Water technology

Technology can help increase both water supply and access.
Water transfer is now commonplace as civil engineering skills and construction technology continue to improve.
The dams and canals of the Colorado Project, once the wonder of the world, are now dwarfed by developments in China and Brazil and on the Indian subcontinent. China’s plans are both spectacular and controversial
China's South-North transfer project
1. The south of China is rich in water resources but the north is not.
2. To redistribute these resources and to even out the availability of water, a gigantic south–north water diversion project was begun in 2003.
3. It is expected to take 50 years to complete and will cost $62 billion.
4. The project involves building three canals which run 1,300 km across the eastern, middle and western parts of China and link the country’s four major rivers: the Yangtze, Yellow, Huai and Han
5. The scale of engineering involved in this scheme is awesome.
6. It will transfer a total of 44.8 billion m3 of water per year.
7. Central government will provide 60% of the cost of the scheme, with the rest coming from local authorities, which, in turn, will charge domestic and industrial users.
8. Water conservation, improved irrigation, pollution treatment and environmental protection are included in the plans.
9. Critics are concerned about the uncertainties and risks associated with the project.
10. These include the likelihood of significant ecological and environ- mental impacts along the waterways, resettlement issues and worsening water quality.
11. The pollution of the Yangtze River is already at alarming levels.
12. Untreated industrial and city wastewater is being mixed unchecked with agricultural runoff containing pesticides and fertilisers.
13. The Huai River is already severely polluted and the water of the Yellow River is undrinkable.
14. Some experts fear an ecological disaster.
Desalinisation
1. The process of desalination (also known as desalinisation) is the removal of excess salt and other minerals from water.
2. It produces freshwater suitable for human consumption or irrigation.
3. For a long time, desalination was a technolog- ical success that failed to deliver in economic and environmental terms.
4. However, as water costs and demand have increased, more countries are turning to desali- nation as part of their future water strategy
5. Many of the countries or states involved are relatively well off, technologically developed and increasingly water stressed.
6. In the middle east, Saudi Arabia, the United Arab Emirates (UAE) and Kuwait use cheap energy to distil freshwater from seawater.
7. In the USA, California and Florida lead the list of states using reverse osmosis membrane technology to filter salt from brackish water and rivers.
8. Recent newcomers to this technology include Spain, China, Australia and Israel.
9. The costs of desalination are difficult to calculate, as subsidies are often involved.
10. Cheaper processing and larger plants make it cheaper but the process uses a lot of energy so rising oil costs are increasing the price.
11. . The water produced is of a high quality, although chemically different (in terms of minerals) from rainwater.
12. Water intake and outflow processes have ecological effects, not least because concentrated brine is a by-product of desalination.

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	Erstellt von Jodie Goodacre vor fast 11 Jahre