Definition
Water scarcity
Water scarcity refers to the limited availability of water to meet the needs of human societies.
- Water scarcity occurs when the demand for freshwater exceeds its availability within a region over a specific period.
- It affects both developed and developing nations, but the causes and severity differ.
- Globally, over 1.2 billion people live in areas of chronic water scarcity, and 450 million in low-income countries suffer severe shortages.
- Water scarcity can be seasonal (linked to dry seasons or droughts) or permanent (due to climate or geographic limitations).
- The problem is expected to worsen with climate change, population growth, and industrial expansion.
Note
Physical scarcity often leads to conflicts over shared water resources, such as rivers that cross national boundaries.
Types of Water Scarcity
1. Physical Water Scarcity
- Occurs when natural water resources are insufficient to meet demand.
- Common in arid or semi-arid regions with low rainfall, high evaporation, and limited groundwater.
- Often worsened by over-extraction, deforestation, and pollution that depletes usable sources.
- Physical scarcity typically arises where water consumption exceeds 60% of available renewable supply.
Example
- The Middle East and North Africa (MENA) region faces extreme physical scarcity.
- Some countries like Jordan and Saudi Arabia have less than 100 cubic meters of freshwater per person per year.
Case study
Physical Water Scarcity - Jordan
- Jordan is among the most water-scarce countries in the world, with less than 100 m³ of water per person annually.
- It has a hot, arid climate and relies on limited sources such as the Jordan and Yarmouk Rivers and underground aquifers.
- Groundwater is being depleted faster than it can recharge, and shared river systems reduce national availability.
- Water is distributed weekly to households; families store water in rooftop tanks.
- Jordan is exploring wastewater recycling and imports to meet growing demand.
- Desalination projects from the Red Sea have been proposed but face high costs and energy constraints.
2. Economic Water Scarcity
- Occurs when water exists, but people lack access due to poor infrastructure, political instability, or financial constraints.
- Typical in low-income countries where investment in water pipelines, reservoirs, and sanitation systems is limited.
- This type of scarcity reflects inequality rather than absolute shortage.
Example
Haiti has abundant rainfall but over 70% of its population lacks direct access to safe water due to poor governance and infrastructure.
Case study
Economic Water Scarcity - Haiti
- Despite abundant rainfall, over 70% of Haitians lack access to safe drinking water.
- The main causes include economic underdevelopment, weak governance, and poor infrastructure.
- Waterborne diseases, such as cholera, have caused repeated public health crises.
- Rural communities rely on unprotected wells and rivers that are often contaminated.
- Decades of political instability and natural disasters (earthquakes, hurricanes) have hindered investment in water systems.
Tip
- Physical scarcity = not enough water available.
- Economic scarcity = enough water exists, but it’s inaccessible or unaffordable.
Factors Influencing Water Scarcity
- Population growth: Increases domestic, agricultural, and industrial demand.
- Climate change: Alters precipitation patterns, intensifies droughts, and melts glaciers that feed rivers.
- Pollution: Industrial waste, agricultural runoff, and sewage reduce usable water quality.
- Urbanization: Expanding cities strain limited supplies and aging infrastructure.
- Affluence and lifestyle: Rising incomes lead to greater water consumption (e.g., lawns, pools, meat-heavy diets).
- Political instability: Conflicts over transboundary rivers and poor governance prevent equitable distribution.
Note
- Water scarcity is rarely caused by a single factor.
- It’s often the result of combined human, climatic, and economic pressures.
Global Pattern of Water Scarcity
- Regions with water surplus include Canada, Russia, and parts of South America.
- Regions with water deficit include North Africa, the Middle East, South Asia, and parts of Australia.
- Within countries, scarcity can vary.
- Coastal areas may have more access than inland or rural regions.
- By 2050, over half the global population is expected to live under moderate to severe water stress.
Example
The Murray-Darling Basin in Australia and the Indus Basin in Pakistan are both under increasing pressure due to overuse and reduced rainfall linked to climate change.
Self review
- Define water scarcity and distinguish between physical and economic scarcity.
- Explain two major causes of physical water scarcity and provide examples.
- Discuss why economic water scarcity persists even in regions with high rainfall.
