Facilities modernisation on a UNESCO world heritage site.

Summary

As part of the extensive Air Ranges Modernisation programme, QinetiQ began work in 2017 to replace the 1970s-built infrastructure on St Kilda with environmentally-friendly accommodation, as well as a new Energy Centre to replace a noisy diesel-generated power station. However, a significant number of challenges had to be overcome to fulfil the programme.

The brief

The remote island of St Kilda, 40 miles west of the Outer Hebrides, has been home to MOD radar tracking equipment since 1957. This site plays a vital part in providing safe airspace for trials activity at the MOD Hebrides. It’s also home to rare birds and plants, a unique breed of sheep, and even its very own St Kilda mouse! Owned by National Trust Scotland, St Kilda is the only UK site designated twice by UNESCO as a World Heritage Site for both its natural and cultural heritage, so it was incumbent on us to ensure that we did nothing to impinge on the site’s heritage. It was also vitally important that the new infrastructure enhanced the existing site, was sympathetic and sustainable.

Our solution

Sympathetic design, development and build of new accommodation and energy centre. When excavation began in 2017, an archaeological dig found historical artefacts, from then on we ensured that we had a permanent onsite archaeologist with us wherever we excavated untouched ground. We also employed an independent environmental assessor to ensure compliance with the joint agreement held with the National Trust Scotland. As well as doing everything we could to avoid noise and disruption to the island’s wildlife, we also had to be vigilant with our Health & Safety policy to mitigate the extreme weather conditions. Bad weather also delayed boats bringing materials to and from the island, posing an added dimension to scheduling and delays; the team also needed to be exceptionally flexible to manage any unscheduled delays.

Outcomes and benefits

The new buildings are now not only aesthetically pleasing but also extremely energy efficient; they even have turf roofs! Clea Warner, the National Trust for Scotland’s General Manager North West and Islands, said: “We’ve been impressed by the way the MOD, QinetiQ and other partners have been determined to replace the facility with a structure that is informed by and complements St Kilda’s unrivalled setting. In the construction phase, every effort was made to avoid noise and disruption. The first results of this care and attention are almost magical. The moment the new power plant was switched on, the sounds of St Kilda reverted to only the waves and winds that the last inhabitants would have known so well.

“We’ve been impressed by the way all those involved have been determined to replace the facility with a structure that is informed by and complements St Kilda’s unrivalled setting.”