Fog Harvesting Provides Relief and Economic Gains for Thirsty Peruvian Villages

By Eliot Levine

Kai Tiedemann (front) and local worker Segundo Velasquez inspect a net in April 2007 that Tiedemann and Anne Lummerich designed to collect water from fog in Bellavista, Peru. © Anne Lummerich

Kai Tiedemann (front) and local worker Segundo Velasquez inspect a net in April 2007 that Tiedemann and Anne Lummerich designed to collect water from fog in Bellavista, Peru. © Anne Lummerich

One of ClimatePrep’s primary goals is to highlight unique solutions to some of the toughest challenges presented by climate change. This week we would like to draw attention to a project in Peru that combines an old technique for gathering water with modern technology to develop a low cost solution to dwindling, and costly, water supplies for a suffering hillside community.  

The cheapest place to live near Lima is on the steep hills at the edge of the city. The hillside village of Bellavista has attracted people from all over the country, mostly farmers looking for a cheaper way of life. The newcomers who settle in this area build shacks on unclaimed land. If they stay long enough, and plant enough trees to fend of the dangerous landslides, they can obtain government issued title. Unfortunately, the region has a serious lack of freshwater. Lima only gets about 1.5 centimeters a year and as a result the city relies heavily upon glacial melt from the Andes Mountains. Unfortunately, the glaciers have been receding at an alarming rate and according to climate models this trend will only increase. The lack of water available has meant that planting and irrigating the trees has become extremely difficult for longtime residents as well as newcomers. Additionally, the lack of reliable water resources means that the villagers are spending ten times the amount that city dwellers spend on water for cooking, cleaning, and drinking as it must be transported up the hills on a weekly basis. Kai Tiedemann and Anne Lummerich, two German biologists who run Alimón (a small nonprofit that supports Latin American development) have decided to implement a unique solution.

Between June and November, a dense fog sweeps in from the Pacific Ocean and engulfs the steep, dry hillside with the very water the residence so badly need. The challenge resides in harnessing it in some way.

Surprisingly, the answer has actually been around for centuries- fog harvesting. According to Robert Schemenauer, of FogQuest, rain starved communities have long employed the practice of harvesting fog that collects and drips from trees. What is unique aboutTiedemann and Lummerich’s methodology is the ultraefficient nets which literally scoop the water out of the air.

The technique is quite simple: wind blows the heavy fog through the nets where tiny droplets stick to the coarse woven mesh. As more droplets stick to the net they clump together and form larger, heavier drops which eventually fall into a gutter. One net alone, is able to collect as much as 568 liters in a single day. At this point the community has been able to collect as much as 94,635 liters of water via the fog harvesters they have installed.

“At the beginning,” Lummerich said, “the people from the village thought Kai carried the water uphill during the night to fill the tanks, because they couldn’t believe there was so much water.”

Now people can plant the Tara trees needed to obtain the title to the land they live on and have enough water for other purposes as well. The healthier trees

also provide additional benefits.  The fruit from the Tara trees can be sold, providing a regular source of income needed to maintain the nets. As these same trees develop, they too begin to collect water which is now being collected by the community via a series of funnels and tiled channels.

The experience has been so successful that two nearby villageshave already set up similar projects, while Lummerich and Tiedemann hope to develop additional projects in dry communities in Peru.

This story was first reported by Helen Fields for National Geographic Magazine. The information, quotes, and pictures in this blog entry were repurposed from her original report. For additional information on this project we suggest you read her complete article which can be found here.