Water Cycle Case Studies Flashcards
Singapore- Soft engineering/conservation
high population density, but the countries small size means it has difficulty collecting and storing precipitation
-as a wealthy country it has used several methods to overcome this problem= importing water from neighbouring Malaysia, and recycling water in their NEWater scheme, where grey water is purified and disinfected
-in 2010= 30% made up drinking water
(in the future this will provide 55% of the country’s needs)
Uzbekistan- Rainwater Harvesting (intermediate)
-put farmers in control of their irrigation network
-cut consumption by 30%
Cocacola- Water conservation
-had an intensive use of water
-committed to cleaning all their waste water by 2010
-then recycle some of it as waste water
Aral Sea Restoration- Hard Engineering
-world bank 66million pound rescue project
-aim to reduce amount of water spilling out in to the South Aral Sea
-constructing a 12km long dyke across the North Aral Sea to its neighbour in the south
-finished in summer 2005
-leading to an increase of 3.3m which scientist had calculated would take 10years
-return of the fisheries= social and economically successful
GAP project- Hard Engineering
Project:
-17 hydroelectric power stations
-21 dams
-built across Tigris and Euphrates rivers
-21 dams
-£32 billion (World Bank refused Turkey assistance as would harm the interest of downstream neighbours Syria and Iraq
Impacts:
-Both Syria and Iraq depend greatly on these rivers- Syria almost completely reliant on Euphrates and Iraq suffering from the removal of water from both Syria and Turkey
-largely arid Middle Est= most likely location for first world war (1954 Iraq put troops on Syrian border and threatened to destroy Syrian dam on Euphrates)
-Hasankyef in Batman province will be flooded home to 3800 people and thousands of Kurdish archaeological sites dating back 10,000 years
Three Gorges Dam- Hard Engineering
China
-vital for educing escalating flood damage, water and power shortage which are all important for China’s economic development
-expensive= 24 billion
-transfer of 25 billion m3 of freshwater a year from Yangtze River Basin over 1000km to the north (particularly North East, Beijing which is very water scarce)
- hydropower generated will provide 10% of China’s current needs
-loss of farmland and cultural heritage due to flooding= 300,000 people displaced, over 1000 historical sites submerged
-increases earthquake risk
Nile River Basin- Water Conflict
-waters shared by 11 African countries
-Egypt is the last country that the river flows through- depends on it for 95% of its needs
-Countries upstream have been pushing for amendments that would allow them to build dams
-in 2015 an agreement was reached between Ethiopia, Sudan and Egypt, which enabled Ethiopia to start building the Grand Ethiopia Dam.
-However, there is no modern agreement between all Nile countries, so future conflict is likely
Colorado- Water Conflict
One of the major rivers in the USA
There are several challenges for managing this basin in an integrated way:
-large size of basin and long length of river
-large water demand and growing population
-large parts of basin are semi-arid (as climate change is creating drier conditions)
-7 US states and Mexico take water from the Colorado.
North London Artificial Recharge Scheme- Hard Engineering
-chalk aquifer which is artificially topped up when rainfall is plentiful (surplus)
-confined by a layer of less permeable London clay-makes it less leaky
-chalk rock acts like a big sponge holding water for when we really need it
-used since 1995 during dry spells in 1997,2003,2005 and 2006
-improved output after 2006 drought from 150 million litres a day to 180
-
Water Sustainable Development Goals- Water Quality
-water scarcity affects more than 40% of global population
-more than 800 children die every day and more than 2 million people die a year from diarrhoeal diseases
-World Health Organisation estimates extending basic water and sanitation services to the unserved would cost $28.4 billion
-however economic impact of not investing= 4.3% of Sub Saharan Africa GDP and 6.4% of India’s GDP lost due to impacts
Surpluses: Somerset Levels
Location: Somerset Levels
-dec 2013-feb 2014
-river Parrett and river Tone
-thousands of years ago area was covered by sea= drained to allow for agriculture, villages and wetland conservation
Causes:
-prolonged rainfall=200% higher than average for that month
-caused ground to be saturated
-low lying land= more vulnerable to flooding
-high tides and storm surges from Bristol channel= force floodwater up rivers
-lack of dredging= had not been dredged for 30 years so clogged with sediment (should have been done every 8)
-land use= changing in farming practices- much of the land has been converted from grassland to grow maize so less ale to retain water= increased surface runoff
Impacts:
-65km2 of land=underwater
-600 homes flooded
-6880 hectares of farmland flooded
-hundreds evacuated
-cost tourism industry=200 million
Response:
-65 pumps used to drain 65million m3 of water
-FLAG organised fundraising and provided relief
-in November 2014 completed dredging o rivers costing 6 million
Surpluses- UK Storms
-during the winter of 2015-16 northern parts of the UK were affected by a sequence of low-pressure systems= providing periods of prolonged intense heavy rainfall
-storm Desmond caused flooding in Cumbria with over a month’s rainfall in one day
-Overall, 16,000 properties in England were flooded. The UK government provided 200 million for flood recovery, and estimated total economic costs were 5 billion.
Sahel- Drought
-since 1960s has been a decline in amount of rainfall
-El Nino events have influenced this
-high sea temperatures from global warming prevent moist Atlantic air moving over Western Sahel
-desertification has resulted from overuse of land due to population pressures
California- Drought
-Cooler water temperatures known as La Nina tend to produce drier conditions in the west.
-Environmental= about 1000 more wildfires have occurred, prolonged drought threatens wildlife
-Economic= farmers have adopted more more efficient water management technologies
-Social= water shortages restrictions, competition over water supply for agriculture, domestic use etc could escalate to conflict over water use
-Desalination in California= It increases the amount of water in stressed areas, effective as 97% of the worlds water comes from the sea. DISAD= expensive. However, as the price of freshwater rises, countries will look to the seas for their water supplies.
Water insecurity- Gaza aquifer
Gaza aquifer=permeable band of sandstone underling the coastal plain of Israel and the Gaza Strip
-it is Gaza’s only source of freshwater
-water withdrawals exceed natural recharge rate
-over abstraction has resulted in a fall in the water table so has led to salt water encroachment up to 1.5km inland
-pollution from raw sewage of squatter settlements has degraded 90-95% of Gaza’s water supply
-population growth and climate energy threaten water supplies in an arid region
-long standing conflict between Israelis and Palestinians makes sharing water very difficult
-today less than 10% Gazans have access to safe supply of water
