Peru Mejia

Peru – Mejia 1995 – 1999

Fog Collection Scientific and Evaluation Project

Update 2009

This major project was undertaken years before FogQuest was formed. The data collected are important in demonstrating the amounts of fog water that can be collected and effectively used on the arid desert coast near Arequipa, Peru. Overall project direction was by Dr. Roberto Semenzato of the University of Padua, who is presently a FogQuest member and supporter.

The five university research units (Arequipa [Peru], Florence and Padua [Italy], Santiago [Chile], with assistance from Dr. Robert Schemenauer from Environment Canada, and Toulouse [France]), after five years of work, fulfilled the main objectives of the research project, namely to verify the possibility of rehabilitation of the lomas ecosystem through reforestation supported by fog water. Preparatory activities were focused on a better knowledge of the environment: meteorology, climatology, fog behavior, flora and fauna, auto-ecological aspects, socio-economic and institutional aspects. Research activities in the field started with a measurement campaign of fog collection in different locations of the study area. After the choice of the Las Chucillas area, the experimental station was built up: 20 large fog collectors, 3 reservoirs, the drip irrigation system, a nursery, a guest house, the experimental plot, fences etc. Growth and survival of planted trees were accurately monitored in the research period. (with and without irrigation support). Other important side-research experiments were performed: identification (with cartographic output) of the various lomas vegetation types, fog collection measurement on planted trees, hydrological survey on some Caesalpinia spinosa forest relics and wind tunnel trials on various kinds of meshes.
The main results of the research may be summarized as follows:

  • the area of Mejía has shown, in the three and a half years of study, to have a very good potential for fog water collection; fog is definitely a water resource that can be used for domestic, agriculture/forestry and ecological purposes in this area;
  • the trees and shrubs in the lomas (coastal hills) can survive with only the water contribution from fog collection;
  • re-forestation without initial irrigation support gives unsatisfactory results in terms of survival and growth of plants;
  • irrigation support may be stopped after two years; at this point the trees had grown enough to capture sufficient fog for their survival;
  • in the experimental conditions (the best place in the area for fog capturing, a reasonable distance between capturing and utilization) the cost of water was, all included, 0.8 US $/m3;
  • in general, the cost of fog water utilization may be justified if no other water resource is available; considering an irrigation rate of the adopted amount of 1 liter per day per tree, two years of irrigation support will cost the reasonable sum of 0.6 US$/tree.

[The above is an edited version of the project summary: “Fog as a new water resource for the sustainable development of the ecosystem of the Peruvian and Chilean coastal desert”, European Community Directorate General XII, Contract Nº TS3 CT94 0324, Final report 1995-1999.]
Papers discussing the results of the project at Mejia can be found in the proceedings volume of the First International Conference on Fog and Fog Collection, 1998, Vancouver, Canada. There is also a CD with results available and scientific papers have been published on the data.

Approximate location this project.

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