A LANDSLIDE upstream of Sungai Kerling, a river flowing from the Gading Forest Reserve in Hulu Selangor, may have caused the water in Sungai Selangor to turn muddy, said Selangor Water Management Authority (Luas).
Initial findings found that a water surge had occurred in the Sungai Kerling channel and the muddy flow had travelled 37.4km along the tributary into Sungai Selangor.
Luas was alerted to the sudden and heavy flow of mud-coloured water at 10.30am on Saturday (Aug 12) where initial site investigations had found high turbidity levels of up to 6,000 NTU.
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Under the Drinking Water Quality Standard by the Health Ministry, the acceptable turbidity level of raw water is 1,000 NTU. For drinking water, the maximum accepted level is 5 NTU.
“Following this discovery, 900 MLD (millions of litres per day) of raw water was released from Horas 600, an off-river storage facility located at Kampung Sungai Darah, Bestari Jaya, Kuala Selangor for dilution purposes. At the same time two barrage gates were opened to hasten the discharge of muddy flow to the downstream of Sungai Selangor,” said Luas.
As of 5.55pm on Saturday, the turbidity level in Sungai Selangor had receded to 1,000 NTU. Luas has assured that on-site monitoring will be carried out until water turbidity in Sungai Selangor is restored to normal levels.