Dhaka City Corporations: Measures not enough to check waterlogging

Dhaka continues to grapple with waterlogging during the monsoon as different measures taken by the two city corporations have failed to make any substantive contribution to improve the city's drainage system.

To check waterlogging, Dhaka South City Corporation has taken up a project to recover, clean, and re-excavate four canals -- one each in Kalunagar, Zirani, Manda, and Shyampur. Nearly a year after the 898-crore-project was approved by the Executive Committee of the National Economic Council, no visible progress has been made in reclaiming any of the canals.

Talking to this correspondent, DSCC spokesperson Abu Nasher said, "The project has been approved by Ecnec, and we have already started the recruitment process for consultants. Work will begin shortly after that."

The two city corporations officially took over the responsibility of the city's canals and drainage management from Dhaka WASA on December 31, 2020. The aim of the change in custodian was to reduce waterlogging.

Dhaka North City Corporation has submitted a similar proposal to re-excavate canals with the aim of addressing waterlogging issues. The DNCC project, which awaits approval at Ecnec, has proposed to reclaim the Baunia canal, the Kurmitola canal, and the Mirpur Sangbadik Colony canal.

As far as managing the canals and the drainage system is concerned, the city corporations' most visible initiative is the routine work of removing garbage from the canals and drains, which experts believe fall short of preventing the drainage system from being clogged.

Before being the custodian of canals and drains, the various projects the two city corporations carried out from 2016 to 2020 included de-cluttering of canals, canal-drains, and box culverts, and removal of accumulated waste, said several engineers at the DSCC and DNCC, on condition of anonymity. The corporations spent around Tk 1,300 crore on those projects, they added.

But those measures did not yield any desired result as after a few days of cleaning, things went back to square one as the canals got clogged with waste again, they also said.

Waterlogging remains to be a perennial problem in the city as a result. On Thursday night, commuters experienced a night of horror as major parts of the capital went under water after 113 millimetres of torrential rain, disrupting people's movement and triggering massive traffic chaos.

This monsoon, the city dwellers had similar experiences on at least two other occasions -- on July 1 and August 9 -- when vehicles were stuck on inundated streets for hours.

Experts say a comprehensive and sustainable drainage network is urgently needed for a lasting solution.

Rainwater should naturally flow into water bodies and open and underground drains should also carry water to canals that lead to the rivers, they said.

"The drainage system in Dhaka city is inadequate. Even normal rainfall exceeds its capacity, let alone a rainfall of 113 millimeters, which is quite substantial," Prof Md Mujibur Rahman, a teacher of civil engineering department at Bangladesh University of Engineering and Technology, told The Daily Star.

Additionally, the drainage system's design is not up to the mark. It explains why the storm drainage capacity is overwhelmed due to various types of waste. All these reasons contribute to clogging the system, he stressed.

"If we can free all the canals from encroachments and re-excavate them properly, water will flow away quickly," Prof Mujibur said. He suggested modernisation of the drainage system should be done after taking into consideration the changes in the weather pattern.

Currently, Dhaka has a network of 2,211 kilometres of drains, with 961-km in the south and 1,250-km in the north part of the city.

When WASA looked after the canals, efforts primarily focused on open drains. However, the ongoing efforts by the city corporations encompass both canals and drains, requiring substantial financial allocation, said sources at the DSCC and DNCC.

DSCC Mayor Sheikh Fazle Noor Taposh said infrastructure was developed in 136 locations in the last 3 years at a cost of Tk 225 crore from their own funds.

"Of those locations, sewerage infrastructure was developed in 103 places," he said.

DNCC Mayor Atiqul Islam claimed that the situation has improved significantly because of various measures they have taken.

"Even if it rains heavily, water does not collect anywhere for a long time as before," he said.