The country’s ecological balance will be under threat as the aquifer in some regions is going down due to excessive and unplanned extraction of groundwater. The groundwater level in Dhaka, Gazipur, Mymensingh, and Barind regions has declined at an alarming rate in a couple of years due to the expansion of industrialisation. As Barind and central regions of the country are located upstream from sea level, a massive fall of the aquifer in those regions will cause salinity intrusion in the entire southern region and destabilise agriculture productivity and ecological balance.
Dependency on groundwater over a long period has taken a toll on the groundwater level in Dhaka. According to 2030 Water Resources Group, the annual water decline rate for Dhaka city is 3 metres per year. If the demand increases, which is likely, then this can reach up to 3.9 metres per year this year and 5.1 metres per year in 2030. If any preventive measures are not taken groundwater levels will fall to 100 to 150 metres by 2050. Dependency on rainwater will help the deep aquifer to hold on to the limited water it has. Groundwater weighs down the Earth’s upper crust. If the groundwater falls below a certain depth then the crust is lifted. This shift aggravates the fault line, which in turn can trigger earthquakes in the area.
The groundwater table of the capital has dropped in recent years as WASA installed more deep tube wells every year to quench the thirst of the ever-increasing number of residents of the world’s one of most densely populated city. According to WASA, around 80 per cent of its supply comes from groundwater extracted through 805 deep tube wells and around 20 per cent from four plants that treat surface water at Sayedbad and Chandnighat in Dhaka and Godnail and Sonakanda in Narayanganj.
The groundwater depletion rate will accelerate further in the coming years as a rapidly growing population withdraws groundwater at higher rates than replenishment. Enough is enough. For our generations and coming generations, we must refill the groundwater level and encourage surface water by treating river waters and rainwater.
