Managing water supplies using hard engineering

HideShow resource information
  • Created by: ZoeCouch
  • Created on: 23-01-18 09:17
View mindmap
  • Managing water supplies using hard engineering
    • Dams (example: Three Gorges Dam in China)
      • Outline and Aims
        • The building of a dam across the River Yangtze
        • subsequent creation of reservoir upstream (large store of water)
        • To generate HEP
        • river regulation to improve supply and control flooding on Yangtze
        • build up surplus of water to be diverted to northern china
      • Benefits
        • Electricity generated is vital for China's growth
        • reduced water shortage risk in Bejing due to diversion of surplus water
        • Has reduced water shortage close to the Yangtze improving supply.
        • Dams provide a huge addition to blue water component by storing 15% global runoff- more accessible for China
      • Costs
        • 632km² of land has been flooded to form reservoir
        • 1.3million people have been relocated from 1500 villages and towns
        • Reservoir water quality is low due to industrial, agricultural and sewage waste entering from upstream
        • Decomposing vegetation in the reservoir produces methane, released when water passed through HEP turbines- increasing Greenhouse Gas effect
        • expensive
        • Now Yangtze is navigable for cruise ships and trade ships
      • Effective?
        • The Dam was effective at reducing major downstream flooding from once every 10 years to once every 100 years
        • The dam has increased availability reducing economic water scarcity in sme areas
        • water surplus diversion allows dam to provide not just for local area but for areas further north such as Bejing which have reduced resources.
        • Pollution of water reduces water quality and means there is less good quality water per capita than if other methods such as desalination had been used for management.
    • Desalination (example: Israel)
      • Outline and Aims
        • By piping seawater from the Mediterranean and Red Sea to new inland desalination plants, (five opened in 2013), the aim is to provide 70% of Israels domestic water supply by 2020
      • Costs
        • dumping desalinated water (high in salt concentration) near shoreline will have adverse effects on coral reefs and their food webs
        • the main costs are environmental with major ecological impact on marine life
        • Each plant requires its own power station and adds to C02 emissions though much of energy used is solar
        • produces vast amount of brine which harm ecosystems
      • Benefits
        • less energy intensive and easier to implement on a larger scale
        • produces up to 600 tonnes of potable water per hour
        • sustainable process as it uses saltwater not freshwater, so conserves water for suture generations
        • more recent discoveries in technology are reducing cost of desalination which is far more cost effective than using increasingly expensive freshwater resources
      • Effective?
        • reduces water shortages overall and provides much water for Israel which can then be evenly distributed at a cost effective price.
        • effective management through conservation of freshwater supplies
        • desalination is reliable and predictable
    • North-South Transfer Project in China
      • Outline and Aims
        • Three routes will take water from Yangtze river to northern China: a Western route to the Yellow river, an Eastern route via a series of lakes and a Central route.
        • To reduce risk of water shortages in Bejing and boost economic development.
        • Bejing needs water as despite home to 35% of China's population and with 40% arable land, it recieves only 7% of water
        • due for completion by 2050
      • Benefits
        • reduce abstraction of groundwater
        • reduce water shortages caused by drought in the North
        • Increased food supply from further irrigation in the north
        • reduces physical water scarcity in Bejing
      • Costs
        • It will submerge 370km²  of land
        • May increase water shortage risk in south if too much is drained
        • Yangtze river already polluted and water of yellow river considered undrinkable
        • damage to fish stocks, spreading disease and pollution and well as acting a a pathway to introduce alien species into new river environments
        • potential increase for flood risk
        • East route is industrial and risks further pollution
      • Effective?
        • The transfer project is effective when considering the reduced water shortages in north China and more equal distribution
        • The potential for pollution decreasing availability of good quality water is not effective as a management strategy however
        • The fact that water distribution could potentially sway in the opposite direction with the south recieving less water is not effective management

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Water resources »