According to Penang DoE director Sharifah Zakiah Syed Sahab sedimentation caused by heavy rain had reduced the level of oxygen in the river.

She was responding to Penang executive councillor Norlela Ariffin’s complaint to the federal agency following the discovery of dead fishes at the river, which flows into her Penanti constituency. The villagers near the river called the incident “ikan mabuk” (drunken fish).

In a statement, Zakiah said the heavy rainfall recorded in the upstream section of the river, located in Kedah had likely caused the sedimentation in the river.

She added that the fishes had died near Lunas upstream of the river and later floated to the river’s banks in Penang.

“The sudden decrease in oxygen is likely to have impacted marine life in the river,” she said.

Zakiah also revealed that a joint Penang-Kedah DoE investigation over the weekend did not find any industrial discharge in the river as earlier suspected.

She said three areas of Sungai Kulim were sampled for analysis to study the cause of the dead fish phenomenon there, including a drone scan of the river to detect possible pollution causes.

Last month, a similar incident occurred where hundreds of dead fish were found on the banks of Sungai Perai, with the cause found to be untreated effluent discharged by a factory nearby.

The DoE had said a food processing factory by the river had released detergents directly into the river, causing the marine life in the area to die.

The factory was ordered to be closed for clean-up and was later fined RM18,000 under the Environmental Quality Act 1974.