Water supply back to normal.

The Cheras Batu 11 water treatment plant which was temporarily closed after  ammonia pollution in Sungai Langat resumed full operation at 8.30am yesterday, Syarikat Bekalan Air Selangor (Syabas) said.

Its corporate communications and public affairs assistant general manager, Priscilla Alfred, said consumers in the Hulu Langat area could expect their water supply to return to normal.

She said the Bukit Tampoi treatment plant, which supplies water to Kuala Langat residents, remained closed as the water being channelled from Sungai Langat still contained a high level of ammonia.

"The acceptable level of ammonia in the water is 1.5ppm.

"Currently, it is fluctuating between 3ppm and 5ppm.

"The Selangor Water Management Board (Luas) is doing all it can to reduce the level of ammonia."

Sungai Langat, which is the water source for the Cheras Batu 11 and Bukit Tampoi treatment plants, had seen an alarming spike in ammonia levels, forcing their closure since Thursday.

This had caused water supply disruptions in 36 areas under the Hulu Langat and Kuala Langat districts.

However, disruptions were minimal as Syabas was able to divert water from other places to sustain supply in the affected areas.

"The overall demand for water during this festive period dropped, hence, we were able to manage the disruption quite effectively."

As at noon yesterday, ammonia levels at the Bukit Tampoi treatment plant still showed a high reading of 5ppm.

Luas director Mohd Khairi Selamat said there were signs of reduction in the ammonia level.

He said he was optimistic that the plant could resume operations today if no additional effects were found.

Residents in the affected areas had expressed relief the water disruption was not severe enough to affect their Chinese New Year plans.