Lesson objectives: To be able to describe global access to water To be able to explain why water demand is increasing Key terms SupplyDemandUrbanisationExtraction Water deficit Water surplus What is the link between all of the information? Write down 4 statistical facts from p of these facts must be from fig 1.23
Physical water scarcity - where there is not enough water to meet all demands Economic water scarcity – where there is water available but not enough capacity or infrastructure to make use of it
Increasing demand for water in China China’s urban population has grown from 19% in 1979 to 51% in 2012 China’s urban population has grown from 19% in 1979 to 51% in 2012 according to predictions, nearly 70% of the population will live in urban areas by 2030 according to predictions, nearly 70% of the population will live in urban areas by 2030 How and why might this influence water demand in China?
Why is water demand rising in China? Industry uses Agricultural uses (farming) Domestic uses Energy Water management (responses) Impacts on the environment :
Increased water demand in China What? (give details of water consumption increases) Where? Why?
Growing Demand & Industrialisation The growing demand for water is underpinned by China’s continued industrialization with per annum GDP growth of 9 to 10%. Urban China and industry consume 180 billion cubic metres of water per year or over 20 per cent of the total Industry in China uses 3 to 10 times more water, depending on the product, than industries in developed nations. 40,000 gallons of water to manufacture a car and 60,000 gallons to manufacture 1 ton of steel; presumably, the water requirements for such processes are even higher in China.
Agriculture As global food prices soar, policies to encourage grain self-sufficiency will stimulate more grain agriculture, a very water-intensive practice. Increasing proportions of meat in Chinese diets will add additional strains on water. Twenty-five years from now, about half of China's water supply will be used for irrigation to feed its growing population 260 gallons of water are needed to produce 2.2 pounds of wheat and 3,380 gallons of water are needed to produce 2.2 pounds of beef.
Biofuels The production of biofuels has also increased sharply in recent years, which needs for large quantities of water and fertilizers to grow the crops. The production of ethanol, 77 billion litres in 2008, tripled between 2000 and 2007, and is expected to reach 127 billion litres by 2017.
Energy Demands As China’s energy demands soar, with industrialisation & improving standards of living. There will need to be the construction of new coal, and soon nuclear plants, both of which require large sources of water.
Pollution The concentration of heavy industry along water sources means that at least 70% of China’s rivers and lakes are polluted and half of China’s cities have contaminated groundwater. In the north the Yellow river has been so over-exploited that it fails to reach the ocean for most of the year. Further south the Huaihe, considered the country's most polluted river, is frequently linked to the declining health of local residents. Even the Yangtze, which supplies water to a 12th of the world's population, is showing the growing pressure of dams, river traffic and effluent from supercities such as Chongqing, which has a municipal population of 30 million. Less than a third of the waste from China's cities is treated.
Climate Change Global warming may intensify and accelerate global hydrological cycle, which will increase rates of evaporation and precipitation. By 2020, between 75 million to 250 million people may experience increased water stress due to climate change. Glacial runoff supplies the region with about one quarter of its water. As glaciers retreat, this will actually increase water supplies initially (until perhaps 2020, according to the original article), but then water supplies will become even more scarce than they are already. glaciers retreatglaciers retreat
Effects on Ecosystems Among 514 rivers the survey monitored, 60 ran dry in 2000 with their function either degraded or lost. Water volume in the nation's lakes has also dipped 14 per cent with many wetlands shrinking drastically in size, the survey showed.
Demographic mismatch First, China has about 20% of the world’s population, but only 7% of its water resources to sustain it. Second, there is a stark regional north-south imbalance. Only 14.7% of the country’s water is distributed in the vast areas to the north of the Yangtze River, where the amount of arable land accounts for 59.2% of the national total, and the population makes up 44.4% of the total
The World Water Report The World Water report continues by singling out China as a country in danger of water stress because of its inefficient water use and large projects such as the Three Gorges Dam scheme. "Chinese Rivers and lakes are dead and dying, groundwater aquifers are overpumped, uncounted species of aquatic life have been driven to extinction, and direct adverse impacts on both human and ecosystem health are widespread and growing,"
Management Water authorities of Shenzhen are planning to use seawater to meet rising demand. The city will launch a number of seawater desalination projects in power plants and tourism resorts along the east coast during the next five years. So far this year, more than 30 Chinese cities, including Beijing, Shanghai and Guangzhou, have announced plans to increase prices for household water supplies by a range of 0.4 yuan ($0.06) to 1 yuan ($0.15) per cubic meter. The local governments have been pushing up prices, with a view of encouraging more recycling and efficient water use.
Management 2 The lower reaches of the Yellow river, which feeds China's most important farming region, ran dry for 226 days in Between 1991 and 1996, the water table beneath the north China plain fell by an average of 1.5 metres a year. To combat this, work has begun on China's biggest ever construction project - a massive scheme to channel billions of cubic metres of water from the Yangtze to the replenish the dwindling Yellow river.