In a statement, Syabas said raw water from Sungai Kembong in Selangor was contaminated due to "leachate" leaking from a breached dyke in the landfill.
"The plant was closed immediately upon detecting high content of ammonia in the water at 6.41mg per litre, which is above the health safety standard of 1.5mg per litre, put into place by the Health Ministry.
"A yellow alert emergency plan has been into place. We are now trying to redistribute water from other treatment plants to the affected areas," it said.
The closure of the plant, which treated some 600mil litres of water daily, is expected to affect supply to 1.2mil residents or 300,000 households in four areas - Petaling, Hulu Langat, Sepang and Kuala Langat.
Leachate = usually refers to the liquid that drains out the bottom of landfills, garbage dumps, or other waste disposal sites. Leachate forms as water percolates through solid waste.
Abstracted from TheStarOnline