Water Shortages (Cambridge (CIE) IGCSE Geography): Revision Note

Water Shortages and Management

Water shortages (deficit)

• Many areas of the world have water shortages (deficits)

• Water deficit can be due to:

  • Low supply:

    • Lack of precipitation

    • High levels of evaporation

    • Poor water management

    • Drought

    • Pollution

  • High demand:

    • Increasing population

    • Industry

    • Agriculture

  • A combination of low supply and high demand

• Areas with the greatest water-deficit include:

  • Australia

  • North, East and South Africa

  • Middle East

  • Southwest USA

  • East Brazil, parts of Argentina and Chile

  • India

• These tend to be areas around the Tropic of Cancer and Tropic of Capricorn

• There are different levels of water shortage:

  • Water stress occurs when the supply of water is below 1700 m³ a year per person

  • Water scarcity is when the supply is below 1000 m³ a year per person

• There are two types of water scarcity:

  • Physical water scarcity—when physical access to water is limited due to the climate conditions of the area

  • Economic water scarcity—when a population does not have the money to utilise the available water resources

• The UN Millennium Development Goals (MDG) included Goal 7

• This goal was not met but access to clean water has improved

• In 2020, 74% of the world's population now have access to clean water supplies

• In some areas, there may be water supply, but this is not potable

  • UNICEF estimates 2.2 billion people do not have access to potable (clean drinking) water

  • Around 4.2 billion people do not have access to safely managed sanitation services

• Water scarcity is expected to increase across the world due to:

  • increasing population 

  • development increasing demand

  • climate change increasing aridity

  • pollution

Causes of water shortage

• Many of these areas have a deficit due to low precipitation throughout the year or drought 

• Demand is greater than supply in some countries due to increasing population, industry and agriculture

• In some areas, rivers flow through many countries

  • This leads to issues with water abstraction and other activities

  • The upstream country may:

    • take large amounts of water from the river for agriculture, industry or domestic use, leaving less for the country further downstream

    • build dams or alter river flow, which impacts discharge downstream

    • reduce water quality by introducing pollution to the river

• Higher temperatures may lead to increased evaporation and transpiration, reducing the amount of water available

• The type of land use

  • Agriculture leads to increased water consumption

• In some countries, there is a disparity in water supply between areas

  • China has severe water shortages in the north but water is more available in the south

• Conflict

  • Many of the LEDCs who have struggled to meet the MDG are experiencing conflict 

Impacts of water shortage

• There are many impacts of water shortages, including:

  • Death and illness due to waterborne diseases such as cholera and dysentery

  • Potential for conflicts over water supply, particularly where countries share a river basin

  • Children in rural areas in LEDCs often miss out on school as they are responsible for collecting water (they may have to walk miles to the nearest water source)

  • Lack of food due to:

    • Crops cannot be irrigated so yields are lower

    • Livestock dies due to lack of water

  • Damaged ecosystems and loss of habitats

  • Delayed economic development because water is not available for industry

Managing water supply

• There are many ways in which water supply can be managed but this is easier in MEDCs, where the money to implement these schemes is available

Industry

• Most water in MEDCs is used for industry

• Some of this water could be recycled and used again within the process to reduce consumption

Agriculture

• Drip irrigation, which delivers water to the roots of plants

• Irrigation leads to 40% of the water used being lost to evaporation and poor management

• Drip irrigation reduces this loss significantly

Domestic

• Water-efficient appliances

• Rainwater collection

• Use of grey water for washing cars and watering plants

• Low-flush toilets and water-saving shower heads

• Water companies fixing leaks and improving efficiency

• In LEDCs, water management is more difficult due to a lack of funding

• The involvement of non-governmental organisations (NGOs), such as Water Aid, helps to fund projects

• Appropriate technology is essential to manage water in LEDCs; they include:

  • wells 

  • gravity-fed systems where water is piped from a spring or river higher up a valley

  • boreholes use a hand pump to bring water to the surface

  • rainwater collection from roofs

  • drip irrigation

  • drought-resistant crops

Case Study: Spain

• The average precipitation in southeast Spain is approximately 365 mm a year

• Most precipitation occurs in winter

• The area is one of the driest in Europe

• Agriculture uses 80% of the water available

  • 147,000 hectares of land require irrigation

• Regular droughts mean the supply of water is further reduced

• There is a water deficit as demand exceeds supply

• Tourism increases the problem because:

  • Water parks and golf courses use significant quantities of water 

  • An average tourist uses between 450 and 800 litres per day

  • An average Spaniard uses 127 litres per day

Tagus-Segura Project

• Completed in 1978

• Over 60% of the water flowing into the Tagus is transferred

• A 286 km pipeline that connects four Spanish river basins: Tagus, Jucar, Segura and Guadiana

• The aim was to supply Alicante, Murcia and Cartagena in the southeast to reduce the water deficit

Issues

• Much of the water transferred went to the tourist and leisure users, not to small-scale farmers

• Water consumption in the southeast increased due to an increase in supply

• It is estimated that 15% of the transferred water is being illegally used by leisure users such as golf courses

• Large commercial farms are benefitting more than small-scale farmers

Ebro project

• A second water transfer project was proposed in 2001 to transfer water from the River Ebro

• This project was abandoned due to the

  • failure and issues with the Tagus-Segura project

  • cost

  • threat to the Ebro Delta, as the scheme would have disrupted sediment flow to the delta

• Spain has now moved to utilising desalination plants to meet the demand for water