Tuen Mun Road is a major expressway which links the coastal city of Tuen Mun in the north west of Hong Kong’s New Territories to Tsuen Wan just north west of Kowloon. Built in 1977, the heavily trafficked road is part of Hong Kong's Route 9, which circumnavigates the New Territories and passes right through the centre of Tuen Mun.
An NEC-procured project to retrofit noise barriers along the town-centre section of the road is currently underway, aiming to reduce traffic noise being experienced by around 1800 homes by 1–25 dB(A).
The Highways Department of the Government of the Hong Kong Special Administrative Region let an NEC3 Engineering and Construction Contract Option A (priced contract with activity schedule) worth HK$585 million (£58 million) to a joint venture of Kwan On Construction Company Limited and China Geo-Engineering Corporation in late December 2015.
The work involves retrofitting 800 m of state-of-the-art noise barriers and enclosures, alongside and over live carriageways between Rose Dale Garden and Lakeshore Building, together with associated drainage, roadworks, utilities diversions, street lighting, traffic aids and landscaping works. Completion is scheduled for 2019.
NEC project manager is the Major Works Project Management Office of the Highways Department with Mannings (Asia) Consultants Limited as supervisor and designer.
PIONEERING TEAM SPIRIT
While NEC is now predominantly the default contract suite for new public works in Hong Kong, this project was selected as one of the pilot projects for adopting NEC. It was also the first ECC Option A contract to be used by the Highways Department.
Stephen Ko, senior engineer in the Major Works Project Management Office says, ‘The proactive mechanism in NEC to reduce the risk of going over budget and programme was the major reason for choosing NEC for this project. Also, the promotion of team spirit among all contracting parties would help to overcome potential problems on this busy and congested urban site.’ He adds that the employer, the contractor, the project manager and the supervisor have been fully committed to supporting the spirit of mutual trust and co-operation and to input all necessary resources to make it a success.
‘To streamline overall work processes, we also delegated adequate project manager powers to the supervisor for effective site management. This delegation arrangement streamlines procedures and, in most cases, means there is no need for the supervisor to seek further consents or approvals from us.’
A joint site office was set up to provide a smooth and effective communications between the parties. A ‘resolving problem first’ culture was also created and maintained, whereby when any of the parties is aware of any problem in relation to providing the works, the others collaborate promptly to find a solution.
Toby Ng, Mannings’ senior resident engineer, says, ‘We produce weekly NEC action lists, including the risk register and lists of project manager’s instructions, compensation events, notifications of compensation events and complaints. These are reviewed in weekly partnering workshops, which remind all parties to act properly and to complete their jobs in a timely fashion.’
So far Ng says 17 NEC risk reduction meetings have been held to discuss and resolve early warnings raised. ‘During the risk reduction meetings, all parties participate actively to find the most effective and economical solutions. Prompt actions taken after the meetings have resulted in most risks being reduced or eliminated, and more than 85% of NEC compensation events have been settled.’
A number of site problems were resolved under NEC processes. For example, an unexpectedly high rock strata was discovered during pre-drilling operation for friction-pile works. Subsequent to the early warning raised by the contractor, the supervisor changed to the rock-socketed pile foundation and revised the founding level to reduce the time needed for pile drilling and to minimise the risk of a failed casing retrieval. The revised foundation design was provided to the contractor in a timely manner, such that the piling works were completed with minimum disruption to overall progress.
A major constraint on construction work was that the existing number of traffic lanes through the works had to be maintained during the day time. During an early risk reduction meeting, the contractor proposed changing the pile-cap layout to allow temporary traffic diversions, which in turn would allow more work to be carried out during the day time. After review, the supervisor issued project manager instructions to change the pile-cap layouts as and when necessary.
When an uncharted water main chamber was discovered next to the proposed noise-barrier foundations, the contractor raised an early warning. The supervisor quickly changed the foundation design to avoid diversion of the water main and relocation of the chamber to minimise time and cost implications.
‘In the past 18 months, the project has faced a lot of challenges,’ says Ng. ‘Notwithstanding, with the spirit of mutual trust and co-operation established, all parties have attempted to resolve the challenges one by one.
‘Despite the extremely tight programme for completion of the works and site constraints, which range from existing utilities to live traffic flows, the project is running generally on time and on budget. All parties will continue to collaborate with each other to ensure a successful completion.’
BENEFITS OF USING NEC
- Technical matters can be resolved earlier under the established NEC mechanisms to minimise disruption to the works programme.
- Common goals among all parties can be achieved.
- Time and financial risk allocations are clearer to all parties, which are therefore more prepared to provide solutions for problems under their control.
Contact: Stephen Ko, Senior Engineer 2/Noise Mitigation, Major Works Project Management Office, Highways Department, The Government of the Hong Kong Special Administrative Region, Hong Kong
Tel: +852 2762 4140
Contact: Simon Ng, Director, Mannings (Asia) Consultants Limited, Hong Kong
Tel: + 852 3168 2028