Presentation on theme: "Conflict over water resources: Case study Colorado River Basin LO: explain how the water is being managed in the Colorado River basin."— Presentation transcript:
Conflict over water resources: Case study Colorado River Basin LO: explain how the water is being managed in the Colorado River basin
Water scarcity hotspots According to the International Water Management Institute environmental research organisation global water stress is increasing, and 1/3 rd of all people face some sort of water scarcity. Agricultural uses dominate in the growing need for food. Little/no water scarcity Physical water scarcity- not necessarily dry areas but those where over 75% river flows are used by agriculture, industry or domestic consumers Economic water scarcity- less than 25% rivers used, and abundant supply potential but not reaching the poorest people. Approaching physical water scarcity – More than 60% river flows allocated, and in the near future these river basins will have physical scarcity Egypt imports > 50% of its food because of physical scarcity Australia; diversion ¼ of all water away from Murray Darling Basin for agriculture Aral Sea faces environmental catastrophe, although recent attempts to reduce impacts of river diversions for especially cotton production R Ganges: physical stress from pollution and over abstraction Severe water scarcity N China, leading to South North transfer scheme-see later slide Ogallala aquifer provides 1/3 all US irrigation water, but is seriously depleted: the water table is dropping by about 1m/yr. As a fossil reserve, formed probably from past glacial meltwater flows, it is effectively a finite resource Much of sub Saharan Africa suffers from economic scarcity from especially poverty but also lack of infrastructural development. Some 1 bn people involved1
DIFFERENT USERS? Conflicting demands Water conflicts SUPPLY? Diminishing DEMANDS? Rising International conflicts i.e. basin crosses national boundaries Internal conflicts ie within a country Conservation versus exploitation PRESSURE POINT- ie need for management. This is shown spatially as a hotspot of conflict, see map on next slide. Pressure and hence tension and conflict may be over surface flow and/or groundwater supplies Dams and diversions and loss of wetlands are particularly contested. Population growth Consumer demand Industrial growth Agricultural demand Reductions because of: Users abstracting/polluting upstream Deteriorating quality Impact of climate change
Present and potential water conflict hotspots As water supply decreases, tensions will increase as different players try to access common water supplies Many conflicts are transboundary in nature, either between states or countries Insert Figure 2.11 page 47 River basins currently in dispute River basins at risk in the future Large International drainage basins Zambezi Orange Okavango La Plata Mekong Ganges Ob Lake Chad Nile hotly disputed between Ethiopia and Sudan,who control its headwaters, and Egypt. Tigris-Euphrates Iraq + Syria concerns that Turkeys GAP project will divert their water The Aral Sea, an inland drainage basin, once the worlds 4 th largest inland lake has shrunk sine the 1950s after the 2 rivers feeding it: the Amu Dayra and Syr Darya were diverted for irrigation. By 2007 the sea was 10% of original volume and split into 2 lakes. The ex soviet states are in conflict: Uzbekistan, Turkmenistan and Kazakstan. Colorado: disputes between the 7 US states and Mexico it flows through. The river is so overused, that it no longer reaches the sea!. 90% abstracted before reaches Mexico Note: although there have been rising tensions globally, many areas demonstrate effective management to diffuse the situation and create more equitable and sustainable demand-supply balance, such as the Mekong River Committee,& the Nile River Initiative
Colorado river basin: Geographical location Name the states who share the River basin
During the past 50 years this once free flowing river has been tamed by a gigantic plumbing system consisting of 14 major dams and reservoirs. hundreds of smaller dams. a network of aqueducts and canals that supply water to farmers, ranchers and cities.
Today, this domesticated river provides….. electricity (from hydroelectric plants at major dams) water for more than 25 million people in 7 states water used to produce about 15% of the nation's produce and livestock multi-billion recreation industry of – whitewater rafting – boating – fishing – camping – hiking enjoyed by 15 million people a year.
Why is it like this?
Why is there conflict over the water resources? Why would these people all have different views ?
Glen Canyon and Lake Powell
Take away this tamed river and….. Las Vegas, Nevada would be a mostly uninhabited desert area. San Diego, California (which gets 70% of its water from the Colorado), could not support its present population. California's Imperial Valley (which grows a major portion of the nation's vegetables would consist mostly of cactus and mesquite plants.
Three major problems are associated with use of this river's water: the Colorado River basin includes some of the driest lands in the US. Legal pacts in 1922 and 1944 allocate more water to the states in the river's upper basin (Wyoming, Utah, Colorado and New Mexico) and lower basin (Arizona, Nevada and California) and to Mexico, than now flows through the river, even in years without a drought. because of so many withdrawals, the river rarely makes it to the Gulf of California.
Colorado River drought The south-western US is suffering its eighth consecutive year of drought. There are concerns that the Colorado River, which has sustained life in the area for thousands of years, can no longer meet the needs of the tens of millions of people living in major cities such as Las Vegas and Los Angeles. stm
Colorado River case study….. 1.Where is the case study located 2.Why is there an issue? (who are the different users?/ what do they want water for?) 3.What was done about it? 4. When did this happen? 5. Who has benefited?