Global Water Crisis: Too Little, Too Much, or Lack of a Plan?
For most of history, thirsty humans made do with what moisture fell from above: The sun warmed the salty seas, pure water evaporated into the air and then cooled and fell to the earth as precipitation. There it clung to glaciers, froze and thawed in lakes, was absorbed by plant roots, coursed through fractured bedrock, and seeped slowly through soil, into aquifers. Most of it returned to sea and sky all over again. There is as much of that water on the planet today as when the first amphibian flopped ashore; as much as when the ancient Greeks divined the future in the babble of brooks.
From space, the idea of a global water crisis may seem perplexing: 75 percent of the planet’s surface is blue. But usable fresh water is a tiny fraction of what we see - only 2.5 percent of the water on Earth. And two-thirds of that fresh water is locked away in glaciers, icecaps, and permanent snow. Of the stock of accessible fresh water, 99 percent is in underground aquifers - some are nonrenewable; and in some that are replenishable, ground water is slurped up faster by a growing population than it can be replaced.
But even so, say experts, the problem is perhaps more an issue of recognizing water’s true value, using it efficiently and planning for the lean times, than it is a lack of overall supply.
The ongoing historic American drought, with its cascade effect on food and utility prices at home and food costs abroad, is an example of scarcity’s effect.
But superstorm Sandy’s deluge and flooding, says Geoff Dabelko, an environmental expert at Ohio University in Athens, is an example of how the term “global water crisis” can be misleading. It tends to imply that there’s just one kind of crisis - a water shortage.
“The kind of dead-cow-carcass-in-the-desert image that global ‘water crisis’ evokes is very real for some people,” Professor Dabelko says. “But there are so many dimensions.” Too much water - whether from flooding, sea level rise, or more extreme storms - can be just as deadly as too little.
While the balance between water supplies and the demands of a burgeoning population are further complicated by the effect of climate change on delicate hydrological margins, there are those who say there is enough water, if nations learn to plan for a different future - one in which past abundance is no guide.