Relocation of ventilation building of Central-Wan Chai Bypass not feasible (with photo)

     On suggestions by a concern group to relocate the west ventilation building (WVB) of the Central-Wan Chai Bypass project (CWB), a spokesman for the Transport and Housing Bureau said today (September 15) that the Administration had given due consideration to the proposal and considered it not feasible due to safety consideration and technical constraints; and serious implication on the completion time of the project.

     "The Administration's proposed location of the WVB is directly above the CWB tunnel portal in Central, while the proposed location by the concern group is 300 metres west of the tunnel portal."

     "The proposed location is not viable because for considerations of fire and operational safety, designated electrical and mechanical (E&M) facilities must be housed above ground."

     "The usable area of the proposed site at the ground level (around 680 square metres) is not adequate to accommodate the plants for the operation of the CWB tunnel which are required to be housed above ground for fire and operational safety reasons," the spokesman said.

     "Besides, if the WVB is relocated to the site proposed by the concern group, substantial length of ventilation tunnel and electrical and mechanical cable tunnel will be required to link the CWB tunnel with the ventilation building."

     "Given the location of the existing underground structures at the proposed site, including MTR Hong Kong Station's cooling water facility and the foundations of an existing footbridge linking the International Finance Centre to the Central Ferry Piers, the required ventilation and E&M cable tunnels must be constructed deep below the ground (about 30 metres) within very confined space instead of 13.6 metres as suggested.  The limitation of underground space poses a severe constraint on the construction of these tunnels and very high risks to the safety of the construction workers as well as road users," he added.

     "During the construction period, it will necessitate more extensive road works and traffic diversion in the busy part of Central when compared to the Administration's option, which will further worsen the traffic in Central."

     The spokesman explained that the increase in the length of ventilation tunnel and other associated electrical and mechanical works would mean additional power consumption and increase in the size and bulk of the ventilation building, resulting in more impact on the environment and higher noise levels during operation.

     "Given the substantial length of the ventilation tunnel and electrical and mechanical tunnel required in the proposed alternative site, as well as the complexity of the works involved there, the proposed relocation is estimated to incur substantial construction cost of as much as $1.8 billion".

     The spokesman also clarified that relocating the ventilation building at this stage will not only require re-design but also re-gazettal and environmental impact assessment for the new site.

     "Since the construction works of the CWB are now in full swing, such changes at this stage will delay the commissioning of the road project by at least two years," he said.

     The CWB project (including the current location of the WVB) has already gone through extensive consultation and relevant statutory process.  The location, footprint and maximum height of the WVB were clearly shown on the plan of the CWB project as gazetted under Roads (Works, Use and Compensation) Ordinance in 2007.  And having regard to the considerations of land use, environmental impacts and minimum disruption to the public, the Administration's proposed location is the most suitable one.  The project was duly authorised by the Chief Executive in Council in May 2009.
     "It is in the interest of the public at large to see the earliest implementation of the CWB project to allow improvement to the traffic situation along Connaught Road and Gloucester Road soonest possible.  Thus, the Administration is committed to taking forward this project as quickly as possible."

     In implementing the project, the Administration will implement all necessary mitigation measures as set out in the Environmental Impact Assessment (EIA) report to address the public concern on the air quality and noise impacts, as well as the visual impact.  A photomontage showing the impression of the future development in New Central Harbourfront with the WVB is attached.

     The environmental aspects and visual impacts of the WVB have been fully assessed in accordance with the EIA Ordinance.  The Administration will adopt the means approved in the EIA report, such as minimising the building height of WVB; and actively plan for the trial  of a state-of-the-art air purification system in the tunnel ventilation system to alleviate public concern and to keep the impact to an acceptable level.

Ends/Wednesday, September 15, 2010
Issued at HKT 21:24