Water (AQA GCSE Geography)

• Water is essential for life but only 2.5% of water on Earth is freshwater

Sources of water

• It is used in all aspects of life for domestic use, agriculture, industry and energy
• Global water use by sector is: 
  • 70% agriculture: irrigation of crops and water for livestock
  • 20% industry: producing goods and generating energy
  • 10% domestic: toilets, cooking, cleaning, washing
• The use by sector varies across countries depending on whether they are HIC, NEE or LIC

• Water supplies are not evenly distributed across the globe

Factors affecting supply 

• • Climate: the amount of precipitation, rates of evapotranspiration and changes in climate affects the water available
  • Geology: affects where aquifers and groundwater are located and how much water is stored
  • Rivers: where they flow affects the availability of water
  • Pollution: 80% of waste water is untreated this impacts on the water quality and whether it is safe to use
  • Over-abstraction: reduces the available stores of water
  • Infrastructure: pipes and canals used to transfer water, water treatment works and pumping stations are all expensive and many LICs lack infrastructure particularly in rural areas due to the cost. Even in HICs and NEEs remote and rural areas may not have the infrastructure needed to supply water
  • Poverty: lack of money means that people cannot afford a clean water supply or bottled water

Water security

• To be water secure is to have a clean, reliable source of water 
• A place or country that does not have this is water insecure

Water surplus

• Areas of water surplus (where the supply of water is greater than the demand) may be the result of:
  
  • High supply: high precipitation, low evaporation rates, effective water management
  • Low demand: low population, effective water management, low temperatures
  • A combination of high supply and low demand
  • Areas with a surplus include:
    • North-east Brazil in the Amazon rainforest
    • Canada and parts of north USA
    • Russia

Water deficit

• Areas of water deficit (where the demand for water is greater than the supply) may be the result of:
  
  • Low supply: lack of precipitation, high levels of evaporation, poor water management
  • High demand: increasing population, industry and agriculture
  • A combination of low supply and high demand
  • Areas with the greatest water deficit include:
    • Australia
    • North, East and South Africa
    • Middle East
    • West USA
    • Parts of South America 
    • India

Water surplus and deficit

• There are different levels of water shortage: these are water stress and water scarcity:
  • Water stress occurs when the supply of water is below 1700m³ a year per person
  • Water scarcity is when the supply is below 1000m³ a year per person

Reasons for increasing water consumption

• Water consumption is increasing across the world

Global freshwater use

• Population growth: there are now over 8 billion people 
  • Each person requires about 2 litres of clean drinking water a day to remain in good health
  • In addition 18 litres per person is needed for things like sanitation and cooking
  • As well as an increase in domestic water demand, population growth also increases the use of water for:
    • Energy production
    • Agriculture
    • Industry
• Economic development: as countries develop the demand for water increases because:
  • People have more items which use water such as dishwashers, toilets and showers
  • Industry increases and factories use large quantities of water
  • Intensive agriculture is needed as people eat more food, and irrigation systems use large quantities of water
  • As more people move to urban areas the demand for water for drinking and sanitation increases

• Water insecurity has the greatest impact on LICs and NEEs
• Lack of water treatment, infrastructure and waste disposal means that water supplies are:
  • Polluted by industrial waste: where there are laws about waste disposal these are often not enforced
  • Agricultural pollution due to increasing use of pesticides and fertilisers
  • Domestic waste and sewage often get into the water supply
• Approximately 2.2 billion people lack access to safely managed water and 4.2 million lack safely managed sanitation

Health impacts

• This leads to:
  • Spread of waterborne diseases such as cholera, typhoid fever and dysentery
  • Diarrhoea (one of the most common effects of waterborne disease) which leads to the death of more than 0.5 million children a year
  • Unsafe water leads to 1.2 million deaths a year
  • Fall in income as people are unable to work due to illness

Death Rate per 100,000 people due to unsafe water sources

Agriculture

• In areas of water insecurity irrigation will have to be reduced or may not be possible leading to:
  • A reduction in yields
  • Crop failure
  • Food shortages
  • Food price increases

Industry

• Industries use large quantities of water when this is not available this leads to:
  • A decrease in production
  • Loss of income for businesses and countries 
  • Interruption of energy supplies as electricity production may also rely on water supplies for cooling or hydroelectric power

Conflict

• At least 60% of the world's water sources: rivers and aquifers: cross a boundary between countries
  • The actions in one country can have significant impacts on countries and regions downstream, including:
    • Over-abstraction
    • Construction of dams and reservoirs
    • Pollution (sewage, industrial and agricultural waste)
  • Mismanagement of water sources can cause conflict between neighbouring countries and regions
• The construction of the dams on the Tigris and Euphrates rivers in Turkey has significantly affected water flow into Syria and Iraq
  • During the filling of the Ilisu Dam in Turkey in 2019 the water flow into Iraq decreased 50%
  • The quality of the water was also affected: in Basra people's health was severely affected with an increase in rashes, diarrhoea and vomiting

• On the border between India and China there have been clashes between communities due to concerns that China was reducing water flow into India

• Increasing demand requires increasing water supply which can be achieved in a range of ways
  • Increased storage and diversion of supplies
  • Dams and reservoirs
  • Desalination
  • Water transfer

Table Showing Advantages and Disadvantages to Strategies to Increase Water Supply

River management in China

• The average precipitation in north-east China is approximately 200-400mm a year
• Most precipitation occurs during the brief wet season
• Average rainfall has steadily decreased since the 1950s
• The main industrial areas and regions of economic growth are on the North China Plain around Tianjin and Beijing
• The main water source for the area has been groundwater:
  • Demand for water in Beijing alone is 3.6 billion cubic meters 
  • Supply of freshwater in Beijing is 3 billion cubic meters
  • There is a significant water deficit
  • The over abstraction of groundwater has led to subsidence in some areas of the city of 11cm

South-north water transfer project

• Aims to transfer 12 trillion gallons of water a year from the south of China to the area around Beijing
• Central section was completed in 2014
• Final completion estimated to be in 2050
• It will link China's four main rivers: Yangtze, Yellow, Huaihe and Haihe

Three Gorges Dam

• Constructed between 1994 and 2012

• Sustainable water supplies:
  • Do not cause harm to the natural environment
  • Benefit local communities
  • Reduce waste
  • Can be used globally

Water Conservation

• Involves reducing waste and using water less
  • Reduce leaks: it is estimated that globally 45 million m³ of water is lost per day through broken pipes and other leaks
  • Education: to inform people why water conservation is important encourage people to use and waste less 
  • Water meters: reduce water use as people pay for the water they use and so tend to waste less
  • Water efficient appliances: shower heads, low flush toilets and water efficient washing machines, dishwashers all use less water
  • Reduce pollution: pollution means that water cannot be used 
  • Efficient irrigation: drip irrigation reduces the amount of water lost through evaporation

Groundwater management

• Groundwater is the water stored underground in aquifers
• These can be affected by:
  • Over abstraction
  • Pollution
• Sustainable management of aquifers includes:
  • Maintaining a balance between water abstraction and recharge (either natural or artificial from rivers and lakes)
  • Monitoring water tables and quality
• In HICs groundwater is usually carefully monitored and managed: although in some areas such as California there is increasing concern that over abstraction is resulting in the aquifers being severely depleted
• In LICs and some NEEs water pollution and over abstraction are common leading to exhaustion of aquifers in areas such as the Sahel in Sub Saharan Africa

Recycling

• Waste water from industry and domestic use which is treated so that it can be reused

Grey water

• Grey water is the term used to describe domestic waste water
• This can be used both inside and outside the home in any situation where drinking water quality is not required, including:
  • Flushing the toilet
  • Watering the garden
  • Cleaning car

Background

• The Shinja resettlement area suffers acute water shortages
• The community only had shallow wells 
• Which dry up a few months at the end of the rainy season
• This led to issues with sanitation and hygiene

Scheme

• Elephant pumps were installed in a number of communities
• The pumps are inexpensive to make and repair
• Made from local materials
• They are enclosed which reduces contamination

Impacts

• Water and sanitation diseases such as diarrhoea and bilharzia decreased
• Vegetable growing and livestock rearing increased
• Reduced the potential for conflict with neighbouring communities
• Time taken to collect water was significantly reduced
• Food intake increased and was of better quality
• Attendance at school increased as children were not involved in water collection