The MTR Corporation recently completed a detailed review into the progress of construction on the South Island (East) (“SIL(E)”) and Kwun Tong Line Extension (“KTE”) projects and has shared the results of that review in a submission to the Legislative Council Panel on Transport Subcommittee on Matters Relating to Railways.
Overall works on SIL(E) and KTE projects are now over 70 and 60 percent complete respectively. This is not as far advanced as they should have been at this point in time as construction programmes have been impacted by the complexity of the construction methods required, tight space constraints in the highly-develop areas and the importance of maintaining safety for nearby communities and construction staff on site.
At present both SIL(E) and KTE projects are about six months behind schedule. Current estimates are that the original targets for opening SIL(E) and KTE in 2015 cannot be achieved.
“I am sorry to disappoint the communities and make them wait longer for railway service at their doorstep,” said Mr Jay Walder, Chief Executive Officer of MTR Corporation.
“We know the communities in Southern District, Ho Man Tin and Hung Hom have been looking forward to the early enjoyment of convenient rail transport. Significant progress has been made and the project teams have been making every effort to overcome the challenges they have been presented with to try and meet the original opening targets,” said Mr Jay Walder. “However, due to the difficult circumstances, particularly at Admiralty Station for SIL(E) and Whampoa Station for KTE, we have to let the community know that the target opening dates for the two new railways will have to be revised.”
The Corporation will continue to strive to complete the projects as soon as possible. Another progress update will be provided at the end of this year when more certainty on the timeframes for the opening arrangements of the two new lines should be available.
“Understanding the community’s desire to be provided with more information on the progress of the various railway projects, we have committed to carry out our construction programmes with greater openness and transparency,” said Mr Walder. “We will continue to provide regular reports to the Government, the Legislative Council and the community through various channels. In spite of the challenges experienced in the different projects, the Corporation will continue to work hard to overcome these challenges to deliver railway services to the various communities as early as possible.”
South Island Line (East)
Up to May 2014, over 70% of the works for SIL(E) has been completed. This includes 90% completion of the viaduct works and 87% of the drill and blast excavation works for the Nam Fung Tunnel section. Excavation of the main tunnel at Ap Lei Chau has been completed.
For the Nam Fung section, difficult and unstable ground conditions including two major fault zones along the tunnel alignment have dictated slow progress. Tunnelling works have now safely passed through the difficult ground and tunnel blasting works are targeted for completion in the third quarter of 2014. Tunnel lining works and the construction of the transition structure that connects the tunnel section to the viaduct section are in progress and expected to be completed in the fourth quarter of 2014. Structural works for the Nam Fung Ventilation Building are also in progress and expected to be completed at the end of 2014.
The project, however, is being seriously challenged by the complexity of construction works at Admiralty Station, which has led to the overall programme falling behind by approximately six months, hence rendering the scheduled opening of the line in 2015 unachievable.
In future, the extended Admiralty Station will be a mega interchange station, with six underground levels, serving four railway lines including two existing lines – Island Line and Tsuen Wan Line – and two new lines – SIL(E) and Shatin to Central Link. The extension works of the station are being carried out under Harcourt Garden, east of Admiralty Station, with three additional levels being constructed below the level of the existing station. Currently the excavation at the Harcourt Garden works site has reached the fourth and fifth levels of the extended Admiralty Station.
The most complex part of the extension works is the excavation of the ground under the existing railway lines. The method calls for the underpinning of the running line tunnels, whereby they are supported by a series of hydraulic jacks with the load of the existing rail tunnel being methodically transferred from one set of jacks to another as excavation is conducted layer by layer.
In conducting the underpinning structural works below the existing railways lines at Admiralty Station, safety of the passengers using the existing railway and occupants in the surrounding buildings continues to be the number one priority. Strict engineering control of the works is maintained with the safety of the railway structures as the primary objective. Works are only allowed to move to the next stage after they have been carefully inspected and confirmed as satisfactory. The resulting progress rate has limited the ability to catch up when more than expected difficulties are encountered in the underpinning work.
Kwun Tong Line Extension
As at the end of May 2014, the KTE project is over 60% complete. This includes completion of the site formation excavation of Ho Man Tin Station and 92% completion of the excavation for the tunnel section between Yau Ma Tei and Whampoa.
The most challenging part of the project is works at the Whampoa Station site where extensive excavation works are being carried out within a densely populated community with busy traffic and complex underground utilities. The implementation of protection works for underground utilities and limited working space have prolonged the process during the early stage of construction.
To minimise impact on residents and traffic and to make room from traffic lanes and footpaths for construction works, more than 100 stages of Temporary Traffic Management Scheme (“TTMS”) were required to complete the cofferdam piling and utility works.
As a result of the difficulties at Whampoa Station, construction progress is approximately six months behind schedule.