GEORGE TOWN: Low dissolved oxygen levels caused fish to die in Sungai Kulim here, says the state Environment Department (DOE).
“Based on the data observed by the automatic surveillance station in Sungai Kulim near the Kedah border, it was found that on the day of the incident, the dissolved oxygen content has decreased sharply, ” said its director Sharifah Zakiah Syed Sahab.
“The decrease occurs in parallel with the increase in the content of suspended solids, ” she added.
Sharifah added in a statement on Monday that the increase in suspended solids is likely due to heavy rainfall upstream, which increases surface runoff in the upstream area.
“The sudden decrease in oxygen is likely to have an impact on sensitive fish species, ” she said
Sharifah said that the Department collected water samples from Sungai Kulim following a report of dead fish, adding that local residents had reported the phenomenon of 'drunken fish' in Sungai Kulim near Kampung Tun Sardon, Ara Kuda, at 5.45pm on March 5.
“A team of Penang DOE officers started an investigation at the scene on the same day and found that there were dead fish floating on the river's surface, ” she said.
Sharifah added that water sampling was conducted at three locations in Sungai Kulim for analysis.
“Further investigations were carried out the next day to identify the potential causes of pollution in Sungai Kulim," she said.
Sharifah also said that a drone was used to monitor and survey the area and added that investigations along the upper part of Sungai Kulim from the location of the incident were carried out by heading down the river which enters the border of Kulim, Kedah.
“We found dead fish floating on the surface of Sungai Kulim near Lunas, Kulim," she said.
Sharifah said based on the investigation by the DOE branch in Kulim, there was no industrial source with the potential to pollute the river.
“Treated effluent discharge from the Kulim Industrial area is channeled to Sungai Seluang and its tributaries, to Sungai Jarak, and does not enter Sungai Kulim, ” she added.
She also said that the Penang DOE will continue to cooperate with the Kedah DOE in controlling cross-border pollution, adding that the incident would be reported to the Kedah Water Resources Board for appropriate action.
“Strict action will be taken against any party responsible for causing environmental pollution as stipulated under the Environmental Quality Act 1974.
The public can report pollution cases to the DOE at the toll-free line: 1-800-88-2727 or via an e-complaint at firstname.lastname@example.org.