Thursday, 20 August 2009

Fog-catching nets offer hope for parched villages

Parched communities around the world are turning to fog-catching nets to harvest hundreds of gallons of water a day.

By Tom Leonard in New York Published: 6:21PM BST 19 Aug 2009

Experts say the devices, which resemble volleyball nets and are made of a porous, agricultural plastic mesh which traps the water droplets in the fog, can be an effective solution to the widespread problems of meagre or unclean supplies.
A single 13ft long by 33ft high net alone can collect 66 gallons of water a day, sufficient for a family's needs. The water, which is pure and does not need to be filtered, runs down into troughs and then via pipes into a holding tank.
FogQuest, a Canadian charity that promotes fog net technology, has been involved in dozens of projects across South America as well as Israel, Nepal, Haiti and even in the deserts of Namibia.
In Peru a string of nets have recently been erected on the slopes above Lima. Rain rarely falls on the Peruvian capital or the surrounding hills where many of its poorest citizens live, forcing the population to get water from Andes glaciers many miles away.
But the glaciers are shrinking, prompting fears of serious water shortages.
As in other parts of the world where unscrupulous water suppliers are squeezing supply, local people in Lima are being forced to pay up to six times the usual price for unclean water brought in by lorry.
However, two German scientists have harnessed the dense fogs that sweeps in from the Pacific every winter and last for eight months a year.
Kai Tiedemann and Anne Lummerich, have also developed a more advanced fog catcher with multiple layers of nettings that can catch a shifting wind.
Robert Schemenauer, FogQuest's executive director, said desert dwellers may have started harvesting fog from trees as long as 2,000 years ago.
"We're getting an awful lot of requests now from all over the world. Last week alone, we had interest from East Timor and Kenya," he said.