GIS Based DRASTICA Model for Assessment of Groundwater Vulnerability in Bengaluru Region, India

Authors

  • Shwetha A ., Dr.Sampath Kumar M. C ., Dr.Rajyalakshmi M

Abstract

Groundwater pollution is a common problem in urbanized zones and agricultural belts, causing
severe health hazards to human and animal populations. Groundwater pollution is generally intensified when
storage is decreased. This paper aims to assess the groundwater pollution vulnerability, which is an essential
tool for the protection, development, and management of groundwater resource zones. The study is carried
out in the Bangalore region of Karnataka state, which is geographically located between 12.40° N to 13.20°
N latitudes and 77.30° E to78.00° E longitudes and covers an area of 1617.12 sq. km. Groundwater pollution
is a significant problem in the study area because aquifers are constantly vulnerable to land use change
driven contamination and other anthropogenic activities. Groundwater vulnerable zones are optimized in the
study by integrating the Anthropogenic Influence Factor (A) to the existing DRASTIC model using the GIS
based Analytical Hierarchy Process (AHP). The modified DRASTIC model is termed as ‘DRASTICA’. The
concentration of nitrate has been measured for pre-monsoon and the post-monsoon seasons of the year 2017,
totally covering 110 sample locations. The nitrate spatial variations have been correlated with the
groundwater vulnerability datasets obtained from the DRASTICA model using the Inverse Distance
Weightage (IDW) technique. Totally, four pollution vulnerability categories have been identified in the
study area which include very high, high, medium, and low vulnerable zones. Results indicate that about
14% of the study area falls under very high category whereas about 21% falls under high category. The very
high and high categories are mostly distributed in Bangalore East and Anekaltaluks encompassing eastern
south-eastern and southern parts of the study area. It can be concluded that the DRASTICA model could be
very useful to assess the pollution vulnerability especially in urbanized and agrarian zones where land use
pattern changes continuously.

Published

2020-01-31

Issue

Section

Articles