Areas affected by Monday's flood not within Smart tunnel coverage

 

The Stormwater Management and Road Tunnel (Smart) tunnel could not assist in the flash floods that badly hit Klang Valley as it was not located within the flood alleviation system’s coverage area.

However, Syarikat Mengurus Air Banjir dan Terowong Sdn Bhd said that the tunnel managed to divert over one million cubic metres of floodwaters that day, utilising a third of the overall capacity of its four-mode system.

“This was because the catchments it serves experienced relatively lesser rainfall intensity compared to the other areas in Kuala Lumpur that were hit by the flash floods.

“In contrast, the Smart tunnel had to utilise 100 percent of its capacity in diverting floodwaters in the floods of December 2021 because the rain intensity patterns then affected different areas, in particular, the Sungai Klang and Sungai Ampang upstream catchments,” it said in a statement.

The Smart tunnel is capable of storing three million cubic metres of floodwater at any time.

On Monday (March 7), flash floods struck the Klang Valley, badly affecting Jalan Kuchai Lama and Jalan Klang Lama and the carrying capacity of Sungai Kerayong, Sungai Bunus and Sungai Kuyoh.

Environment and Water minister Tuan Ibrahim Tuan Man described the rainfall as “half a month’s average rainfall in two hours”.

Monday’s rainfall triggered Mode 3 of the tunnel at 4.40pm that day, clearing the tunnel’s motorway component in preparation for full closure.

However, by 8pm the tunnel was reopened without the need for Mode 4 to be activated.

Syarikat Mengurus Air Banjir dan Terowong Sdn Bhd called for flood mitigation solutions in the northwestern side of Kuala Lumpur, particularly in Sungai Gombak and Sungai Bunus.

“Given the advent of climate change which is now upon us, increased frequency of extreme weather events is forthcoming and given this, a holistic flood mitigation solution particularly targeting the northwestern side of Kuala Lumpur within the catchments of Sungai Gombak and Sungai Bunus will need to be expedited on top of a robust maintenance regime for our local drainage networks to minimise the future impact of these extreme weather events in Kuala Lumpur,” it said.

During the December 2021 floods, the Smart tunnel was activated for 22 hours, diverting the rising waters of the Klang River.

It set a record in water diversion by diverting five million cubic metres of water. - Mkini