METHODOLOGICAL PROPOSAL FOR AREAS SELECTION TO LOCATE UNDERGROUND DAMS USING THE GEOGRAPHIC INFORMATION SYSTEM
Semiarid; Water resources; Thematic Maps
Underground Dams (UD) are used for water storage in the semiarid regions and contribute to the coexistence with water scarcity in rural areas. The traditional location of a UD is guided by basic methods, executed in field surveys, not always guided by a previous study on a regional scale. This work proposes the use of Geographic Information System (GIS), as a research tool applied to smallest scales, seeking potential areas to locate UD. Criteria have been used, according to the required characteristics for the installation of a UD, for which georeferenced data were available, or that could be acquired through the interpretation of satellite images. It was chosen the perimeter of the Potengi River Basin (PRB) as the initial boundary, where information on climatic conditions, lithotypes, land use, hydrography and slope were applied. The subsequent reduction of the area occurred based on the information collected from the water bodies, followed by the classification according to the data of buildings, and drainage related to the deformational structures. Thematic maps of the PRB area and the other delimitations were made. The gradual application of the requirements reduced the studied area by 88%. The method selected ten areas that meet the adopted criteria, taken as the highest probability of success in the implementation of a UD. The GIS allowed the construction of a database that can be adapted to other scales, and receptive to insert new information. It is recommended to use this method as a step preceding field surveys.