Since yesterday morning, the taps have been running foul causing concern to thousands in Kuala Lumpur, Gombak, Petaling Jaya, Klang, Shah Alam, Kuala Selangor dan Kuala Langat.

The smell akin to that of excrement, led many to wonder if septic tanks had been damaged by the heavy downpour thus overflowing into the water catchment areas.

In a statement today, Syarikat Bekalan Air Selangor Sdn Bhd (Syabas) said the smell is caused by a chemical reaction.

According to a Bernama report, the company explained that the ammonia level in Sungai Selangor, from which the affected areas get their supply, had increased.

This was caused by river dams and ponds with dirty water overflowing into the river following the heavy downpour.

Syabas said three treatment plants were affected: Sungai Selangor Phase I and Phase III managed by Syarikat Pengeluar Air Sungai Selangor Sdn Bhd (Splash) and Phase II managed by Puncak Niaga (M) Sdn Bhd.

Back to normal

The company said the immediate action of the treatment plant officials was to add the chlorine level in order to reduce the ammonia content in the untreated water.

The chemical reaction had caused the water to smell, it added.

Syabas had already informed the Selangor government and asked it to conduct a study and monitor the Sungai Selangor area.

The company also advised consumers not to be alarmed as tests have shown that the treated water is safe for consumption.

Subsequent checks, it said, had revealed that the ammonia level in the water source had returned to normal and the supplied water will return to normal over the next day or two.

The heavy downpour over the weekend had wreaked havoc on several parts of Selangor and the city.

The affected areas were Taman Tun Dr Ismail Jaya, New Klang Valley Expressway at Bukit Jelutong, Kampung Landasan at Kampung Melayu Subang, the areas around Giant Hypermarket at Section 13, Kampung Kebun Bunga Batu Tiga and areas surrounding Makro supermarket.

More than 9,000 people were evacuated, over 3,000 houses were damaged and about 1,000 vehicles were submerged in the floods.