KARACHI: As the city received over 320 millimetres, or 12.5 inches, of rain during five spells during this year’s monsoon season, authorities are now calculating the damages the wet spell caused to the ill-maintained civic infrastructure and have found that the sewerage network has been affected the most as its lines caved in at 170 key points.

Recently compiled data shows that the heavy rains in Karachi did not only claim the lives of many people, mainly due to electrocution, but the rainfall also battered the fragile infrastructure of the city that could take months to fix, leaving many city roads inundated with sewage.

The key reasons, officials said, behind the damage was below-capacity functioning of the major storm-water drains.

Karachi has received over 320mm of rainfall during the recently ended monsoon season

“There are 38 major storm-water drains running throughout the city, which play a key role during the rainy season,” said a source citing the recently compiled data. “It emerged that complete de-silting and cleaning work of storm-water drains were not done before the monsoon in most cases which led to this situation. We see when rainwater starts accumulating on roads due to non-functioning of the drains, people on their own remove the covers of manholes which are basically meant to carry sewage.”

As a result, he said, sewerage lines started to give in. This situation was experienced every year during the rainy season but this year’s monsoon had made it worse.

“The initial findings of the survey suggest that the city’s sewerage lines have sunk [at] 170 key points, which have been causing heavy outflow of sewage and damaging the infrastructure, mainly roads,” he said. “The repair of the lines will cost heavily and would also put a separate financial burden on the Karachi Metropolitan Corporation (KMC) and the provincial government for repair of roads in their respective jurisdictions.”

He said Karachi’s sewerage lines, from four to 60 inches diameter, came under severe pressure during rains as the system was not designed or built to carry both sewage and rainwater.

“So every year, before the monsoon or any rainy season, depending on the forecast of the Met Office, civic bodies lay out a plan to clean storm-water drains so the city infrastructure could remain safe from the downpour,” he said. “This year too the KMC and other civic agencies were asked to complete de-silting and cleaning work of the drains in their jurisdiction by June 15.

“At a meeting chaired by the Karachi commissioner, the deputy commissioners were asked to monitor the garbage removal work being carried out by the Sindh Solid Waste Management Board and district municipal corporations and to check the complaints of dumping of garbage into the storm-water drains. It was decided that there must be some special arrangements by departments concerned to discourage this practice.”

However, the source said, despite efforts from the authorities concerned the drains were not cleaned to their original capacity putting burden on the sewerage system.

“That’s the reason that several city areas, streets and even key roads have been inundated with sewage. It would need a proper campaign to fix the problem. The repair of several lines has already been started and it could take another few weeks to complete the job across the city,” the source added.

Published in Dawn, October 3rd, 2019