There is a one-in-two chance of fully depleting reservoir storage by 2050, says University of Colorado study. From the Ecologist, part of the Guardian Environment Network
The Ecologist, part of the Guardian Environment Network
guardian.co.uk 28 Jul 09;
The lifeblood of the American west, the Coloradoc river, is running dry under current usage, according to a study from the University of Colorado.
Travelling almost 1,500 miles, the river supplies drinking and irrigation water for about 30 million people from Colorado to the Gulf of California.
The study looked at how water supplies would be affected by climate fluctuations and water demand.
Reservoirs low
In 2000 reservoirs fed by the river were at 95 per cent of capacity. In 2009 they had dropped to 59 per cent of capacity.
If climate change results in a 10 per cent reduction in the Colorado River's average stream flows, as some recent studies predict, the chances of fully depleting reservoir storage will exceed 25 per cent by 2057.
If climate change results in a 20 per cent reduction, the chances of fully depleting reservoir storage will exceed 50 per cent by 2057, said the study.
Depleting supplies
'On average, drying caused by climate change would increase the risk of fully depleting reservoir storage by nearly ten times more than the risk we expect from population pressures alone,' said study author Balaji Rajagopalan.
'By mid-century this risk translates into a 50 percent chance in any given year of empty reservoirs, an enormous risk and a huge water management challenge,' he said.
Researchers warned against being 'lulled into a false sense of security' by the current high water capacity of the Colorado River system.
'This study, along with others that predict future flow reductions in the Colorado River Basin, suggests that water managers should begin to re-think current water management practices during the next few years before the more serious effects of climate change appear,' said Rajagopalan.
• This article appeared on the Ecologist, part of the Guardian Environment Network
