By 2025, 1.8 billion people could be living in water-scarce areas desperate enough for mass migrations, and another 3 billion could live in water-stressed areas. Today about 750 million people live below the water-stress threshold of 1,700 cubic meters per person per year and more than 1 billion people do not have access to safe drinking water. Water tables are falling on every continent; 40% of humanity depends on international watersheds; agricultural land is becoming brackish; groundwater aquifers are being polluted; and urbanization is increasing water demands faster than many systems can supply. Water withdrawals from lakes and rivers have doubled in the last 40 years. Agriculture accounts for 70% of human usage of fresh water, which needs even more to feed growing populations. Nature also needs sufficient water to be viable for all life support. Hence, more fresh water is needed—not just distribution agreements. Breakthroughs in desalination, like pressurization of seawater to produce vapor jets, filtration via carbon nanotubes, and reverse osmosis, are needed along with less costly pollution treatment. Seawater agriculture on desert coastlines would reduce freshwater agriculture demand.
We need an integrated global water strategy, plan, and management system to focus knowledge, finances, and political will to address this challenge. It should apply the lessons learned from producing more food with less water via drip irrigation and precision agriculture, rain water collection and irrigation, watershed management, selective introduction of water pricing, and replication of successful community-scale projects around the world. The plan should also help convert degraded or abandoned farmlands to forest or grasslands; invest in household sanitation, reforestation, water storage, and treatment of industrial effluents in multipurpose water schemes; and construct eco-friendly dams, pipelines, and aqueducts to move water from areas of abundance to scarcity. Access to clean water and basic sanitation should become human rights. Water can also be conserved by using animal stem cells to produce meat tissue (without the need to create the animal) and by increasing vegetarianism around the world.
About 80% of diseases in the developing world are water-related. Many are due to poor management of human excreta. About 2.6 billion people lack adequate sanitation. Many major rivers now run dry during part of the year before they reach the ocean. UNICEF and WHO estimate that developing nations need at least $11.3 billion a year to meet low-cost basic levels of service for both drinking water and sanitation by 2015. However, the water sector receives only 5% of development assistance today. If the world can meet the MDG goal for water, total economic benefits will be about $38 billion per year, far greater than the costs.
Unless major political and technological changes occur, future conflicts over trade-offs among agricultural, urban, and ecological uses of water are inevitable. Previously, water-sharing agreements have occurred even among people in conflict and have led to cooperation in other areas.
Challenge 2 will be addressed seriously when the number of people without clean water and those suffering from water-borne diseases diminishes by half and when the percentage of water used in agriculture drops for five years in a row.
North America: Each kilowatt-hour of electricity in the U.S. requires about 25 gallons of water for cooling, making power plants the second largest water consumer in the country, after agriculture. Over the past five years, municipal water rates have increased by an average of 27% in the U.S. and 58% in Canada. Water consumption per capita has been lowered over 20 years, yet 16 million Americans face water rationing. Water could become a class problem; poor people will be the first victims in free market distribution. The EPA found that half of all streams in the U.S. are polluted. Government agricultural water subsidies should be changed to encourage conservation. Innovations are increasing from atmospheric water generation to nanofiltration and packets (sachets) for water purification.
article provided millennium-project.org