To achieve Scotland’s target for generating 50% of all energy consumption from renewable sources by 2030, the country-wide electricity grid network requires updating.
This large-scale infrastructure project presents challenges to achieve the targets in a sustainable way while protecting sensitive species and habitats.
The Lairg-Loch Buidhe transmission reinforcement project encompassed the construction of a substation north of Lairg in addition to a new 132kV overhead line.
This connection is part of a wider aim to facilitate the increase in renewable energy generation and ensure security of electricity supply to the region.
With multiple protected areas - including moorland and peatland - in the vicinity of the proposed development, Ramboll ecologists were required to create novel assessment methods to identify the impacts that the project could have on sensitive species in the area.
Assessing wildlife impacts
The Ramboll ecology team identified five sites with a statutory designation for ornithological interest in the vicinity of the development, with one of the key species of interest being the protected black-throated diver.
Through baseline assessments, the team identified the construction of the proposed development as being a potential hazard to local protected bird species as a result of habitat, nest destruction and the disturbance of individuals.
Ornithologists at Ramboll, with experience working internationally on projects with potential impacts to protected bird species, were called on to identify possible impacts to the local bird population and create mitigation measures.
Innovative surveys
Ramboll was tasked with developing a method of assessing the impact of the proposed infrastructure on the protected black-throated diver.
By working collaboratively with NatureScot and a diver specialist, a novel collision-risk model was developed that could assess the risks.
This model was previously developed by the Ramboll ornithology team and adapted to create a robust assessment tool for this project.
Protection of birds
Line markers were installed along 4km of the overhead line to reduce the likelihood of bird collisions. This allowed for the development to proceed without a negative impact on the protected bird species.
Rafts were also incorporated into the development to create a positive impact on divers. These rafts are known to greatly improve the success of breeding birds, and the installation of a raft as part of the development has the potential to add another breeding pair of black-throated divers to the local population.
Conclusions
The collaboration between Ramboll specialists, NatureScot and diver specialists transformed this project to not only mitigate negative impacts on a protected bird species, but also to produce a net gain for biodiversity through the introduction of additional breeding areas for divers.