16 July 2010
The £93m M25 Bell Common Tunnel
refurbishment project has won the ‘Physical Achievement >
£2.5m’ category at the ICE’s East of England Merit
Bell Common Tunnel, team left to right: Carl Scrymgeour, Andrew
Firth, John Buckley
Following the success of the
M25 Holmesdale Tunnel Refurbishment, a
multidisciplinary Capita Symonds team was appointed as Costain’s
designer for the Highways Agency Early Contractor Involvement
scheme in 2008.
The project opened two months early, under
budget, and with an excellent safety record.
Originally opened in 1984 as part of the M25
North Orbital Motorway, the Tunnel is approximately 500 metres long
and located in a semi rural location in Epping Forest with a
cricket pitch on the roof.
The scheme included the removal of raised
walkways to meet disability access requirements, improve access for
emergency services and the facilitating of carriageway widening
works. The ventilation was also brought up to current
European standards by the construction of a Saccardo nozzle fan
system located at the tunnel portals to control pollution and smoke
in the event of a fire.
The tunnel has a dimmable lighting system to
reduce energy consumption while other works included installation
of passive fire protection and provision of an Automatic Video
Incident Detection system.
A Capita Symonds design team mainly from the
East Grinstead office undertook all the design work, working
closely with Costain and a number of key suppliers. There were a
number of environmental issues concerning ecological management in
the adjacent Epping Forest which have been solved thanks to
extensive liaison with the Corporation of London.