Page 257 - C:\Users\am_se\OneDrive - Higher Education Commission\Desktop\FlipBook\

International Conference on

Recent Trends in Environmental Sustainability

ESCON22/SAgri/34

Groundwater vulnerability evaluation based on Modified DRASTIC Model and its
relationship with groundwater arsenic and water table in Lahore
1*
Syed Umair Shahid and Javed Iqbal 2
1 Centre for Integrated Mountain Research, University of the Punjab, Lahore
2 Institute of Geographical Information Systems, National University of Sciences and
Technology, Islamabad

Correspondence: umair.cimr@pu.edu.pk
Abstract

Metropolitans in the developing countries are facing a menace of deteriorating drinking water
quality. Lahore is the second largest mega city of Pakistan and is confronting a challenge
regarding the availability of clean drinking water for its rapidly increasing population. The
study was performed to create a vulnerability map based on modified DRASTIC model and
assess the distribution of groundwater arsenic in Lahore City. The groundwater arsenic
concentrations data (n = 446) from Water and Sanitation Agency tubewells was acquired to
analyze the water quality. ArcGIS spatial analyst and geostatistical analyst were used for
computing the modified DRASTIC model and mapping the water quality. The modified
DRASTIC model revealed that 51.38%, 36.77%, 9.48% and 2.37% area could be categorized
in terms of vulnerability as low, moderate, high and very high, respectively. The 'high' and
'very high' vulnerability classes were found in the western parts of Lahore. The groundwater
arsenic concentration map also showed higher values in the north-western parts while in the
eastern parts of the study area, the arsenic concentrations had a decreasing trend. In Ravi Town,
the arsenic concentrations were positively correlated with modified DRASTIC vulnerability
index and inversely correlated with water table depth (p < 0.01). It is recommended that the
arsenic removal plants should be installed at all the tubewells with higher arsenic levels (arsenic
concentration > 50 ppb) to provide safe drinking water to the citizens of Lahore. Moreover, the
geospatial techniques used for vulnerability mapping and analysis of water quality could be
applied in other mega cities as well for better monitoring and management of drinking water
quality.

Keywords: Modified DRASTIC, GIS, arsenic, groundwater vulnerability, correlation

Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus

224