Physical water scarcity occurs when and where there is not enough water to meet both human demands and those of ecosystems to function effectively. Arid regions frequently suffer from physical water scarcity. It also occurs where water seems abundant but resources are over-committed. This can happen where there is overdevelopment of hydraulic infrastructure, often for irrigation or energy generation. Symptoms of physical water scarcity are severe environmental degradation, declining groundwater and water allocations that favour some groups over others. The term was first defined in a wide-ranging 2007 study on the use of water in agriculture over the previous 50 years. The study was undertaken by a broad partnership of practitioners, researchers and policymakers, overseen by the International Water Management Institute in Sri Lanka, with the aim of finding out if the world has sufficient water resources to produce food for future populations. The study found that more than 1.2 billion people live in areas of physical water scarcity. The term economic water scarcity was used by the study to define situations where demand for water is not satisfied because of a lack of investment in water or a lack of human capacity to satisfy demand. The clean water crisis is a global crisis which is directly related to physical water scarcity. Many third-world countriesaround the world suffer from the clean water crisis due to the physical scarcity of water.
The clean water crisis is an emerging global crisis that affects approximately 785 million people around the world. The lack of clean water is the root of the cause of physical water scarcity. Although clean freshwater is a vital resource for human life, 1.1 billion people lack access to water and 2.7 billion experience water scarcity at least one month in a year. By 2025, it is expected that two-thirds of the world’s population may be facing physical water scarcity. As water becomes scarce, people can’t get enough to drink, wash, or feed crops. As a result economic decline occurs. Due to lack of basic water and sanitation, $260 billion is lost globally each year. Water collectors, mainly women and girls, spend most of the hours of their day collecting water limiting them from being able to receive an education and eventually become part of the workforce. 2.4 billion people suffer from the contamination of water and poor sanitation. Contamination of water can lead to deadly diarrheal diseases such as cholera and typhoid fever, and other water-borne illnesses causing 80% of illnesses around the world. A child dies from a water-related disease every two minutes supporting the fact that one in every four deaths in children under the age of five due to water contaminated diseases. In the year 1900, 2% of the world's population suffered from chronic water shortage. This percentage rapidly increased by 2005 where 35% of the world's population lived in regions with physical water scarcity. As a result, the water crisis is the #4 global risk in terms of its impact on society worldwide.
