Identification of potential strategic sites for city planning based on water quality through GIS-AHP-integrated model

Freshwater is one of the most important resources for the ecosystem's sustenance and any nation's development. However, clean water bodies are exploited to cater to urban societies' growing demands and economic expansion. This has led to the scarcity of clean water on the planet since the last decade, which is a crucial environmental concern in the present time. Therefore, proper water quality assessment and better management plan integrated with city planning have become an essential need of the hour to combat the clean water stress problem. This study aims to frame a model to identify the potential sites suitable for water use and document an effective development plan for a highly industrialized, populated, planned, and critically polluted city. The potential strategic sites were identified based on the impact of water quality on factors such as human health and economy, which are directly linked to drinking, irrigation, fisheries, as well as industrial production. The relative importance of each criterion (weightage) was estimated using the analytical hierarchy process (AHP). The physico-chemical parameters of groundwater and surface water of the strategic locations were analyzed to calculate multi-purpose water quality index (WQI) and Ryznar suitability index (RSI). These indices were interpolated through a geospatial tool and reclassified using a scoring system to a uniform scale. These thematic maps were weighted overlaid through the GIS model builder tool in GIS interface to develop suitability maps through developed potential site index (PSI) of the ground as well as surface water. The final suitability maps were used to identify the potential strategic sites for various uses such as drinking, fishery, irrigation, and industries, which can be considered by the planners for improvising the city planning. Various management practices were also drawn through these maps, which will safeguard human health as well as the environment.