Spatial Variability of Groundwater Depth and Quality Parameters in the National Capital Territory of Delhi

Abstract

The groundwater quantity and quality scenario is of much concern in the National Capital Territory of Delhi, India, which necessitates an investigation to envisage the extent of spatial variability of groundwater depth and pollutant concentration levels in this region. Therefore, in this study, an effort was made to generate the spatial variability map of groundwater depth and quality parameters (viz. chloride, electrical conductivity, fluoride, magnesium, and nitrate). Ordinary kriging was used to analyze the spatial variability of groundwater depth and quality parameters, whereas indicator kriging was used to analyze groundwater quality parameters equal to or greater than the pollution threshold values. It was observed that the semivariogram parameters fitted well in the exponential model for water depth and in the spherical model for water quality parameters. The generated spatial variability maps indicated that in 43% of the study area, groundwater depth was within 20 m. The salinity level was higher than 2.5 dS m(-1) in 69% of the study area and the nitrate concentration exceeded 45 mg l(-1) in 36% of the area. The probability maps showed that about 24% of the area had the highest probability (0.8-1.0) of exceedence of the threshold electrical conductivity value and an area of 2% exhibited the highest probability of exceedence of the threshold value of nitrate concentration in the groundwater. The generated spatial variability and probability maps will assist water resource managers and policymakers in development of guidelines in judicious management of groundwater resources for agricultural and drinking purposes in the study area.

Association of sociodemographic and nutritional factors with risk of neural tube defects in the North Indian population: a case–control study

“…Various studies also reported in 2011 that agricultural activities in the northern or central part of India resulted in a high concentration of nitrate or fluoride in groundwater, making it unsafe for drinking (25,26) . Moreover, a study in 2010 reported high nitrate concentration in groundwater in the study area of Delhi (27) and it was observed in the present study that more case mothers had migrated from rural areas of northern and central parts of India to Delhi. This is reflected in the fact that the women in our study who used more groundwater for drinking, which involved potential exposure to contaminants, had a higher risk of having children with NTD.…”

Implementation of GIS and Geographic RDBMS Prototype for Water Resources Management. Zeuss-Koutine Basin (South of Tunisia)

“…These various groundwater aquifers (Figure 3) form hydrogeologic multi-layer entity where the relays are ensured by faults and vertical drainage [12]. Ben Baccar in 1982 has estimated the flow of the water pumped to 212 l/s and the minimum average flow sources to 5 l/s when the fictitious continued flow is 350 l/s.…”

Hydrological Modeling Using GIS for Mapping Flood Zones and Degree Flood Risk in Zeuss-Koutine Basin (South of Tunisia)

“…Input to the batch subwatershed delineation function is a point feature class with point locations of interest [29]. The Batch Point Generation function can be used to interactively create such a file.…”