Providing the first direct route from the eastern New Territories to Hong Kong Island’s financial district is the Shatin to Central Link project.
More from: Going the distance: Hong Kong's MTR projects
MTR’s involvement in the construction of the high speed rail link to the mainland of China is overshadowing another mega-project.
The estimated HK$37.4bn (£3.1bn), 17km Shatin to Central Link project is in fact two projects in one and when complete will provide the first direct route from the New Territories to Hong Kong Island’s financial district.
The new line will also connect MTR’s East Rail Line, which runs from Kowloon to the Chinese border, to the West Rail Line.
This is the commuter link from Kowloon to the Northwestern New Territories. Part of the reason for building the new line is also to relieve congestion on the busy section between Shatin to Hung Hom of the East Rail Line.
The Kowloon section of the project involves chunks of drill and blast, bored tunnel and cut and cover as the line encounters the varied ground conditions.
The main part of the Shatin to Central Link project is known as the East-West Corridor. It will be a tunnelled metro line running from Tai Wai near the new town of Shatin to Hung Hom in southern Kowloon where track will link up with West Rail Line.
The second part of the project involves taking the line under Hong Kong Victoria Harbour from Hung Hom to Wan Chai North and Admiralty in the heart of Hong Kong Island’s financial and commercial district.
The project involves an array of tunnelling techniques and detailed design packages for this work are currently being let.
Halcrow has just won the design contract for the 2km drill and blast tunnel which takes the line under the Lion Rock. The consultant is also designing the parallel bored tunnels between the Lion Rock tunnel and the area south of Diamond Hill Station where the line passes beneath the Kwun Tong Line.
The Kowloon section of the project involves chunks of drill and blast, bored tunnel and cut and cover as the line encounters the varied ground conditions leading down to the harbour. Cut and cover tunnels will run across main roads and traffic will have to be diverted around the work sites, or put onto temporary platforms above them.
South of the existing Hung Hom terminus of the East Rail Line, the line will descend into a 1.5km immersed tube before passing through cut and cover and bored sections on Hong Kong Island, and ending in a drill and blast overrun south of the Admiralty Station terminus.
Station construction will also present major challenges.
South of the existing Hung Hom terminus, the line will descend into a 1.5km immersed tube before passing through cut and cover and bored sections.
Six of the 10 stations on the line are interchanges with existing or soon to be built lines. Some, like the Hung Hom terminusand the new terminus at Admiralty will need to conduct extensive underground work, while trains continue to run.
Hung Hom Station is a multistorey structure with underground platforms. Remodelling will result in East and West Rail Line tracks joining at new platforms to be built on the eastern edge of the station. Underneath these, MTR will thread new track feeding into the immersed tube tunnel under the harbour.
Admiralty Station is another key challenge, as the Shatin to Central Link will interchange with the Island Line, Tsuen Wan Line and the new South Island Line (East).
Here, platforms will be sited at the extension of the Admiralty Station under the Harcourt Garden with connections to the concourses and platforms of the Island Line and Tsuen Wan Line. Platforms will run on either side of those for the planned South Island Line (East).
Kwun Tong line extension
Also in the programme for completion by 2015 is the smaller Kwun Tong Line Extension, which connects the existing terminus Yau Ma Tei in central Kowloon with the densely populated residential area Whampoa Garden.
The 2.6km line crosses a densely populated area of Kowloon which is largely isolated from the subway system and will be built in tunnels using drill and blast methods.
The twin bore tunnel will narrow to a single bore near the terminus at Whampoa Garden which the two concourses will be a cut and cover structure.
Ho Man Tin Station is a new station and interchange all rolled into one. It will be sited 70m below the surface and built in an open cut with the Shatin to Central Link platforms running above and at right angles to platforms for the Kwun Tong Line Extension.
“Ho Man Tin Station is a challenge because of the multiple layers and the need to design to the satisfaction of the Fire Services Department,” says MTR Kwun Tong Line Extension design manager Lawrence Chung.
Design work is still underway at present.
South Island line (East)
The south side of Hong Kong Island is to get its first MTR subway line from 2015 when the South Island Line (East) is completed.
This 7km line runs from the existing Admiralty Station on the north side of the Hong Kong Island where it will interchange with the existing Tsuen Wan Line and Island Lines and the proposed Shatin to Central Link.
It will cut through the mountains in the middle of the Island in a 3km single bore drill and blast tunnel which joins 2km of viaduct. This will run all the way to the coast and across a narrow sea channel to Ap Lei Chau island. There the track descends into another drill and blast tunnel before reaching the cut and cover terminus at South Horizons.
The completed line is expected to cut journey times between South Horizons and Admiralty from up to an hour to about 10 minutes.
The new line has five new stations but they present some of the project’s biggest challenges. At Admiralty, the addition of the South Island Line (East) and the Shatin to Central Link platforms to the existing two-level interchange with the Island Line and the Tsuen Wan line will create MTR’s busiest interchange. Work involves extending the station to the east in an open cut box and excavating beneath the operational Island Line and Tsuen Wan Line.
The South Island Line team will carry out all the works for the station expansion at Admiralty including the Shatin to Central Link platforms.
Wong Chuk Hang station will be on a viaduct, with the foundations founded in the nullah, a flood relief channel. The potential impact of the viaduct piers and station foundations on water flow in the nullah has been carefully modelled to avoid flooding during the rainy season. “We have to maintain the existing hydraulic capacity so we will have to widen part of the nullah,” says MTR South Island Line (East) project manager Mark Cuzner.
Work in the nullah is not allowed during the rainy season between April and September, a factor which dictates the sequencing of the construction works. It is estimated that construction will start early next year.
Admiralty station Ove Arup & Partners
Tunnels Scott Wilson
Viaduct Atkins China
Depot Ove Arup & Partners
Hong Kong MTR projects: The Shatin to Central Link