GIS BASED GEO HAZARD ASSESSMENT OF PAKISTAN FOR FUTURE URBAN DEVELOPMENT USING AHP

Abstract

<p>Pakistan has been subject to frequent earthquakes, which are often severe (especially in the north and west), and severe flooding along the Indus River after heavy monsoon rains (July to August every year). Loss to life and property as a result of these natural disasters has been very high in the recent past. In order to mitigate these losses, an integrated decision support which could help planners make complex decisions accurately and quickly is required. This first ever study aims to provide a multi criteria decision analysis framework resulting in the regionalization of the territories of Pakistan according to the level of vulnerability to these natural disasters. Site suitability for urban development in Pakistan was assessed by the application of GIS and the Analytical Hierarchy Process (AHP). GIS can effectively store, retrieve, manipulate, analyse and display the spatial in site selection problems. AHP can be used to calculate weights of criteria while the decision maker remains consistent in judging and allocating comparative preferences to criteria. Weighted scores were aggregated in two clusters namely environmental (elevation, slope, aspect, distance from rivers, land surface temperature and precipitation) and hazard (flood extents, earthquake density and intensity). The results of these two clusters were then synthesized using an innovative scheme to obtain a suitability index map. Indices in the map were classified into four categories representing extremely suitable, suitable, less suitable and worst regions for urban development. This study shows how an effective multi criteria decision support method can be developed to select suitable sites for urban development in order to reduce exposure to natural disasters. Urban development should be planned in extremely suitable areas. </p>