Construction of nine kilometres of dual carriageway between Kincraig and Dalraddy in a restricted working environment and within the confines of the Cairngorms National Park, a site of special scientific interest.
Project Overview
Design and build of 7.5km of online single carriageway, with an average annual daily traffic count of 5,500, to dual carriageway standard, together with the construction of approximately 1.8km of existing wide single 2+1 (WS2+1) carriageway to single carriageway. The project also included the construction of several structures, requiring extensive temporary works and traffic management phasing.
The project was delivered in a live restrictive operational area that required extensive temporary traffic management (TTM) planning to allow the works to be undertaken safely, whilst always maintaining traffic in both directions including CFA piling, soil nailing and “Teretrel” reinforced earth system. Significant vehicular and pedestrian TTM plans were designed and implemented in accordance with Chapter 8 and all TTM was incorporated into the build sequence due to the road needing to remain open with no diversion route available.
Extensive environmental constraints and advanced ecological surveys were undertaken prior to the works commencing with the project running through Cairngorms National Park adjacent to a Natura 2000 area. This included the relocation of 150 Hairy Wood Ants, which are named on the Scottish Biodiversity List as a species of high importance to biodiversity conservation.
Due to the project remoteness in the Scottish Highlands, a bituminous and concrete onsite batching plant was mobilised in a disused mothballed quarry 5km east of the project. Both plants were fully accredited, Sector Scheme approved, and the on-site laboratory was UKAS Accredited.
The project was awarded the “Performance beyond Compliance” rating for its Considerate Constructors public responsibilities, and its exceptional efforts made in managing the stakeholders and minimising disruption to the travelling public.
The project required extensive consultation and liaison with over 42 tenants, several local businesses, Cairngorms National Park, and a local school.
Key Features
- Major earthworks - 385,000m³ of cut and 250,000m³ of Class 1 embankment fill
- 8.9km of temporary haul road construction
- 114,000m² full depth carriageway reconstruction utilising a flexible composite pavement design
- Peat excavation and the use of deposition and peat restoration areas
- 13,284m of permanent filter drainage and 9,523m of temporary earthworks drainage
- Three pre-cast and in-situ concrete vehicular underpasses
- Two road bridges over Salmonid watercourses
- 7.5km of pedestrian footpaths and cycleways
- Hard and soft landscaping works, including top soiling, grassing of landscaped areas, tree and hedge planting
- Environmental mitigation works, including the construction of temporary fish ladders and otter protection measures
Project Team
Client:Transport Scotland
Project Details
Contract Value:€40.0 Million
Floor Area:
7.45km Dual Carriageway
Duration:
27 Months
Location:
Scotland