Seminar told indiscriminate extraction of groundwater paves the way for peril
Within a few years, sea water intrusion from the south might reach Dhaka and make its groundwater salty, if proper measures are not taken, speakers at a seminar said yesterday.
“The saline water has reached up to Magura. Once the groundwater of the capital becomes salty, the place will turn uninhabitable due to lack of fresh water,”said groundwater and irrigation expert Eftekharul Alam.
He was giving a presentation at the seminar organised by Bangladesh Poribesh Andolon (Bapa) at Reporters’ Unity auditorium in the capital.
Eftekharul said the fact of advancing saline water became known after a research by Bangladesh Agricultural Development Corporation (BADC) in 2010 when the groundwater of Dhaka was 170 feet below the sea level.
The researchers estimated sea water intrusion by analysing salt density in groundwater extracted from 200 feet below the sea level from coastal areas up to Magura, he said, adding that salt density at several places in Bagerhat and Khulna had increased in the last two years.
“But we do not know what is happening below 600 or 700 feet, as the BADC does not have any well that deep in the southwest region. So we do not know the pace of the intrusion towards Dhaka. To work that out, it needs an extensive research,” he said.
According to Eftekharul, over extraction of groundwater for irrigation and drinking is mainly causing the sea water intrusion. Use of groundwater for industries in Gazipur, Bhaluka and Mymensingh is making the situation even worse.
The groundwater in Dhaka city was declining every year at a rate of three to six metres, he said, adding that recharging the aquifer with fresh water would improve the situation.
The BADC has taken initiative to install this year some deep tube-wells in the southern part of the country to measure the salinity level which would give an idea about the pace of sea water intrusion.
Feroze Ahmed, vice-chancellor of Stamford University and also a vice president of Bapa, moderated the seminar.
He said the BADC research was conducted mainly based on some limited data and hypotheses. An extensive research was needed to come to a conclusion on the issue.
The government had taken up some projects to supply surface water to the capital which would reduce the dependency on groundwater, Feroze said, adding that there were much more to be done.
Wasi Kabir, an irrigation and water management expert and executive chairman of Bangladesh Research Council, suggested launching an awareness campaign to reduce wastage of groundwater in irrigation, industries and daily use.
Bapa secretary Abdul Matin also spoke in the session.
-With The Daily Star input
