Fort Canning Tunnel

The FCT cuts under Fort Canning Park and an access road, Canning Rise.[3][4] The entrance to the tunnel is roughly located on the land housing the Old National Library Building,[4][5] at the junction of Stamford Road, Armenian Street and Queen Street. It brings traffic to Penang Road, providing direct access to the Orchard area.[3][5] The stretch of Stamford Road between Queen Street and Bencoolen Street will also be permanently realigned in front of the National Museum of Singapore after the FCT's construction.[3] The bedrock of the area was the so-called Fort Canning Boulder Bed, a stiff clay with huge embedded boulders.[6]

The tunnel is part of a 500 m uni-directional three-lane new road. The FCT itself has a length of 350 m,[3] and will include an Electronic Road Pricing (ERP) gantry to "close up the Orchard Road ERP cordon".[5] The FCT incorporates electrical cables to ensure continued mobile phone and radio coverage. Furthermore, ventilation jets were installed in case of traffic congestion or fire.[5] The tunnel has no fire exits, due to the relatively short distance. National Fire Protection Association standards require emergency escapes in tunnels every 300 m. 4 closed-circuit TV cameras are installed, 2 of which are inside the tunnel.[7]

To make way for the construction process, the old National Library was demolished and moved to its present location along Victoria Street.[5] Sections of Canning Rise were closed twice during the course of construction. First, a stretch of road was closed for 3 months from 1 July 2004.[2] After this, a different section was closed "to facilitate the reinstatement works" of the FCT from 25 April 2006 for a period of two months.[10] However, this second closure was extended to 31 August.[11] In addition, a section of Stamford Road was temporarily redirected through the SMU campus near Prinsep Street during construction[4] before its final realignment in front of the National Museum.[3]

Their two bus stops were relocated. The diversion of Stamford Road had to put a bus stop near to the school (SMU), instead of near to National Museum of Singapore. This bus stop retains the CBD 1994-style bus stop pole look and the name was renamed from "National Library" to "Singapore History Museum", before changing it to "SMU". In 2002, the bus stop pole was expanded bigger.

In order not to conflict fast-moving traffic, the bus stop was moved to another side (Dhoby Ghaut MRT Station). It also retains the CBD 1994-style bus stop pole look.

180 m of the tunnel was constructed using an engineering technique known as the New Austrian Tunnelling method (NATM),[6] which is similar to mining.[5] The construction team used overlapping steel pipe roofs as support, with shotcrete lining, thick temporary invert, 2 layers of mesh, lattice girders and a watertight PVC membrane.[6] The FCT is the first Singaporean road tunnel to use NATM, which has saved at least 22 trees in Fort Canning Park,[12] including a 50-year-old tree.[5] None of the designated 'Heritage Trees' were impacted by the FCT project.[2] The remainder of the tunnel was constructed with the cheaper and more traditional cut-and-cover method.[6]

A professional arboriculture company, Arborculture, was employed to assess the risk to flora in the area, as well as provide conservation and management strategies.[13]