Olympic Powerlines Project

Scope of works

The £250m powerlines project saw the construction of two 6-kilometre tunnels beneath the Olympic Park and Lower Lea Valley region, enabling the power needed for the London 2012 Olympic Games and legacy developments to be carried out underground.

The construction of the underground tunnels allowed 52 overhead electricity pylons to be removed from the Olympic Park skyline, unlocking the landscape for the construction of venues and infrastructure. Kilnbridge carried out the following works on the project:

• The installation of the fire wall using the British Gypsum shaft wall system and Glasroc S Passive Fire Board System on the steel columns interface
• Intumescent detailing on the rockwool at the top of shaft wall and all interfaces sealed with intumescent mastic against cold smoke
• The installation of 4-hour fire rated intucompound, load bearing fire and smoke seals to all ducts from tunnel level to ground level at all head house locations
• The removal of the existing fire penetration seal above the door heads and at the gap between the door jamb and concrete interface. Once removed, angle framework and a durasteel blast board were installed, including cutting and scribing services
• Covering all interfaces with a mastic joint of silicon intumescent to allow for movement
• Fire stopping to penetrations through blockwork, dry lining and concrete floor slabs and riser infills

Challenges / Achievements

• In 2009, the Olympic Park Powerlines Project was awarded the Project of the Year Award by the Association for Project Management, who called it a “ground-breaking project” in recognition of the highly complex and challenging powerlines work being delivered to an unprecedented timetable and within budget