BSc-MSc (Integrated)

The study, simulation of salt water intrusion into the coastal aquifers of
Kadalundi river basin in Malappuram district using Visual MODFLOW was to
simulate the saline water intrusion in the coastal aquifers using Visual MODLOW and
to predict the extent of saline water advancement in coastal regions of Kadalundi river
basin. Coastal stretch of Tanur, Tirurangadi and Parappanangadi blocks of the
Kadalundi river basin was selected as the study area which comprises of about 130 km2
drainage area. The area lies in between 11004’5” to 11004’60” N latitude and 75050’18”
to 75057’7” E longitude. In this study, Visual MODFLOW 2.8.1 integrated with MT3D
software developed by Waterloo Hydrogeological Inc. was used for ground water
modelling and contaminant transport modelling. The base map of the study area was
imported into the model in BMP format and divided into 40 columns and 40 rows (1600
cells). Water level and water quality data of observation wells maintained by Central
Ground Water Department in the study area was used as input to the model. Secondary
data on hydrogeological parameters and aquifers properties were also used as the input
parameters for the model.
Visual MODFLOW is regarded as an effective tool for groundwater
resource modelling and contaminant transport modelling. The role of contaminant
transport models in the field of ground water quality and pollutants transport in
subsurface studies was fully affirmed. It was also observed that there was a chance of
saline water intrusion in the coastal stretch of Tanur, Tirurangadi and Parappanangadi
blocks of Kadalundi river basin. It was also predicted from the model study, there are
chances of saline water intrusion to a lateral distance of 0.5 km to 1.9 km from the coast
which extends 3.2 to 4.5 km along the coast from the northern boundary of Kadalundi
river basin. Coconut retting, lime shelling and sand mining activities in Kadalundi river
basin was a potential source of pollution and contaminant transport. Development of
small industries, construction of buildings and agriculture activities in the coastal
stretch of river basin necessitated increased rate of pumping of ground water. This
increased pumping of ground water lead to the entry of salt water into the fresh water
aquifer formations. Global warming and sea level rise are also threatening problems in
the current climate change scenario which is also a reason for saline water intrusion in
to the coastal fresh water aquifers. Groundwater replenishment through natural and
artificial recharge and sustainable development activities in the area are the main
countermeasures to overcome this problem.