Singapore stopped water treatment operations at its waterworks in Johor on Thursday (April 4) due to high ammonia levels in the Johor River, The Straits Times reported.
The contamination happened after a reservoir of ammonia-contaminated water burst on April 3, polluting the the Sayong River, which flows into the Johor River, state news agency Bernama said.
The reservoir was located at a bio-composite centre next to an oil palm mill in Sedenak, the report added.
Ammonia has been used in water treatment systems to help detoxify drinking water. But in high concentrations, the corrosive substance can be toxic to humans, according to reports from the Water Quality Association and World Health Organisation.
Singapore’s Public Utilities Board (PUB) said the incident disrupted the water supply to the republic and some parts of Johor, but it had increased production at its other desalination plants and waterworks to compensate.
Malaysia also closed five water treatment plants as they could not cope with the river’s ammonia content, Bernama quoted Johor International Trade, Investment and Utility Committee chairman Jimmy Puah Wee Tse as saying.
The plants are the Sayong 1, Sayong 2, Semanggar, Sg Johor and Tai Hong water treatment plants.
Water supply was also cut off for some 17,000 residents in Kulai.
Puah added that the authorities had cancelled the refinery’s water abstraction licence and would fine the company.
Just last month, chemical dumping in Johor’s Kim Kim river caused almost 3,000 people in Pasir Gudang to suffer from gas poisoning.