updated November 2015
A search for the causes of water scarcity points ultimately to political failings in response to self-evident symptoms of unsustainable consumption of a critical natural resource.
A quarter of the world’s rivers fail to complete their natural journey to the sea, including the once mighty Yellow River in China and the Murray-Darling River in Australia. Where rivers do flow, pollution often destroys fish species which once provided protein and livelihoods. Pioneering satellite-based measurement has revealed that 21 out of 37 of the world’s major aquifers are being exploited unsustainably, their levels falling dramatically.
The proportion of global freshwater comsumption attributed to contemporary industry and agriculture has risen to 88%, both sectors now demanding water-intensive and energy-intensive methods of production.
Water is used in great quantities for cooling in thermal and nuclear power generation, as well as in the extraction of coal, oil and gas. And the dynamic expansion of food grain production in Asia over the last 40 years – often described as the “green revolution” – has been achieved through modern farming methods which require high input of water. The globalisation of meat and dairy-based diets further adds to the water dependency of agriculture.
The consequence of these trends has been over-extraction of freshwater and pollution of surface water. Surface waters are polluted by run-off of chemicals used in farming and by untreated industrial and household wastewater in cities. This is an acute problem in less developed countries where environmental and sanitation regulations remain inadequate or unenforced.
Population growth acts as a catalyst on all of these drivers of water scarcity. Most of the world’s population growth will occur in the cities of developing countries, many of which are already logistically overwhelmed by unregulated slum development. Whilst cities were often founded in proximity to good freshwater supplies, the benevolence of nature rarely extends to megacity concentrations of over ten million people.
Despite the environmental distress signals associated with water scarcity, government policies on freshwater have generally bowed to the insatiability of modern lifestyles. Political will is challenged still further by unnerving projections of the drivers that will determine future demand for freshwater.
This rising pressure will be most acute in the energy and food sectors. The World Resources Institute estimates that global food production must rise by 69% between 2006 and 2050.
World primary energy demand will increase by one third between 2011 and 2035, according to the International Energy Agency. Despite the emergence of renewable energy sources, dependence on traditional water-intensive mining and power generation is projected to rise in coming years.
Population growth and rising wealth drive this overall scenario inexorably into crisis territory. World population is projected to grow from 7.3 billion to 9.7 billion by 2050.
The cumulative effect of these demand drivers will lift global demand for freshwater by 53% by 2030, according to the 2030 Water Resources Group, a consortium of private sector interests supported by the World Bank. USAID has warned that “by 2025, two-thirds of the world’s population could be living in severe water stress conditions.”
Water in the Anthropocene charts the impact of humanity on the global water cycle
from International Geosphere-Biosphere Programme
Upstream farmers extract and pollute water causing water scarcity for downstream pastoralists in Kenya’s Kimana Wetlands
from Wetlands International
more Water Scarcity briefings
Water Energy Food Nexus
Causes of Water Scarcity
Climate Change and Water Scarcity
Solutions to Water Scarcity
Water Governance and Sustainable Development Goal
Access to Drinking Water
Source material and useful links