Its CEO Suhaimi Kamaralzaman said in a statement that operations at the four affected water treatment plants (WTP) would only restart when the odour pollution reading was at the zero threshold odour number (TON) three consecutive times.

“Air Selangor is taking this pollution issue seriously as it has caused operations to cease for over 24 hours and the recovery process is expected to take longer to ensure that all affected consumers will receive their water supply again,” he said.

He said, in the meantime, the number of public water tap locations had been increased for consumers to get alternative water supply.

Operations at the Rantau Panjang WTP and Sungai Selangor WTP phases 1, 2 and 3 were suspended yesterday morning after pollution was detected in the raw water.

A total of 1,292 locations across seven areas in the Klang Valley have been experiencing water supply disruptions since. The areas are Kuala Lumpur, Petaling, Klang/Shah Alam, Kuala Selangor, Hulu Selangor, Gombak and Kuala Langat.

Kajang assemblyman Hee Loy Sian revealed earlier today that the source of the pollution was a heavy vehicle workshop in Rawang. The pollutant was found to be diesel and the factory has since been sealed.

Meanwhile, Menteri Besar Amirudin Shari said efforts to eliminate the effects of the pollution had been under way since yesterday.

A total of 78 tankers, 22 jumbo lorry tanks, 54 static tanks, 18 local service centres and eight public water taps have been mobilised to help those affected.

Also, 23,000 five-litre bottles of drinking water have been distributed.