Could fog become a viable source to produce drinking water?

With climate change posing a threat to the global supply of freshwater, water scarcity is becoming a growing concern. Moreover, in many areas around that experience drought, the burden often falls on women to travel long distances to access fresh water for themselves and their family. In light of these concerns, researchers are exploring the potential of fog harvesting technology as a key to making drinking water more accessible to rural and isolated communities.

Image from: https://www.bbc.com/news/world-latin-america-32515558

What is Fog Harvesting?

Fog harvesting is the collection of water droplets contained in fog and mist. Regions such as the Sahara desert in Morocco and the Atacama desert in Chile are some of the driest areas in the world and receive very little rainfall. However, the lack of rain is supplemented by heavy fog that blankets the area for several months of the year. 

Fog catchers have been installed in these regions to harness wind-driven fog as a source of freshwater. When fog rolls in, water is captured by large mesh nets. The water droplets then drip down the nets into a trough and carried through a pipe to the local community. The water can be consumed as drinking water, raising livestock, and other domestic uses such as cultivating plants and washing clothing. Although this innovative technology may seem like a new invention, the technique has been used for centuries and is also found in nature. These nets mimic ecological processes in some species of plants, trees, moss, lichen, and even beetles, which are able to survive in desert conditions by capturing moisture from fog.

Image from: https://unfccc.int/climate-action/momentum-for-change/women-for-results/women-led-fog-harvesting-for-a-resilient–sustainable-ecosystem

What Impact Does Fog Harvesting Have Globally?

These nets are typically most effective in coastal and mountainous regions with a high presence of fog, and researchers are identifying other areas in which they can benefit communities. Advancements in design are also being made to create new models of fog catchers (such as the fog harp) to improve the efficiency of fog collection.

The CloudFisher in southwest Morocco is the world’s largest fog collector site. The 31 nets provide fresh drinking water to 1600 residents. The project has also improved the livelihoods of the women, who would travel for hours every day to retrieve freshwater. Fog-catching nets have also been installed in Peru, Bolivia, Colombia, Mexico, and Chile, and each net captures 200-400 litres of freshwater per day. These nets have transformed the lives of local families by now making it possible to cultivate agriculture in historically dry areas.

These fog-catching nets have amazing potential to combat drought and water scarcity, which are worsening due to climate change. Advancements in fog harvesting design and technologies will improve their efficiency and can change the lives of more communities around the world. However, technological interventions alone will not suffice in tackling the global water crisis; rather, better conservation and water management must also be coupled with these innovations. What do you think about harnessing fog as a freshwater source? Let us know by tagging us at @SustainableWat!

Video:https://www.youtube.com/watch?v=NBhFxXT9mUQ