Application of Analytical Hierarchy Process in Topology of Rain Water Collection in Urban Basin (Case study: Birjand City)

Deficiency of precipitation followed by water scarcity is one of the most important problems in arid and semi-arid regions. Among the water supply sources to these areas are collecting and storing rainwater. Site determination is finding a series of proper optional places for a particular applications that multi-criteria decision problem are involved. They are defined by simplified strategies for decisions and facilitate spatial process on various problems of spatial deciding in various ways. The aim of this study is to determine the potential sites of rainwater harvesting using Analytical Hierarchy Process in urban areas of Birjand. In this study, to obtain the proper area for rainwater collection from 5 criteria of slope, annual precipitation, land use, distance from surface canals and rivers in the study area were used. Initially to use this model, layers provided based on their relationship with the phenomenon are classified and scored. Then, they are introduced to the model. The final composition of the layers is configured of four classes, including the potentials of very high, high, medium and low categories. Results have shown that the criteria of land use, distance from river and surface channel take the largest weights of 0.584, 0.151 and 0.140, respectively. Finally, eleven points talented rainwater harvesting in urban areas of Birjand are identified.