Drinking water quality assessment of river Ganga in West Bengal, India through integrated statistical and GIS techniques.

An attempt has been made to assess the water quality status of the lower stretch of river Ganga flowing through West Bengal for drinking using integrated techniques. For this study, 11 parameters at 10 locations from Beharampur to Diamond Harbour over nine years (2011-2019) were considered. The eastern stretch of Ganga showed a variation of Water Quality Index (WQI) from 55 to 416 and Synthetic Pollution Index (SPI) from 0.59 to 3.68 in nine years. The result was endorsed through a fair correlation between WQI and SPI (r2 > 0.95). The map interpolated through GIS revealed that the entire river stretch in the year 2011, 2012, and 2019 and location near to ocean during the entire period of nine years were severely polluted (WQI > 100 or SPI > 1). Turbidity and boron concentration mainly contribute to the high scores of indices. Further, the origin of these ions was estimated through multivariate statistical techniques. It was affirmed that the origin of boron is mainly attributed to seawater influx, that of fluoride to anthropogenic sources, and other parameters originated through geogenic as well as human activities. Based on the research, a few possible water treatment mechanisms are suggested to render the water fit for drinking.

Groundwater quality assessment in an industrial hotspot through interdisciplinary techniques.

Dependency on groundwater has increased due to unprecedented growth of industries as well as settlements. Therefore, assessment of groundwater quality to determine its impact on human and environment has become essential. The major objective of this study was to frame a methodology for complete assessment of groundwater quality in a highly industrialized area comprising of iron, steel, fertilizer, cement, chemical, heavy machinery manufacturing, thermal power, coal mining, and allied industries. Physico-chemical parameters of water samples were analyzed from strategic locations during pre- and post-monsoon seasons. The primary analysis through the water quality index showed 50% of the sampling locations in pre-monsoon and 65% in post-monsoon seasons have very poor quality. Hence, the health risk calculated through hazard index indicates that the water is unsafe for drinking. Chemical indices such as sodium percentage, sodium adsorption ratio, residual sodium carbonate, permeability index, and magnesium hazard suggest that the water can be used for irrigation. High corrosivity ratio at 90% sampling locations specifies its unsuitability for use in industrial production. Factor analysis and other statistical methods justified that the pollution of groundwater was attributed to geogenic, as well as anthropogenic, activities. This research demonstrates the usefulness of interdisciplinary techniques for complete assessment of groundwater quality and representation of complex data set into a presentable and understandable form for proper communication with public, regulatory authorities, as well as policy makers, responsible for water management.

Suitability Assessment of Surface Water Quality with Reference to Drinking, Irrigation and Fish Culture: A Human Health Risk Perspective.

A multi-purpose Water Quality Index (WQI) was developed to assess the suitability of surface water for drinking, fish-culture, as well as irrigation in Durgapur industrial city, India. WQI was calculated for 48 sampling locations, where 2.08%, 4.17% and 22.91% of the sampling locations have excellent water quality (WQI: 0-25) and 20.83%, 33.33% and 34.35% have good quality (WQI: 25-50), which represents its suitability for drinking, irrigation, and fish-culture respectively. Further, health risk was evaluated by Hazard Index (HI), which reflected that the population were prone to risk on oral ingestion [HI (female): 1.52; HI (male): 1.29], while safe for dermal contact (HI < 1). Potent toxic pollutants like Co, F, Mn, NO3 were identified to cause health hazards. The pollutants were attributed to rock-weathering, industries, agriculture and municipal sources, was investigated by factor analysis. This novel assessment technique with integration of geographical information system affirmed its effectiveness and easiness to evaluate water quality for multiple uses in any area.

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.