SMART solution for storm water

SMART solution for storm water

To counteract Kuala Lumpur’s notorious flash flooding problem, the Malaysian government introduced the SMART (Storm Water Management and Road Tunnel) project. This ingenious flood control measure uses a diversion tunnel for storm water, which doubles as a motorway link during the drier periods. 76 Flygt pumps from Xylem were chosen for this ambitious project.

Located at the confluence of the Klang and Gombak rivers, the area around Kuala Lumpur is prone to serious flooding. As the city continues to develop, this has placed additional pressure on its drainage system’s ability to cope with flash floods. Between 2000 and 2003, the city experienced devastating floodwater damage.

In 2004, the SMART project was initiated as a solution to control storm water. Kuala Lumpur would divert storm water before it entered the city center by constructing a 9.7-kilometer long tunnel, which could hold up to 1.0 million cubic-meters of water. The water could then be released into the river downstream from the city to prevent flooding.

One of the most innovative features of the tunnel was that it included a three-kilometer “double-decker” motorway. During drier periods vehicles could use the SMART tunnel motorway, thus relieving traffic on the city’s main highways.

This US$ 600-million project included several elements: a holding basin with a floodwater storage capacity of 600,000 cubic meters, a reservoir with a capacity of 1.4 million cubic meters, and the bypass tunnel. It also involved a control center for managing, operating and maintaining the SMART system.

Flygt pumps dewater the tunnel

To handle such large volumes of water in extreme storms, pumps had a huge role to play – as in any project involving floodwater control. 23 pump stations were installed equipped with high-tech pumping solutions, capable of dewatering all floodwater in the tunnel within 24 hours. After evaluating a vast array of pump offers from different manufacturers, 76 Flygt pumps were chosen due to their superior performance and quality, even though they were slightly more expensive than rival offerings.

“Flygt has a proven track record, with many successful installations in irrigation and flood control applications,” says Koon Sing Low, Director of SMART. “That, combined with their competent technical support and after sales service, and our close relationship via frequent in-house trainings and seminars, is why we chose them for this project.”

The main pumps were to be installed right next to the tunnel gate, where strong turbulent flow was expected as the floodwater hit against the tunnel gate, so the strength and efficiency of these pumps was crucial.

Special concrete walls and inlet openings were designed with the help of Xylem technical support to protect the four CP3800/865/375 kw pumps. Meanwhile, five CT3501/835/170 kw suction inlet pumps were installed in the long tunnel to dry the installed pumps.

Before starting the project, Xylem did several calculations to minimize power requirements. “We were told that our client was able to downsize the generator setup by 1000 KVA with our assistance,” says William Choong, Transport Business Unit Manager in Malaysia who was involved in the SMART contract.

Award-winning solution inspires others

The SMART project was successfully tested and commissioned in late 2007, and to date has prevented the city of Kuala Lumpur from further serious flooding.

So ingenious was the project from an innovation, functionality and affordability perspective that it received much media coverage and several international engineering awards. The National Geographic Channel dedicated an episode of its “Megastructures” series to the SMART system.

“The key to success was careful planning, design and implementation, plus selecting the best construction method and equipment which also come with local expertise support,” says SMART Director Koon Sing Low.

Other cities that face similar flooding issues such as Singapore and Jakarta have also visited the SMART tunnel to investigate a similar project back home.

“Since the success of the SMART project, we’ve received many orders from other flood mitigation projects across Malaysia,” concludes Choong. “This has confirmed our position as the market leader in flood mitigation projects.”

Project specifications

76 Flygt pumps were used for the SMART project:

Portal: 18 x N/CP 3201MT c/w fluid valve, 3 x CP3306 c/w flush valve, 2 x CP3102 HT

Cross passage: 18 x NP3153SH. 9 x CP3102HT

Shaft drainage: 8 x CP3152HT

Main road tunnel: 5 x CT 3501/835/170kw, 2 x CT3300MT, 2 x CP3085MT

Main flood tunnel: 4 x CP3800/905/275kw, 1 x CP3300MT

Fire pumps: 1 x A. G. c/w 110kw engine, 1 x A.G.  c/w 110kw  motor, 1 x  CP3085HT

1 x Lowara multistage 11kw.

by Alannah Eames