Project Complete: Avoch Burn - Landslip Remediation

7 May 2021

Gabion Basket Retaining Wall | Avoch | The Highland Council | 2020

McGowan Environmental Engineering were appointed as Principal Contractor by The Highland Council with Fairhurst fulfilling the role of project engineer. The focus of the project was to stabilise an existing slope failure to the rear of residential gardens immediately adjacent to the Avoch Burn.

The project was located in a residential area with restricted access. We engaged with surrounding residents from the outset through advance notices and maintained ongoing dialogue throughout, to raise awareness of our scheduled movements and on-site activities.

The slope failure was created by high-flowing groundwater and we incorporated temporary drainage solutions into the permanent design, undertaking excavation works in small stages to ensure continued slope stability. The gabion baskets were completed on-site and constructed in stages to form a pyramid structure, consisting of 9 baskets per linear metre. The structure was hand placed / faced and filled with permeable stone and materials that had been delivered to site.

Drainage was installed along the full length of the works with spurs utilised to connect groundwater flow points. We devised and implemented a soil management plan to resolve further site challenges such as extensive surface water and soft, saturated ground conditions.

The risk of water contamination was high given the proximity of the works to the Avoch Burn and this was mitigated by the installation of silt netting, drainage, culverts and carefully considered access routes. We pride ourselves on being Naturally Different through our environmentally sensitive and sympathetic approach. To further ensure disruption was minimised, all gardens and accesses impacted by the works were reinstated and the surrounding natural habitat was restored.

Ryan Derrick (Senior Engineer) from Fairhurst, commented:

“Working with the McGowan Environmental Engineering team was a pleasure from start to finish. They provided a streamlined, honest approach to the work and were very responsive and proactive to the requirements and challenges faced on site. We found the team to be excellent communicators and they displayed a very thorough engineering knowledge that dramatically helped to simplify the construction process.

McGowan’s showed a keenness to be involved in the project from the very beginning and were appointed due to their experience and enthusiasm towards environmental engineering. We found them to be a contractor that could be relied upon from the very outset and the determination to complete all works on time and on budget was incomparable. We would have no hesitation in recommending McGowan Environmental Engineering as a contractor that can deliver within tight deadlines and add value to any project.”

McGowan Environmental Engineering were delighted to assist The Highland Council on this project and we look forward to working with them again in the future.