accessible, renewable supplies are 400,000 gal/person/year. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Drought Cycles • Every continent has regions of scarce rainfall due to topographic effects or wind currents. • Water shortages have most severe effect in semiarid zones where moisture availability is the critical factor in plant and animal distributions. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Types of Water Use • Withdrawal - Total amount of water taken from a source. • Consumption - Fraction of withdrawn water not returned to its source. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Types of Water Use • Worldwide, humans withdraw about 10% of total annual renewable supply. • Many societies have always treated water as an inexhaustible resource. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Quantities of Water Used • Human water use has been increasing about twice as fast as population growth over the past century. • Average amount of withdrawn worldwide is about 170,544 gal/person/year. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Global Water Use Growth Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Precipitation Patterns Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Water use Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
FRESHWATER SHORTAGES • Estimated 1.5 billion people lack access to an adequate supply of drinking water. • Nearly 3 billion lack acceptable sanitation. • A country where consumption exceeds more than 20% of available, renewable supply is considered vulnerable to water stress. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
A Precious Resource • 45 countries have serious water stress, and cannot meet the minimum essential water requirements of their citizens. • More than two-thirds of world’s households have to retrieve water from outside the home. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Depleting Groundwater • Groundwater is the source of nearly 40% of fresh water in the US. • On a local level, withdrawing water faster than it can be replenished leads to a cone of depression in the water table, • On a broader scale, heavy pumping can deplete an aquifer. • Mining non-renewable resource. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Depleting Groundwater Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Depleting Groundwater • Withdrawing large amounts of groundwater in a small area causes porous formations to collapse, resulting in subsidence. • Sinkholes form when an underground channel or cavern collapses. • Saltwater intrusion can occur along coastlines Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Saltwater Intrusion Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Domestic Conservation • Estimates suggest many societies could save as much as half of current domestic water usage without great sacrifice or serious change in lifestyle. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Typical US Household Water Use Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
WATER WARS 12% of population uses 85% of water Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Price Mechanisms • Charging a higher proportion of real costs to users of public water projects has helped encourage conservation. • Yet discriminates against poor. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Global water Industry Over $140 Billion a year The World Water and Wastewater Utilities Market is estimated at $142 billion US in 2000… (2000, $US) Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Water multinationals Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Public/private water in EU countries Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Public and private prices in France Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
“Water War” in Bolivia Cochabamba residents protesting Bechtel privatization of municipal water system, 1999 Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Private and public: subsidies to and from water Private Public Subsidies from taxation Loss leaders Water services Financing other MNC operations Financing other public services Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Alternative: Porto Alegre, Brazil • Autonomous department • Efficiency and public accountability • ‘Participatory budgeting’ • Decentralised democratic prioritising Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Alternative: Debrecen, Hungary • Preferred public to private • Cheaper • Financial comparison Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Safety of municipal water supplies Australia, 1998 (privatized system) Wisconsin, 1993 Ontario, 2000 (gov’t had dropped e-coli testing) Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Bottled water costs more than oil Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Bottled water quality in question Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Bottled water growth Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.
Water Privatization Woodstock Riot 1999 Fewer bubblers in public buildings? Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.