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Tom Harris MP cuts the ribbon at the re-opening of the M25 Holmesdale Tunnel assisted by the Mayor of Enfield (right) and Ian Scholey of the Highways Agency (left).
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The facts
Client: Highways Agency
Location: London
Services: Highways, Structures, Civil
Engineering, Environmental, Geotechnical, Mechanical, Electrical,
Communications, CDM Co-ordinator, Road Safety Audits – Design and
Site Supervision
Sector: Highways
Contract Type: Highways Agency Early
Contractor Involvement – NEC Target Cost
Project Value: £75million
Start/Completion: August 2005 - December
2007
The project
The M25 Junction 25 Improvement and Holmesdale Tunnel
Refurbishment not only re-opened three months ahead of schedule,
but also achieved a significant Health & Safety landmark with
no accidents being reported in almost two million man
hours of work.
Considering that more than 120,000 vehicles a day use this
section of the M25 - making the Holmesdale Tunnel one of the
busiest stretches of motorway in Europe - this was a remarkable
achievement.
Designed by Capita Symonds on behalf of Costain, The Highways
Agency project was designed to reduce congestion and refurbish the
tunnel to address dilapidation and mitigate escalating maintenance
and operational risks. The improvement works involved adding an
additional eastbound lane through the junction and an additional
lane in each direction via the 650m tunnel.
The refurbishments included:
- replacement lighting
- new ventilation equipment
- internal cladding to provide passive fire protection
- tunnel control systems
- traffic monitoring and control systems
- emergency phones
- improvement of drainage
- removal of the raised walkways
- 20km of new ducting and
- 75km of new wiring
These improvements have led to the tunnel being one of the first
in the United Kingdom to meet the requirements of the European
Directive for Road Tunnel Safety
Awards
- Royal Society for the Prevention of Accidents – Gold Award
- Eurotest ‘Safest and Best Managed Roadworks Survey 2007’ – 1st
in UK, 2nd in Europe
- Highways Agency ‘World Class Safe Hours Worked’ Award