No more deep tube wells in Dhaka

The system employed to meet Dhaka metropolitan’s ever increasing demand for water is risky and lacks foresightedness. Around 78 per cent of the demand is being extracted from beneath the surface.

Dhaka WASA says there are over 900 deep tube wells in the metropolitan. The number of deep tube wells owned by individuals and private entities are over 2500. All these are pumping water from beneath the earth around the clock, which is likely to leave us in danger, experts say.

Excessive use of groundwater results in the water level going down, hampering the ecological balance. It means water becomes less available, further expenses to extract water and the groundwater also becomes more likely to be contaminated.

Secondly, excessive extraction of water increases the probability of a landslide. We all know about these dangers. And that is why we should depend more on water available on the surface than the water that is beneath the earth. Dhaka WASA is also well aware of the fact. They have been saying that setting up deep tube wells has becoming increasingly risky as the water level beneath the surface has gone down.

Taking charge of Dhaka WASA a decade ago, the managing director had said he would take steps to make the best use of river water, instead of setting up more deep tube wells. The reality contradicts his pledges though, around 350 deep tube wells have been set up in the last 9-10 years.

It has resulted in the water level getting about five feet lower every year. As a result, the cost to extract water has increased. About 8-10 years back, the cost to set up a deep tube well was Tk 4-5 million. Nowadays, it has jumped to Tk 12 million. About a decade back, a deep tube well could extract water for 10-12 years, but now they can do that for 2-3 years only. The price of water has increased by 11 times since 1982.

There are five water treatment plants, which is meeting 22 per cent of the demand. However, the water treatment plants is a few times more costly that the deep tube wells.

We need to be less dependent on the deep tube wells and try to make the best use of the other sources. Harvesting the rain water can be a very good alternative in the rainy season. In 2000, the prime minister had passed a directive for the government buildings to conserve rain water, but in 19 years that has not seen any form of implementation. We need both the government and non-government entities to come forward so that we can lower the dependence on groundwater.