'Water is Life' - Groundwater exploration in Western Sahara to support MINURSO
Posted: Friday, 12 October 2012, New York | Author: UN Global Service Centre
Recent climate changes have exacerbated chronic water shortages in arid environments. MINURSO, the UN mission in Western Sahara, has experienced difficulties in providing water to its remote Team Sites. MINURSO requested the technical assistance of the Global Service Centre's-Geospatial Information Systems Centre (UNGSC-GISC). The study used satellite imagery and spatial analysis and modeling to locate groundwater at depth. One productive well has been drilled and others are expected shortly.
UN Team Site Bir Lahlou is located in a remote area in the northeastern part of Western Sahara. The water needed at the Team Site is provided by transporting bottled water from over long distances, with associated high cost and significant environmental impact. Sometimes, the Team Site uses water from a local well with a limited capacity that has drastically reduced in recent times. In order to reduce costs, minimize the environmental impact of the Team Site, and provide additional water to the local population, MINURSO decided to locate new water resources in the area surrounding Bir Lahlou Team Site.
The climate of the area is very arid and the outcropping rocks have a limited capacity for groundwater storage. This combination of negative factors potentially makes the drilling of new water wells extremely expensive, considering the potentially high number of dry boreholes which is typical of an unguided drilling campaign. MINURSO requested the technical assistance of the UNGSC-GISC to undertake a groundwater assessment study, to enhance the likely rate of success of a 'targeted drilling' campaign, and thus reduce the overall cost of the operation. MINURSO GIS, Engineering, and Landmine Action provided support for the conduction of the geophysical field survey and drilling of boreholes at the recommended sites.
The project started with a desk-based study of the area using high resolution, multi-spectral satellite imagery. Processing and interpretation of the satellite imagery resulted in identification of geological features and derivation of hydrogeological images. These were used to recognize geo-indicators of groundwater and locate potential sites for drilling. GIS tools were used to produce detailed maps of the areas to be surveyed.
In January 2012, two GSC GIS centre staff members were deployed to Bir Lahlou area to conduct on-site subsurface exploration. The field survey confirmed the results of the desk study.
In July 2012, the first productive water was drilled. This success lays the foundation for further groundwater exploration, and the generation of additional wells in MINURSO to sustain the mission's operations and enhance the livelihood of the local population. Moreover, productive wells will significantly reduce, or may completely eliminate, the transportation of bottled water to remote Team Sites, as well as minimizing the environmental impact.
Thus, MINURSO could save the high cost of transporting water and of the environmental restoration of its Team Sites.