Experts Look to Solve World’s Growing Water Shortage
Experts are franticly searching for a solution to the world’s growing water footprint, as urban populations increase and demand for biofuels cause water problems for farmland.
As many as 2.5 billion people (half the population of Earth) have no access to sanitation – most of them living in urban slums. The world’s cities are booming by 1 million people a week and the aging water systems are being taxed.
"Something needs to change. It needs to change quickly, and it needs to be fairly dramatic," said Carol A. Howe, an expert working for a UNESCO-led water development project called Switch.
"What we are doing now can’t keep up with the issues we already have," said Howe.
Scientists have calculated a carbon footprint – the amount of greenhouse gases produced by human activity – and are now working on a water footprint to manage the amount of water needed to produce various goods and services.
It takes 70-400 times as much water to create energy from biofuels as it does from fossil fuels, according to a report published by UNESCO-IHE, the Institute for Water Education in Delft.
The report says the production of crude oil requires a little more than one cubic meter of water for one unit of energy, compared with 61 cubic meters to grow biomass in Brazil – mostly sugar used for ethanol – for the same amount of energy. And according to the report, the water footprint of biomass grown in the Netherlands is 24 cubic meters.
Experiments are now underway in a dozen cities from Lima to Beijing looking to ease the pressure on water sources.
The Pilot Projects is an ongoing mission by the U.N. Education, Scientific and Cultural Organization that is funded by the European Union in order to attack various issues such as turning rooftops into gardens, capturing and recycling rain, recharging underground water reservoirs with waste water, and swapping traditional flush sanitation for dry toilets.
According to Howe, in Birmingham, England they are monitoring the effects of green roofs to reduce flooding during storms, to cut energy needs and to study how to capture run-off to reduce water needs in the buildings and surrounding areas.
Treated water is being channeled into the aquifer through the natural filtering system of the soil in Tel Aviv, Israel in hopes that the water can be reused for human consumption.
“The United Nations is almost certain to miss its 2015 goal of halving the percentage of the world’s population who lack adequate sanitation. The goal takes 1990 as the base level,” said Gary Amy, a professor of urban water supply and sanitation with UNESCO-IHE.
Amy says accounting for population growth, some 500,000 new people every day would have to be connected to a sanitation system to meet the U.N. target.
“Waterless toilets, using either chemicals or composting, are being tested in Ghana, Kenya, Peru, Egypt and elsewhere. They also enhance the possibility of separating human waste, using liquid waste as a rich source of nutrients for crops,” said Amy.
Amy says that if all the urine in Africa were captured, it could match all the nitrogen and phosphates used for agriculture.
“Standard mechanisms consume about 25 percent of all residential water – drinking water that is literally flushed down the toilet. It takes a lot of energy and money to bring in the water, to treat it, to put into the toilet, to treat it again, and to put it into the river system," said Howe.
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