There are physical causes and human causes of water insecurity

Water supply → The amount of accessible freshwater, from precipitation and surface and ground stores

Water demand → The amount needed by people for consumption or activities such as farming & industry

Water stress → Where annual water resources are only between 1000 and 1700 m3 per person. There will be supply restrictions & tensions

Water scarcity → Where annual water resources are only between 500 and 1000 m3 per person. People will go without water and there will be conflict and overuse of reserves

• Physical scarcity → When more than 75% of a country's or region's blue water flows are being used
• Economic scarcity → When the development of blue water sources is limited by the lack of capital, technology & good governance Water insecurity → When people do not have enough quality water to sustain livelihoods, human wellbeing and socio-economic development

Physical Factors That Reduce Water Availability

• Greater rates of EVT possibly linked to climate change
• Variations in precipitation rates
• Geology also determines the distribution of aquifers
• Topography - higher relief promotes more precipitation
• Salt water encroachment into groundwater supplies, and salinisation of wells and boreholes ⇒ Diminishing supplies
• Water supplies are spread very unevenly across the world (60% of the world's water supplies are contained in just 10 countries)

Human Factors That Reduce Water Availability

• Contamination of surface and groundwater supplies by domestic, industrial and agricultural activities
• Over-abstraction of water from rivers and groundwater aquifers
• Population growth
• Rising standards of living - people adopt dairy and meat-rich diets which leads to a higher consumption of water
• Economic growth ↑ demand in agriculture, industrial etc settings

The Water Availability Gap

• Growing gap between availability of water in developing and developed countries
• Imbalance of usage (richer countries using up to 10x more water per head)
• Many countries also experience water stress

KEY CONCEPT: The Water Poverty Index

An assessment of the degree of water shortage and the subsequent water insecurity problems

The 5 Parameters

1. Resources: The quantity of surface and groundwater per person and its quality
2. Access: The time and distance involves in obtaining sufficient safer water
3. Capacity: How well the community manages its water
4. Use: How economically water is used in the home and by agriculture and industry
5. Environment: Ecological sustainability (green water)