The incident caused three of Pengurusan Air Selangor Sdn Bhd (Air Selangor) water treatment plants to be shut down on Friday (July 19).
Water, Land and Natural Resources Minister Dr Xavier Jayakumar said SPAN, as the regulatory body for the water supply and sewerage services, will conduct investigations according to the Water Services Industry Act 2006 (Act 655).
"The agencies under the ministry, namely SPAN, Irrigation and Drainage Department and Indah Water Konsortium, have been accelerating the recovery including identifying sources of the pollution through tests conducted in Batang Kali, Selangor on Saturday (July 20),” he said in a statement Sunday (July 21).
On Friday, Air Selangor had to shut down three major water treatment plants, namely the Sungai Selangor 1, 2 and 3 plants, as well as the Rantau Panjang water treatment plant to prevent polluted water from being processed and distributed to consumers.
Almost five million users around Selangor and Kuala Lumpur were affected by the water supply disruption.
Dr Xavier said that up to noon Sunday, the recovery work of the polluted sources had reached 94%, while the full recovery was expected on Wednesday (July 24).
He also urged all government agencies, especially the local authorities (PBTs) to carry out monitoring activities along the river banks.
"If the PBTs are more aware of any suspicious activity that has taken place in their area, such incidents of pollution can be avoided, and will certainly not burden the consumers like what happens now,” he said.
Dr Xavier also called for the PBTs to seize any premises suspected of contributing to the river pollution and take further action including legal action against the responsible parties.
He also suggested relevant agencies such as the Department of Environment under the Energy, Science and Technology, Environment and Climate Change (MESTECC) Ministry and other state government agencies to take proactive measures through continuous auditing activities and enforcement along the rivers nationwide.
"All parties and relevant agencies should play a role in preventing activities that could harm the river, which is the main raw water source of the country.
"The task of conserving water resources is not the duty of only one particular government agency,” he said. - Bernama