KUALA LUMPUR: An unexpected three-day water disruption in the Malaysian state of Selangor due to odour pollution, which left 1.5 million users in the lurch, might see a reprieve soon with one of the affected water plants back in service.
The Sungai Semenyih plant resumed operations at 1pm on Monday (Dec 23), the state’s water concessionaire Air Selangor said, while the Bukit Tampoi plant remained out of service.
Both plants were shut down at 7.15am on Saturday following detection of “solvent-like odour” in the Semenyih River, caused by dumping of industrial waste into manholes in Bandar Bukit Mahkota, Cheras.
“The treatment process and the production of treated water will take some time before water supply stabilises,” Air Selangor said in a statement.
To dilute the polluted Semenyih River, the Selangor Water Management Authority (LUAS) was pumping water from a lake into the river, it added.
“With this, we hope that the odour pollution does not return,” it said.
Air Selangor said in an earlier statement that 336,930 households were affected by this water cut.
Businessman Cheung Kwok Ying from Puchong said he had to stay at a budget hotel because he did not have enough time to store water at home.
“The water disruption is unbearable and expensive,” he told CNA.
The unscheduled water cut also caught many Chinese residents off guard as they were preparing to celebrate Winter Solstice, or Dong Zhi, on Sunday.
Mdm Soo Siew Lan said her family usually cooked up a feast for the occasion but could not do so without water supply.
“It was the saddest Winter Solstice celebration we’ve ever had,” the 70-year-old from Puchong said.
“Without water, I could not even make glutinous rice balls. That is our yearly tradition, one that I cherish doing with my three grandchildren.
“We just ate at a restaurant instead, like we would on a normal weekend,” she said.
Similarly, a woman, who only wanted to be known as Ms Stella, said her daycare centre in Bandar Puteri Puchong had to cancel the celebration and students were left disappointed.
She hoped the issue could be resolved soon.
ODOUR POLLUTION MEASURED IN TON
This was the second time in three months that the Sungai Semenyih water treatment plant was forced to close due to odour pollution.
On Sep 28, the plant halted operations for 10 hours due to unauthorised dumping of waste into the river.
In its statements, Air Selangor explained the odour pollution at the Semenyih River was measured at 2 TON on Saturday. Subsequently, the reading hovered between 1 TON and 2 TON.
“We would not be able to restart the operations at the Sungai Semenyih and Bukit Tampoi water treatment plants until the odour pollution stabilises at 0 TON,” it said on Monday.
TON is the abbreviation of Threshold Odour Number.
According to United Kingdom-based Water Research Center, the TON of pollutant in water can be determined by adding a volume of unpolluted water into a volume of polluted water, and then divide the total volume by the volume of polluted water.
The more water needed to make the odour undetectable, the higher the TON reading, it added.
“For a reading of 2 TON, an equal volume of unpolluted water needed to be added to polluted water, which means the pollution is serious,” it said on its website.
Following the detection of solvent odour at the Semenyih River, LUAS said authorities have ordered Indah Water Konsortium (IWK), a sewage treatment company, to immediately stop releasing water from its treatment plant into the river.
IWK had also agreed to permanently seal all 20 manholes in Bandar Bukit Mahkota to prevent illegal waste disposal from happening again.
EMERGENCY WATER SUPPLY PROVIDED
To assist affected residents, Air Selangor said it is providing emergency water supply through water tanks around the clock.
It has also activated service centres and public pipes, besides distributing bottled drinking water.
The Selangor Chief Minister’s Office decided in a meeting on Monday that water from Langat 2 water treatment plant, which is unaffected by the pollution, would be channelled into the Bangi water storage terminal.
“A total of 55,564 households will receive water supply from this measure,” he said.