The incident raised the ire of residents as water supply disruptions affected several parts of Johor Baru.

It also led to the state water utility company SAJ Ranhill Sdn Bhd to issue a notice saying that up to 1.8 million consumers could be affected by the incident.

However, what was troubling was that it was not the first time the same poultry farm contributed to ammonia pollution.

A previous case of ammonia pollution at Sungai Johor in July last year, which affected the water supply to 600,000 people, was partly caused by the same farm.

Johor Department of Environment (DoE) director Datuk Dr Mohammad Ezanni Mat Salleh said the poultry farm on the banks of Sungai Sayong, which is a tributary of Sungai Johor, was operating without the approval from the state DoE.

"The state DoE previously did not support the approval of the factory in the Preliminary Assessment Site (PAT) to proceed with the project in the area.

"However, it continued to operate. The farm operated under the jurisdiction of the Kulai District Land Office and Johor Veterinary Services Department, and these are the only agencies which can tell the farm to stop its operations," Dr Ezanni told the New Straits Times.

Dr Ezanni said that following the previous case of pollution that occurred in July last year, a meeting was conducted with all stakeholders and it was agreed upon that the factory should be relocated.

"However, there was no action taken on this, and the state DoE's notice to have the poultry farm relocated has fallen on deaf ears," said Dr Ezanni.

He said the department had no jurisdiction over this factory as it rears chicken and therefore any order to close must come from the Johor Veterinary Services Department or the District Land Office.

He said based on checks conducted by DoE staff at the farm since the previous case of pollution last year, the factory did not adhere to proper storage techniques for its fertiliser.

"The factory uses manure from the chicken to make fertiliser. Much of the fertiliser is improperly stored. The fertiliser products and chicken manure are stacked and exposed to the elements.

"When it rains, the water soaks these items and the water seeps into the ground and flows into the river. This leads to the high content of ammonia in the river," said Dr Ezanni.

Johor Health, Environment, Education and Information Committee chairman Datuk Ayub Rahmat confirmed that the ammonia pollution was caused by the premises which processed chicken manure.

Mr Ayub said this was the third incident of ammonia pollution and based on SAJ Ranhill's investigation, it was caused by the same party.

"The Department of Environment (DOE) previously did not support the approval in the PAT to proceed with the project in the area and we also regret that the local Land Office and Veterinary Department did not take stern action over the matter," he said.

Meanwhile, SAJ Ranhill's corporate communications head Jamaluddin Jamil said that two out of the three water treatment plants that were shut down had resumed operations.

"The Semanggar and Sungai Johor water treatment plants were re-opened about 7pm last night. Now, only the PUB (Public Utilities Board) Tai Hong water treatment plant remains closed," said Mr Jamaluddin. Regular water supply to several areas resumed Sunday night (29 October).