The “Fog Catcher” Project – Peru

What is a ‘fog catcher’?
The ‘Fog catcher’ is an invention which serves to trap water drops from fog. In desert areas like the Peruvian coast there is a lack of water and rain, but there is a lot of fog occurrence, mainly in the top of hills or at high places.
A ‘catcher’ is a construction of stems made of metal, bamboo or “Guayaquil” wood and a tight-knit mesh of raffia in between them. The little water drops caught by this mesh are collected by PVC gutters and flow through an organic filter into a tank.

Why are ‘fog catchers’ so important?
‘Fog catchers’ play an important role in obtaining and saving water, particularly in the outskirts of Lima and the coastal cities of Peru where there is hardly any water. Although the resulting water is not drinkable, it is useful for agricultural purposes and washing clothes and household utensils. FogCatcherPeruThe cost of building a ‘fog catcher’ is about $ 500 and can yield up to a small cylinder of 100 liters of water per day, a saving of almost 60% in water usage.
Regarding this, our team decided to adapt this idea (originally it’s the idea of an American NGO in Lima) and went north to the outskirts of Lima, where people do not only suffer from water scarcity but also poverty. We exchanged some of the materials in more affordable things and taught them how to build “fog catchers”. As this project is meant to be adapted, we included a little instruction for you.


Materials to be used

  • 2 ‘Guayaquil’/stems of wood available of 20 feet long (6 meters)
  • Some PVC pipes to catch the water, 4 inches (10cm) worked well for us
  • PVC tubes to connect to the tank, ½ inches (0,7cm) worked well for us
  • 1 water filter
  • Raffia or mesh 13 x 20 feet (4×6 meters)
  • Rope or wire
  • Tank to collect water

Furthermore you need a saw, a hammer and some 3 inch nails (7cm) and a ladder.


  1. Prepare the ground. It must be a flat and firm ground.
  2. Build a pond or buy a tank to catch the water.
  3. Fix the stems firmly to the ground (dig in ¼ of it at least). Place them in a distance shorter than your raffia/mesh is, so that you can fix it well.
  4. Fix the raffia/mesh to the stems. It should look like an advertising panel when you are finished.
  5. Place the PVC pipes under the panel so that caught water will drop into it and will be lead into your tank/pond. Place the water filter before the tank.


This project is an adaption. See here our sources of information:

  • Universidad Nacional Autónoma de México (UNAM) (2009). «La niebla, posible fuente de agua potable». Gaceta UNAM (6). p. 5