While the Karnataka government’s water diversion project is expected to reduce the flow of the Mhadei river into Goa, there are concerns that the diversion could not only result in a water paucity in major parts of the state but also lead to water contamination on account of an increased concentration of chemicals.
A team of researchers from the Miramar-based Dhempe College of Arts and Science are attempting to ascertain this phenomenon in a project that has received sanction and grants amounting to approximately 7 lakh from the University Grants Commission (UGC).
The proposal for the major project was accepted by the UGC this month under the title ‘Environmental impact assessment of ground water quality of Mhadei river basin with respect to microbiological, chemical and geological parameters.’
“Till date there is no data available on the ground water quality of the Mhadei river basin. If the Karnataka government constructs the dam tomorrow, we will not know what the impact on the ground water quality and environment has been. If the dam or dams do come up, based on the data we collect now we will know the variation that has taken place,” said assistant professor, Manoj Ibrampurkar, who is investigating the geological parameters in the project.
The team, under principal investigator and acting principal at Dhempe College, Yasmin Modassir, will carry out their study during the pre-monsoon, monsoon and post-monsoon season for three consecutive years.
“The reduced flow of water is likely to increase the concentration of chemicals present in it. Our study will be able to establish whether the water is fit for consumption then, among other things,” Modassir said.
The team has identified several wells located in densely populated areas of the Mhadei river basin to test them for their water quality.
“Chemicals used in agriculture are one of the major reasons for pollution of ground water. We want to understand the current status with regard to such chemicals so that Karnataka does n’t later claim that the water pollution, if any occurs post construction of the dam, has not been caused due to water diversion,” said Varsha Virginkar, associate professor, who will study the chemical aspects in the project.
“The Mhadei diversion project will hamper the flow of water in Goa and will mainly affect Sattari, which is dependent on it for domestic as well as agricultural purposes,” Ibrampurkar said.
He said that the River Mandovi has been regarded as the lifeline of Goa as it drains over 43% of the state’s surface area. Moreover, a large part of Goa’s population depends on its water for drinking purposes.
Incidentally, the River Mhadei is one of the important tributaries that originates in Karnataka and flows down the Western Ghats to enter the Sattari taluka and drain into the Mandovi.
“The stop of the flow of the river in Goa would have a marked impact on the water table level in its region of flow. This will adversely affect the local water sources like wells, and, also to some extent, the ponds and lakes in that area. The geological topography of that region would also be affected. There is a need for an investigative study of the water quality for this reason,” said Ibrampurkar.