Groundwater vulnerability assessment using GIS-based DRASTIC method in the irrigated and coastal region of Sindh province, Pakistan

Abstract

This study aims to evaluate the vulnerability of shallow aquifer in irrigated and coastal regions of Sindh province, Pakistan by applying DRASTIC method in geographical information system (GIS) environment. Vulnerability index values ranging from 119 to 200 were categorized into three contamination risk zones. Results illustrated that 28.03% of the total area that was distributed in the upper northern and southernmost coastal area of the province was very highly vulnerable to contamination, 56.76% of the area was highly vulnerable, while the remaining 15.21% area was in medium vulnerable zone. Single and multi-parameter sensitivity analysis evaluated the relative importance of each DRASTIC parameter and illustrated that depth to water table and net recharge caused the highest variation in the vulnerability index. Two water quality indicators parameters, i.e., electrical conductivity (EC) and nitrate ion (NO3−) were used to validate the DRASTIC index. The spatial distribution map of both parameters showed a certain level of similarity with the vulnerability map and both parameters illustrated significant correlation with the DRASTIC vulnerability index (p < 0.01). This signified that vulnerable zones are particularly more prone to EC and NO3− contamination. Findings of this study will assist local authorities in contamination prevention in the groundwater of the lower Indus Plain.

A Simple Approach of Groundwater Quality Analysis, Classification, and Mapping in Peshawar, Pakistan

“…Many researchers have used the DRASTIC [29] or GIS-based DRASTIC models (overlay and indexed method) [30][31][32][33], MOUSE and RUSTIC models (process based simulation methods) [36,37] for water quality assessment while other have applied the clustering analysis (statistical methods) [32,[60][61][62] in which they simply separated different clusters/groups based on similarity or dissimilarity. The clustering analysis is also used in this study, but the interest was to find out the exact threshold values that separate those clusters, and this makes it different than the other studies.…”

Influence of Agricultural Irrigation Activity on the Potential Risk of Groundwater Pollution: A Study with Drastic Method in a Semi-Arid Agricultural Region of China

“…Water carries surface pollutants into underground aquifers in the infiltration process, which induces groundwater contamination. The net recharge R is positively correlated with the groundwater vulnerability and pollution risk [38]. Therefore, it is important to accurately calculate the value of R, especially when there are multiple supply sources.…”

“…Hydraulic conductivity (C): The hydraulic conductivity is a very important aquifer parameter, which controls not only the hydraulic transport capacity of the aquifer, but also the flow path of pollutants [38]. It also controls the rate of infiltration, as well as the movement of groundwater.…”

Mapeamento da vulnerabilidade natural das águas subterrâneas do município de Jaguarão/RS

“…Por conseguinte, os métodos COP (Flow Concentration, Overlying layers, Precipitation) e PI (Protective cover, Infiltration conditions) que são especificamente usados para ambientes que possuem características cársticas, sendo o método COP usado no estudo de vulnerabilidade do sítio cárstico de Shimbar (BAGHERZADEH et al, 2018). Ademais, tem-se o supracitado método DRASTIC (Depth to water, net Recharge, Aquifer media, Soil media, Topography, impacto vadoze zone media, hydraulic Conductivity of the aquifer) que considera a dinâmica de movimentação dos poluentes, utiliza-se um elevado número de parâmetro, o que em muitos casos inviabiliza sua aplicação (SHAHAB et al, 2018).…”