Case study

Coire Glas hydro pumped storage scheme ground investigation

Scottish Highlands

Content from the Coire Glas hydro pumped storage scheme in Scotland, UK as part of a Ground Investigation project for LSC.


SSE Renewables

Project Duration

April - December2023 (Reporting will go on through to July 2024)

We undertook an intricate and comprehensive ground investigation for a ground-breaking hydro pumped storage project being developed by SSE Renewables at Coire Glas in the Scottish Highlands. The first large scale pumped storage project to be developed in the UK for more than four decades, this project holds significant importance in advancing the UK's efforts toward achieving net-zero emissions while concurrently ensuring the stability and security of the nation’s power supply.

Planning, feasibility, conceptual design



Operations and maintenance


Show full process

Situated in the remote and challenging terrain of the Scottish Highlands, the Coire Glas site posed unique difficulties with its high elevation, sloping and uneven ground, and unpredictable weather conditions.

The primary objective of our work was to uncover crucial information on ground, groundwater, and geo-environmental conditions to assist SSE Renewables in the design of the proposed development, in an area where limited ground investigation had previously taken place. Anticipated geological challenges included complex metamorphic bedrock, local intrusion by dikes, and faulting along the slopes above Loch Lochy due to the presence of the Great Glen Fault.

Adapting to tough conditions

The execution of the ground investigation involved a flexible approach, adapting to the varied conditions encountered onsite. The extensive ground investigation was conducted from the shores of Loch Lochy to the summit of Sean Mheall, and further into the corrie that contains Loch a’ Choire Ghlais.

To surmount the logistical hurdles presented by the site's remoteness and ruggedness, we utilised specialised all-terrain vehicles and helicopters. These facilitated the transportation of materials for road construction, creating over 10 km of accessible routes to the upper works investigation.

Our site team worked under challenging conditions, particularly at Sean Mheall, where drilling was carried out 24 hours, 7 days a week, with staff living in self-contained accommodation 690 m above Loch Lochy, with the only access being by helicopter. The dedication of our staff to deliver quality results at such a challenging site exemplifies their embodiment of Fugro’s core values and helps us strive towards our mission of creating a safe and liveable world.

Corie Glas project images and videos

Corie Glas project images and videos

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Helicopter utilised for upper site access

Execution of works

The scope of investigation encompassed a variety of methodologies which included rotary cored boreholes (up 650 m deep, some inclined), trial trenches, specialist in situ hydrofracture testing, geophysics surveys (overwater, surface and downhole), detailed soils and rock logging, geotechnical and geo-environmental laboratory testing and groundwater monitoring.

The cumulative drilling meterage covered by Fugro amounted to an expansive 1800 m throughout the duration of the project.

Specialist equipment was installed in the boreholes, allowing longer term remote groundwater monitoring to be made available, without the need to return to site. This was key to our approach as it ensured that disruption to the landscape was onsite and demonstrates our commitment to ensuring the environment can be reinstated in the least possible time following the works. Data delivery was expedited in real time through our advanced web-based platform, VirGeo®, enabling seamless collaboration and access to the data between Fugro, SSE Renewables, COWI, Stantec and the entire team of contractors.

Collaborative approach

Ensuring effective communication of information and good working relationships between all parties involved was key to the success of this ambitious and cutting-edge project. The investigation was tailored to meet the needs of the specific conditions of the expansive site, with collaborative discussions on the most efficient way forward and quick responses to onsite challenges. This approach allowed SSE Renewables to progress through their delivery schedule and incorporate the high quality of data needed to inform the design stage.

Through comprehensive ground investigations, Fugro not only contributes to the advancement of sustainable energy solutions but also fosters positive impacts on the local community through enhanced energy security. This initiative reflects our core values of integrity, innovation, and environmental stewardship, positioning the company as a trusted partner in driving positive change and shaping a more sustainable future.

Key project metrics


km of temporary access roads constructed


metres drilled at deepest borehole location


metres elevation of on-site drilling

Virgeo user_low res


At Corie Glas, we facilitated the delivery of data to SSE by utilising VirGeo®, our cloud-based information delivery, engagement and management platform that provides a single source for accessing and organising various streams of integrated, real-time Geo-data. The platform allowed SSE to easily access and interpret the data through a single sign-on that required no experience with geographic information systems or specialised software.


VirGeo® is our cloud-based information, delivery, engagement and management platform that provides you with a single source for accessing and organising various streams of data and documents throughout the asset life cycle.

Fugro’s work at Coire Glas has enabled the collection of high-quality ground data from a range of challenging locations. Through collaboration with Fugro and our Consultants we were able to adapt to the challenges and optimise data collection.

Jessica T Smith

Senior Engineering Geologist | SSE Renewables

Blyth decommissioning project

Our work in the field of renewable energy

Fugro plays a crucial role in the growth of the renewable energy sector by enabling developers to assess site conditions, mitigate risks, and optimise the design and installation of renewable energy structures.

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