Geospatial Analysis Model for Locating Optimum Centralized Wastewater Treatment Plant for Sulaimania City

Abstract

Sulaymaniyah city has no wastewater treatment plant (WWTP) and the sewage is discharged into a stream (Qilyasan Stream) without treatment. Wastewater disposal problem has been a major concern in many developing countries because of the high rate of population growth. The aim of this study is to find the best location for a wastewater treatment plant in Sulaymaniyah city. The city consists of three major areas which are; Sulaymaniyah Central, Bakrajo, Rapareen, and Tasluja. Linear combination Mulita Criteria Decision Model (MCDM) is applied using GIS integrated with Fuzzy Analytic Hierarchy Process (FAHP). In the GIS model nine suitable criteria are used; distance to the agricultural areas, distance to the wells, distance to the sewer outlets, distance to the main roads, the area slope, the area elevation, distance to the water body, depth to the groundwater table and distance to the industrial area. Moreover, two restricted layers are considered; the distance from the residential areas and the distance from other buildings such as; educational buildings, sports centers, commercial areas, and the airport. The buffer distance of the restricted distances is taken 1,220 m. FAHP is used to find the weights of the suitable criteria that applied in the linear combination equation. The result showed five final suitable classifications; not suitable, low suitable, moderately suitable, highly suitable, and extremely suitable.