Odour pollution that caused the Rantau Panjang water treatment plant to shut down for several hours yesterday may have been caused by residual pollutants from a previous incident, said the Selangor Water Management Board (Luas).
“A comprehensive investigations found that the odour pollution is believed to have been due to residual smells found on the riverbanks, or perhaps sediments around the (water treatment plant’s) inlets following the previous odour pollution incident and the high river water levels last night,” it said.
The plant was shut down at 7.10pm yesterday after odour pollution measuring one TON (threshold odour number) was detected at Sungai Sembah and the Rantau Panjang water treatment plant’s inlet ten minutes earlier.
The same plant had just recovered from an odour pollution incident last week where a factory is believed to have illegally discharged chemical wastes, which in turn caused water supply disruptions for Klang Valley residents.
In response, Luas said it had activated pumps and opened a barrage door the Bestari Jaya alternative pond to flush the pollutants downstream.
It said the large volume of water flowing through Sungai Selangor at 9pm yesterday also aided the flushing, at a rate of 12.77 billion litres per day.
“The mitigation measures successfully curbed the pollution and the Rantau Panjang water treatment plant could resume operations in less than three hours, which was at 9.30 last night,” it said.