The fouling of the waterways and surrounding river basins contributed to the total of 25 million environmental refugees last year, for the first time exceeding the world's 21 million war-related refugees, said the World Commission on Water for the 21st Century.
The findings are part of a report the commission expects to complete at a two-day meeting underway at The Hague, Netherlands. The panel, backed by the World Bank and United Nations agencies on children, development, the environment and other issues, has been charged with finding a way to ensure there is enough water for the world's growing population in the next century.
"We have to pay attention to how the world manages its water," said Arienne Naber, a geologist who is a commission consultant.
"Production has to be increased, quality improved ... to guarantee that we can meet the water needs of all the people on earth and protect the environment," she said in an interview.
The commission gathered information on the river portion of the study from specialists around the world and an analysis of existing material.
It concluded that of the 500 major rivers in the world, the Amazon in South America and the Congo in sub-Saharan Africa are the healthiest. Both have few industrial centers near their banks, the report noted.
By contrast, overuse and misuse of land and water resources in river basins elsewhere has "seriously depleted and polluted" them, the commission said. That, it said, is "degrading and poisoning" the rivers' surrounding ecosystems, "threatening the health and livelihoods of people who depend upon them for irrigation, drinking and industrial water."
The main reason is lack of coordinated management of watersheds, which often cross national boundaries or as in the case of the Colorado River in the United States several state boundaries.
"All the success stories show that cooperation leads you everywhere," Naber said. The commission will recommend comprehensive regional planning among a long list of other remedies aimed at increasing water production while saving the environment, she said.
The final commission report and an action plan is to be presented for consideration to a world forum of government ministers and others, in March in The Hague.
Among other findings in the report:
- The Yellow River in China's most important agricultural region is severely polluted and ran dry in its lower reaches 226 days out of the year in 1997. Health problems are growing because of poor water quality.
- Au Darya's and Syr Darya's flow into the Aral Sea in Central Asia has been reduced by three-quarters and has caused a catastrophic regression in sea levels, 53 feet between 1962 and 1994. The region suffers the highest rate of infant mortality of all regions of the former Soviet Union because poor water flow and fertilizer runoff have fouled the seabed.
- The Colorado River in the United States, irrigating more than 3.7 million acres of farmland, is so exploited and polluted by agriculture that little is left to protect the ecosystem downstream, which has turned from lush green to salty and desolate marshes.
- More than 90 percent of the natural flow of the Nile River in Africa, the longest waterway in the world, is used for irrigation or is lost through evaporation, primarily from reservoirs. What reaches the Mediterranean Sea is heavily polluted with irrigation drainage and industrial and municipal waste.