Researchers in Chile report that low-tech fog collectors can capture up to 10 liters per square meter per day in fog-rich, elevated sites near Alto Hospicio on the Atacama’s edge. The team estimates about 17,000 square meters (≈4.2 acres) of mesh could meet the region’s weekly water demand, potentially supporting irrigation, agriculture and—with treatment—drinking water for ~10,000 people. Success depends on local fog frequency, elevation and wind; the authors recommend pilot projects, water-quality checks and policy integration as next steps.
Fog Harvesting Could Become a Viable Water Supplement for Arid Coastal Cities, Study Finds
Getty Stock ImagesStock photo of fog over a plain.
As climate change tightens pressure on freshwater supplies, researchers are exploring unconventional and low-cost solutions. A new field study published in Frontiers in Environmental Science shows that simple "fog harvesting" systems can capture substantial water volumes in some of the world’s driest coastal urban areas.
How Fog Harvesting Works
Fog harvesting uses large mesh panels stretched between posts. As fog blows through the mesh, microscopic droplets cling to the fibers, coalesce into larger drops and run down into gutters that channel the water into tanks. The setup is low-tech: it requires no electricity or pumps and can be inexpensive to build and maintain.
Getty Stock ImagesStock photo of fog over grassland.
Field Study Near Alto Hospicio, Chile
Chilean researchers tested fog collectors around Alto Hospicio, a fast-growing city on the edge of the Atacama Desert that receives less than a quarter-inch of rain per year but often experiences dense coastal fog. Over a year-long monitoring campaign, collectors sited at higher elevations captured meaningful water yields. At peak performance, some installations produced as much as 10 liters per square meter per day.
Based on average collection figures, the team estimated that roughly 17,000 square meters of mesh (about 4.2 acres) would be required to meet the region’s total weekly water demand. Under the right conditions, researchers say these yields could support irrigation, local agriculture and, with appropriate treatment and storage, potentially potable supply for communities on the order of 10,000 people.
Getty Stock ImagesStock photo of fog over a mountain range.
“This research represents a notable shift in the perception of fog water use—from a rural, rather small-scale solution to a practical water resource for cities,” said Dr. Virginia Carter Gamberini, assistant professor at Universidad Mayor and the study’s first co-author. “Our findings demonstrate that fog can serve as a complementary urban water supply in drylands where climate change exacerbates water shortages.”
Limitations, Risks and Next Steps
The study highlights important caveats. Yields varied substantially by site: elevated locations with persistent fog and favorable wind patterns produced the most water. Fog harvesting is not a universal remedy and will not be viable where fog is rare or highly variable.
Researchers emphasize additional requirements before scaling up: careful site selection, optimization of mesh design, reliable storage solutions, and water-quality testing and treatment if water is to be used for human consumption. They recommend pilot programs, community engagement and policy integration to assess feasibility, cost, maintenance needs and compatibility with existing supply networks.
Broader Context
Globally, more than two billion people lack access to safely managed drinking water. As climate change and population growth stress conventional sources, low-tech options such as fog harvesting could serve as a complementary, renewable component of diversified water strategies for select arid coastal cities.
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