KUALA LUMPUR, Sept 4 ― Water supply to around 1.2 million user will continue to be affected for another four days due to the contamination at the water treatment plants in Sungai Selangor Phases 1, 2, 3 and Rantau Panjang.

According to Suhaimi Kamaralzaman, the chief executive of Air Selangor, the water treatment plants need to be at a contamination level of 0TON (threshold order number) before it is safe for consumption.

“Currently the water contamination levels are at 1TON so it’s still not safe for consumption.

“It needs to be at 0TON and must produce the same results three times during testing before we are able to use the water,” said Suhaimi during a media briefing here. 

A total of 1,292 areas in the Klang Valley, Petaling, Klang/Shah Alam, Kuala Selangor, Hulu Selangor, Gombak and Kuala Langat have been experiencing unscheduled water supply disruption since 10am yesterday.

Water supply in the affected areas was disrupted following action to stop operations at the Sungai Selangor water treatment plants in Phases 1, 2 and 3, as well as Rantau Panjang due to pollution at the raw water source.

Suhaimi said the contamination levels were at 3TON at the time of discovery and confirmed that those responsible for the pollution are factories in the Sungai Gong industrial area. These factories are currently under investigation and earlier today, one factory was shut down by local authorities.

In order to clean the contaminated water, Air Selangor is pumping raw water from an alternative source called the Hybrid Off-River Augmentation System (Horas) 600 as well as releasing water from a nearby dam, which has a capacity of 500 million litres, to dilute the pollutants in the water.

Suhaimi said that once the water readings return to 0TON, they will continue pumping water into the contaminated water treatment plants for four days to make sure all pollutants are gone.

Only after these four days can the water be safely consumed, he said.

“The river has its own dilution factor so we have to wait for a 0TON reading three times consecutively before we can resume supply. We do this test three times in 30-minute intervals.

“I can’t give an exact date as to when things will be back to normal but we will be updating our progress three times a day on all our platforms,” said Suhaimi.

When asked if all consumers affected by the disruption will get water supply once the plants resume operations, Suhaimi said: “I answer that when we start pumping water.

“Then we will publish the schedule as to which area will get water on which day.

“At the moment, based on simulation, for something which has yet to happen, that’s our best prediction.”