GCSE Geography - The Challenge of Resource Management: Part 2 - Water

water surplus

water supply exceeds demand

water deficit

demand for water exceeds supply

water insecurity

insufficient water availability to ensure population lives comfortably

percentage of water on Earth that is freshwater

2\.5%

percentage of water on Earth that is unusable (locked up in ice sheets and glaciers)

79%

freshwater uses

* domestic (6%)
* agricultural (69%)
* industrial (20%)
* energy
* leisure

global distribution of water scarcity

countries 30° north and south of the equator

reasons for increasing water consumption

* increased domestic demand
* increased agricultural demand
* progression of sanitation
* increased industrial production
* population growth

factors affecting water availability

* climate
* geology
* over-abstraction
* pollution
* limited infrastructure
* poverty

effect of climate on water availability

* decreasing rainfall feeding lakes and rivers for water supply leads to low water availability
* rising temperatures lead to evaporation so low water availability

effect of geology on water availability

* rainfall flows down to rocks beneath the ground
* some rocks are permeable and allow water to flow through them which leads to less surface water
* permeable rocks form aquifers which mean they are stores of water

effect of over-abstraction on water availability

when water is taken from aquifers, groundwater levels fall

over-abstraction

amount of water taken exceeds amount of water falling as rain

effect of pollution on water availability

* makes drinking water unsafe
* untreated sewage and waste water from factories cause issues
* pollutants can infiltrate into groundwater

effect of limited infrastructure on water availability

* pipelines required to safely move water from place to place
* sealed pipes reduce potential for leaks and pollution

effect of poverty on water availability

* nearly 1 billion people in Africa do not have access to safe, clean water
* if you cannot afford to pay for water, you are forced to use alternative sources which may not be safe
* locks into a cycle of poverty (unable to afford of water → ill → unable to work and earn money)

impacts of water insecurity

no access to sanitation in LICs and NEEs, impact on agriculture and food production, health risks in squatter settlements with open sewers, breeding of insects in stagnant water, impact on industry, water conflict

2 main reasons for increasing water consumption

* rising population
* economic development

spatial scale

area impacted

temporal scale

time that something is affected for

impacts of water insecurity on lives

* conflict
* disease
* queuing at standpipes

example of water conflict

conflict between Turkey, Iraq and Syria as Turkish dams restrict water flow to Iraq and Syria

strategies to increase water supply

* dams and reservoirs
* water transfer and storage
* desalination plants

explain how dams and reservoirs work

dams block rivers so that reservoirs of water build up behind

advantages of dams and reservoirs

* reliable
* supply all year round

disadvantages of dams and reservoirs

* ecosystems destroyed by flooding
* homes lost where valleys are drowned
* expensive
* potential for large losses of water

explain how water transfer and storage works

transfer of water from areas of surplus to areas of deficit via canals and pipelines

advantages of water transfer and storage

* evens uneven water distribution
* relieves water shortages
* supplies major cities

disadvantages of water transfer and storage

* expensive
* often encourage unsustainable and wasteful water usage in receiving region
* environmental impacts in supplier region (eg. increased pollution)

explain how desalination works

removal of salt and other minerals from seawater by heating and evaporation or passing through special membranes

advantages of desalination

* widens variety of water suppliers
* produces more freshwater safe for humans

disadvantages of desalination

* expensive
* over exhausting resources

example of large scale water transfer scheme

Indira Gandhi Canal

advantages of the Indira Gandhi Canal

* irrigates 500,000 hectares of land- has turned previously infertile desert land into productive agricultural land- this has boosted local economy dramatically
* reduces sandstorms by affecting microclimate of area
* improved sanitation in Rajasthan- water can be used for drinking and domestic purposes

disadvantages of the Indira Gandhi Canal

* increased cancer rates from chemical fertiliser leaks
* salinisation due to excessive water use for irrigation
* land can become waterlogged

Indira Gandhi Canal

* transports Himalayan river water south west through the Punjab region to the Thar Desert in the north west of Rajasthan state
* series of irrigation canals
* built to combat drought and famine in Rajasthan

strategies for sustainable usage of water

* conservation
* groundwater management
* recycling
* grey water

water conservation

using less water (eg. fixing leaking reservoirs, dual flush lavatories, water meters, efficient washing machines and dishwashers)

groundwater management

* monitoring amount of groundwater that is extracted to ensure it is not extracted faster than can be replaced naturally
* laws can be passed to enforce this
* companies that leak industrial waste will be fined
* farmers encouraged to reduce usage of artificial fertilisers and pesticides

recycled water

* reclaimed water
* piped to water treatment plants
* used again for irrigation, industry, drinking

grey water

* type of recycled water
* domestic waste (not including toilets)
* used for irrigating gardens or farmland, washing cars, flushing toilets, not used for drinking
* conserves energy as less needed for treating water

sustainable water usage

* producing as little waste as possible
* ensuring there is enough to meet everyone’s current needs while also ensuring future generations’ needs are met

example of local sustainable water supply scheme

sand dams in Kenya

advantages of sand dams

* wimple, low maintenance, adaptable
* low cost
* local scale
* sustainable to local wildlife/ecosystems
* socially sustainable as it uses locally sourced materials and encourages community cooperation as they are community owned and managed

sand dam

* low reinforced concrete wall built across section of a seasonal river
* traps flood water and sand behind dam
* wet sand contains water which is stored

advanced technology

* luxury, not necessity
* high-tech
* prior knowledge of how technology works
* time, money and research to create
* eg. desalinisation

intermediate technology

* meeting need that it is required for
* simpler to function
* less features
* less time, money and research to create than advanced
* eg. sand dam

appropriate technology

* suitable for situation
* meets a need