New water detention tank by 2025 to prevent flooding in Jalan Besar

The tank is designed to cut off the water flow from Rochor Canal into the drains along Syed Alwi Road.
The tank is designed to cut off the water flow from Rochor Canal into the drains along Syed Alwi Road.PHOTO: LIANHE ZAOBAO

A new underground detention tank will be built beside Syed Alwi Road by 2025 to prevent flooding in the low-lying Jalan Besar area.

Construction of the tank, due to begin in the third quarter of this year, is part of Singapore's wider efforts to adapt to climate change, which will bring about more frequent and intense rainstorms.

When completed, it will be able to hold about 9,300 cubic m of water, or approximately the capacity of four Olympic-size pools.

A pumping facility will accompany the tank.

National water agency PUB said yesterday that the tank is designed to cut off the water flow from Rochor Canal into the drains along Syed Alwi Road.

It will also temporarily store storm water that falls over the catchment area. During and after storms, the water will be pumped out of the tank and back into the canal.

PUB has previously made efforts to combat flooding in the area.

In 2015, Rochor Canal, which runs along Sungei Road and Rochor Canal Road, was widened and deepened to improve its capacity.

Other measures to reduce flood risks - such as raising the buildings and roads in the area - are not possible as many parts of Jalan Besar have been gazetted as conservation areas, said a PUB spokesman.

Jalan Besar GRC MP Denise Phua told Chinese daily Lianhe Zaobao that there has been no significant feedback on flash floods in the Jalan Besar area since the upgrades in 2015. Areas that had been more prone to flooding in the past included Syed Alwi Road, Kitchener Road, Jalan Berseh and Kelantan Lane, she said.

Ms Phua also said the upcoming Syed Alwi Detention Tank is a result of PUB's proactiveness to further enhance flood protection.

Plans for its construction were first announced last year by then Minister for the Environment and Water Resources Masagos Zulkifli.

There are two other previously constructed tanks: the Stamford Detention Tank in Tanglin with a capacity of 38,000 cubic m, and one in Opera Estate near Bedok with a capacity of 15,000 cubic m.

Associate Professor Vladan Babovic from the National University of Singapore's Department of Civil and Environmental Engineering said that constructing water detention tanks underground is an intelligent use of space in land-scarce Singapore.

"As more intensive rainfall is expected in the coming years and decades, and as the city grows and gets more densely populated, it is necessary to take advantage of subterranean spaces," said Prof Babovic, who specialises in hydroinformatics - the use of advanced technology in managing water resources.

A version of this article appeared in the print edition of The Straits Times on January 26, 2021, with the headline 'New water detention tank by 2025 to prevent flooding in Jalan Besar'. Subscribe