Fresh water is a limited and finite resource: the uneven distribution of fresh water has long been a source of concern...
While projections are not predictions, these figures point to the need for urgent attention to issues of stabilising population growth and using water resources sustainably...
- globally, the annual population increase of nearly 80 million per year implies an increased demand for freshwater of about 64 billion cubic metres a year - an amount equivalent to the entire annual flow rate of the Rhine River;
- according to United Nations agencies, 1/3 of the world’s population live in countries that are experiencing moderate to high water stress. A country is said to experience water stress when annual water supplies drop below 1,700 cubic metres per person. When supplies drop below 1,000 cubic metres per person per year, the country faces water scarcity for all or part of the year; (1)
- currently, 54% of accessible runoff is appropriated by humans. By the year 2025, 2/3 of the world’s population could be facing serious problems with water availability. Predictions regarding freshwater biodiversity impacts over that time-frame are also quite scaring. A substantial portion of the total freshwater supply is needed to sustain marshes, rivers, coastal wetlands, and the millions of species they shelter. As humanity withdraws a growing share of all available freshwater, less is available to maintain vital wetland ecosystems. Already, over 20% of the approximately 10,000 freshwater fish species in the world are either endangered, threatened or going extinct;
- the world's 6.3 billion people are already appropriating just over half of all the accessible freshwater contained in rivers, lakes, and underground aquifers. By 2025 humankind's share will be at least 70% - a conservative estimate that reflects the impact of population growth alone. If per capita consumption of water resources continues to rise at its current rate, humankind could be using over 90% of all available freshwater by 2025;
- nowadays, between 12.5 and 14 billion cubic metres of water are globally available for human use on an annual basis. In 1989, this amount equaled about 9,000 cubic metres per person per year and by 2000 had dropped to around 7,800 cubic metres per person. In 2025 the amount of water per capita is expected to fall to 5,100 cubic metres per person as the world's population grows from 6 billion to over 8 billion;
- Population Action International (PAI) calculated water stress and scarcity in 1995, with an update in 1997 and projections for 2025 and 2050. The results are startling: in 1995, PAI estimated that 31 countries, home to nearly 1/2 billion people, regularly faced either water stress or water scarcity. In 2025, 48 countries containing about 3 billion people will face water shortages. By 2050 the figures will be 54 countries containing 4 billion people, or 40% of the projected world population of 9.4 billion;
- the fact that the UN's latest median projection for world population in 2050, is lower, at around 8.9 billion does not significantly alter this scenario. The Pilot Analysis of Global Ecosystems (PAGE), carried out by the World Resources Institute, calculated water availability and population pressures by river basin. Their analysis is even more sobering. This approach indicates that currently 2.3 billion people, or 41% of the world’s population, live in water stressed areas. Of this total, 1.7 billion live in water scarce areas, with less than 1,000 cubic meters per person per year. According to the PAGE analysis, by 2025, the number of people suffering from water stress or scarcity could swell to 3.5 billion people, or 48% of the world’s projected population. Moreover, 2.4 billion of them are expected to live in water scarce regions.
- projected urban population growth, especially in Africa and Asia, suggests that urban services will face great challenges over the coming decades to meet fast-growing needs. At the same time, rural areas also face the daunting task of meeting the existing large service gap;
- the 20 countries of the Near East and North Africa face the worst prospects. In fact, the Near East ‘ran out of water’ in 1972 in the sense that, since then, the region has withdrawn more water from its rivers and aquifers every year than is being replenished. Currently, for example, Jordan and Yemen withdraw 30% more water from groundwater supplies every year than is replenished, and Israel's annual water use exceeds the renewable supply by 15%. Inevitably, this means that water tables are falling and aquifers are slowly being sucked dry; (2)
- Africa will face increased population growth over the coming decades, with the greatest increase coming in urban areas. As a result, according to the “Global Water Supply and Sanitation Assessment 2000 Report” carried out by WHO and UNICEF, approximately 210 million people in urban areas will need to be provided with access to water supply services, and 211 million people with sanitation services, if the international coverage targets for 2015 are to be met. A similar number of people in rural areas will also need to gain access;
- currently, some 206 million Africans live in water stressed or water scarce countries. By 2025 the number will rise to about 700 million, as population continues to grow rapidly. Of these, roughly 440 million will live in countries with acute water scarcity (less than 1000 cubic metres per person per year);
- in Asia, at present, approximately 1/3 of the population is urban and 2/3 live in rural areas. But this balance is predicted to shift over the coming decades. By the year 2015, the urban population is projected to be 45% of the region's total, and grow to just over 50% of the total Asian population by 2025. This population growth will place enormous strain on already over-burdened services, especially in urban centres. According to the Assessment 2000, to meet the international development target of halving the proportion of people without access to improved services by 2015, an additional 1.5 billion people in Asia will need access to sanitation facilities, while an additional 980 million will need access to water supply.
(1) These concepts were developed by Swedish hydrologist Malin Falkenmark to gauge current and future water needs and to measure scarcity.
(2) It is a measure of the crisis, that in the early months of 2004 Israel signed a deal with Turkey to ship 50 million cubic metres of water a year, for 20 years, from the river Manavgat in Anatolia, in return for arms.