PETALING JAYA: Taps in 36 housing areas in Kuala Langat and Hulu Langat continued to stay dry as the two water treatment plants supplying them had to be shut down due to worsening ammonia pollution in the Langat river.
According to the Selangor Water Management Authority (LUAS), initial ammonia levels in the river went up in late January, forcing the Batu 11, Cheras and Bukit Tampoi plants to stop operating.
They have remained closed, with LUAS director Md Khairi Selamat adding that the ammonia could have been diluted to safer levels if not for the recent dry spell, especially around the Langat catchment.
“This has caused increased concentration of ammonia in the river,” said Khairi, adding that the Batu 11 and Bukit Tampoi plants were closed on Jan 28 and 29 respectively.
Both were found to have had ammonia readings beyond the threshold level, where end users can detect the smell, which is 1.5ppm (parts per million).
This, he added, led the National Water Services Commission (SPAN) to direct Indah Water Konsortium to directly operate sewage treatment plants that are discharging treated wastewater into the Langat catchment.
These include taking control of a sewage treatment plant operated by a Federal Reserve Unit camp which was found to have discharged high levels of ammonia into the river.
Despite these moves, the ammonia levels in the river could not reach satisfactory levels, at least not for sustained periods.
On Feb 2, the Batu 11 plant resumed operations for a while after water was released from the Langat Dam to dilute the river pollutants. It was closed again on Feb 4, and reopened on Feb 7 after rain in the catchment the night before.
Syarikat Bekalan Air Selangor corporate communications deputy general manager Priscilla Alfred said the plants were still closed as at yesterday.