21世纪的食用水安全问题

In the 21st century, water scarcity is one of the greatest challenges to human development, and in some cases, even survival.

Over 40 percent of the world’s population, some 2.8 billion people, live in regions impacted by water scarcity. Close to half of them live in areas where demand for water exceeds the available supply.

Lack of access to water has a number of obvious consequences, such as low agricultural productivity, and increased incidence of illness due to reliance on poor quality sources in limited supply. But its impact goes far beyond the obvious. Because 70 percent of water is used for food production, water scarcity contributes to, for example, higher food prices, environmental degradation, and dampening of economic growth in the regions most affected.

And the news gets worse—global water demand is projected to increase by 55 percent in the first half of this century, further increasing competition for resources among domestic, agricultural and other users.

That is why the U.S. Agency for International Development, or USAID, and Sweden’s Development Agency, SIDA, launched, in early September: Securing Water for Food: A Grand Challenge for Development. The $25 million initiative will help fund and accelerate scientific and technological innovations that can aid developing and emerging countries to more effectively use and manage the water required to produce food.

The program will focus on three areas critical to reducing water scarcity in the food value chain: improving water efficiency and reusing waste water; improving and building effective rainwater capture and storage systems in areas where water availability is seasonally variable, thus securing water supplies throughout the year and building resiliency to drought; and finally, improving water quality, specifically saline content, in coastal areas, where a combination of over-pumping for irrigation and rising sea-levels are causing salt water to leach into freshwater aquifers, forcing farmers to use poor quality water and diminishing farm productivity.

“Water scarcity and its impact on food security affects everyone on the planet,” said USAID Administrator, Dr. Rajiv Shah. “By harnessing the expertise and creativity of the world's brightest innovators, we can tackle this critical challenge with new thinking and partnerships.”