Source of odour pollution suspected to be from industrial area - Zaini Ujang

He said the odour pollution caused the water at the Indah Water Konsortium (IWK) sewage treatment plant GBK 225 at Taman Velox to turn red and release a rotten onion smell.

The ministry believed that there was an industrial concern in the vicinity that is producing a red coloured effluent responsible for the odour pollution, he said.

"The IWK plant can only treat water from residential areas and not industrial liquid.

"The plant can’t treat water now because irresponsible parties have dumped industrial waste into the sewerage system that cannot be handled by the plant,” he told reporters at the affected treatment plant yesterday.

Zaini added that the ministry successfully trapped the industrial effluent and clean-up work at the treatment plant was currently underway.

“What we will do this evening is to close the plant fully and remove the red coloured water from the plant,” he said.

He also ordered that the water at the plant to be drained and sent to other plants for treatment because there was odour in the drains surrounding the plant.

“The plant has ceased operations, yet we have found small discharges from the plant spilling over to the nearby drains because the plant is already 10 years old, and there might be leaks,” he said.

He added that the Selangor Water Management Authority (LUAS) has implemented a deodourising measure by placing 37 bags of activated carbon to handle the pollution in the drains at the location.

Meanwhile, the Selangor Environment Committee chairman Hee Loy Sian said LUAS activated the Bestari Jaya Water Pool Pumping Operation, capable of pumping 192 million litres per day (mld), as well as the release of water from the Sungai Tinggi Dam (500 mld) and the Sungai Selangor Dam (300 mld) to increase the dilution factor.

Hee said LUAS also raised all the river gates at the Bestari Jaya barrage for flushing purposes and to increase the flow downstream.

He said the Rantau Panjang water treatment plant had to cease operations at 12.20 pm because odor pollution readings of 8 Threshold Odour Number (TON).

Hee said that he expected the TON readings at Sungai Selangor Water Treatment Plant Phase 1, 2, and 3 to return to zero late tonight and that LUAS and other agencies were doing their best to dilute the odour pollution.

Bernama yesterday reported that the pollution caused an unscheduled water disruption affecting 1,139,008 consumer accounts in the Klang Valley. The water disruption covered 1,279 areas in Kuala Lumpur, Petaling, Klang, Shah Alam, Kuala Selangor, Hulu Selangor, Gombak and Kuala Langat starting from 6 pm.