IWK said its operations team inspected the site following a complaint by Zone 9 city councillor Ramu Nadarajan and found that the main cause of the overflow in drains and ditches was poor maintenance.

“The drainage system was clogged with rubbish, sediment and tree roots, which obstructed water flow,” the company said in a statement today.

As a result, treated effluent from a nearby sewage treatment plant and rainwater from the residential area could not drain properly.

IWK said the area’s low-lying topography and proximity to Sungai Klang also contributed to frequent flooding.

It said the existing sewerage infrastructure and treatment plant, which have been in operation for over 30 years, were built based on technical plans aligned with the area’s original development design.

“The discharge route for treated effluent has remained unchanged since the plant was built,” it said.

IWK said two aerated lagoon-type sewage treatment plants served the neighbourhood and both were operating within their designed population equivalent capacity, with no signs of overloading.

It said its findings had been shared with the Zone 9 councillor and the Shah Alam City Council (MBSA).

Earlier, SelangorKini reported that Ramu had urged IWK to redirect the treated discharge, claiming the existing route was contributing to repeated floods in the area.