Fog Water Collection Evaluation in Asir Region–Saudi Arabia

Based on the fact that water can be collected from fog under favorable topographical and atmospheric conditions. The small water droplets present in the fog precipitate when they come in contact with solid objects. The frequent fogs that occur in the southwestern region of Kingdom of Saudi Arabia have the potential to provide an alternative source of freshwater in this otherwise dry region if harvested through the use of simple and low-cost collection systems known as fog collectors. A fog collection project has been carried out in Asir region of Saudi Arabia. Three Standard Fog Collectors (SFC) were designed and manufactured with locally available materials and imported mesh. These SFCs were installed in April 2006. Three different sites were chosen based on topography and altitude and data from April 2006 to April 2007 were obtained. Measurements with the SFCs were made for regions with 2,260 to 3,200 m elevation. The results indicate that at highest altitudes (at Alsooda), it is feasible to obtain an average water production of 6.215 L/m2 day over the studied period, and in the lower altitudes, which are in Abha city, it is possible to collect more than 3.3 L/m2 day. The highest water collection was 24 L/m2 day and recorded in Dec. 20, 2006 at Al-Sahab park station, and furthermore for the same site, the best average water production of 11.5 L/m2 day was obtained in winter 3 months period namely (December, November and January). Data about the weather conditions has been collected for the studied region. An analysis of fog collection effectiveness was carried out and compared with international standards. The obtained results indicate that fog can be a useful source of water supply in the southwest region of Saudi Arabia.