SMART Tunnel

The "Stormwater Management And Road Tunnel" or "SMART Tunnel", is a storm drainage and road structure in Kuala Lumpur, Malaysia, and a major national project in the country. The 9.7 km tunnel is the longest stormwater tunnel in South East Asia and second longest in Asia.

The main objective of this tunnel is to solve the problem of flash floods in Kuala Lumpur and also to reduce traffic jams along Jalan Sungai Besi and Loke Yew flyover at Pudu during rush hour. There are two components of this tunnel, the stormwater tunnel and motorway tunnel. It is the longest multi-purpose tunnel in the world.

In 2011, the SMART tunnel received the UN Habitat Scroll of Honour Award for its innovative and unique management of storm water and peak hour traffic.

It begins at Kampung Berembang lake near Klang River at Ampang and ends at Taman Desa lake near Kerayong River at Salak South. The project is led by the government, including Malaysian Highway Authority (Lembaga Lebuhraya Malaysia = LLM) and the Department of Irrigation and Drainage Malaysia (Jabatan Pengairan dan Saliran = JPS) and also a company joint venture pact between Gamuda Berhad and Malaysian Mining Corporation Berhad (MMC).

Route background
The Kilometre Zero of the tunnel starts at Salak Interchange.

History
In 2001 the Government sought proposals for a solution that would allow a typical flood of three to six hours’ duration to occur without flooding the city centre. A tunnel that would allow floods to bypass the centre was one way of achieving this, providing it was coupled with temporary storage facilities to keep flows downstream of Kuala Lumpur within the capacity of the river channel. A group led by Gamuda engaged SSP, a large Malaysian consultant engineering firm, and Mott MacDonald UK to develop proposals for a tunnel with holding ponds at upstream and downstream ends of the tunnel.

Construction of the tunnel began in 25 November 2003. Two Herrenknecht's Tunnel Boring Machines (TBM) from Germany were used, including "Tuah" on north side and "Gemilang" on south side. Gusztáv Klados was the senior project manager of the project.

On 11 December 2003, the 13.2 m diameter Mixshield TBM, Tuah, completed a 737 m section after 24 weeks of excavation. By the end of January 2004, Tuah would start a second drive covering a distance of 4.5 km to Kampung Berembang lake. The motorway sections on the SMART system was officially opened at 3:00PM, 14 May 2007, after multiple delays.

Meanwhile, the stormwater sections on the SMART system began operations at the end of January 2007.

As of July 18, 2010 the SMART system has prevented seven potentially disastrous flash floods in the city centre, having entered its first mode 3 operation only weeks after the opening of the motorway.

How the SMART Tunnel works
The first mode, under normal conditions where there is no storm, no flood water will be diverted into the system. When the second mode is activated, flood water is diverted into the bypass tunnel in the lower channel of the motorway tunnel. The motorway section is still open to traffic at this stage. When the third mode is in operation, the motorway will be closed to all traffic. After making sure all vehicles have exited the motorway, automated water-tight gates will be opened to allow flood waters to pass through. The motorway will be reopened to traffic within 48 hours of closure.

Stormwater tunnel

 * Construction cost: RM1,887 million (US$514.6 million)
 * Stormwater tunnel length: 9.7 km
 * Diameter: 13.2 m (43.3 ft) (outer diameter)
 * Tunnelling method: Tunnel Boring Machine (TBM)
 * TBM type: Slurry shield

Motorway tunnel

 * Motorway tunnel length: 4 km
 * Structure type: Double Deck
 * Ingress and egress: 1.5 km at Jalan Sultan Ismail and Jalan Imbi
 * Length: 1.4 km at Jalan Tun Razak
 * Links: 1.6 km at Kuala Lumpur-Seremban Expressway Links: City Centre near Kg. Pandan Roundabout KL-Seremban Expressway near Sungai Besi Airport

Features

 * Longest tunnel in Malaysia.
 * 9.7 km (6.03 miles) stormwater by-pass tunnel.
 * 4 km (2.49 miles) double-deck motorway within stormwater tunnel.
 * The motorway tunnel is suitable for light vehicles only. Motorcycles and heavy vehicles are not allowed.
 * Ingress and egress connections to the motorway tunnel linking the southern gateway to the city centre.
 * Holding basin complete with diversion and tunnel intake structures.
 * Storage reservoir and a twin-box culvert to release flood discharge.
 * State-of-the-art operations control room equipped with the latest systems in operations management, surveillance and maintenance of the SMART system.
 * Custom-made fire engine units consisting of two modified Toyota Hiluxes, parked at two different locations for quick access to the tunnel in case of fire on both carriageways.

Tunnel in popular culture

 * The SMART Tunnel was featured in an episode of Extreme Engineering on the Discovery Channel.
 * The SMART Tunnel was featured in an episode of Truly Malaysia on the National Geographic Channel and TV1.
 * The SMART Tunnel was featured in an episode of Man Made Marvels on the Science Channel.
 * The SMART Tunnel was featured in an episode of Megastructures on the National Geographic Channel and TV1.
 * The SMART Tunnel was featured in episode 2, Season 1, of Build It Bigger on the Science Channel.