2023
Exeter, Devon
Deven County Council
John Graham Construction
Pell Frischmann
Marsh Barton Railway Station Vegetated Slope Stabilisation Solution
Challenge
Devon County Council required the construction of stable, reinforced vegetated slopes as part of the Marsh Barton Railway Station development. These slopes were essential to support the station platforms and provide safe, accessible pathways, while also integrating naturally with the surrounding environment.
The project posed several engineering and logistical challenges. A key requirement was to deliver a slope stabilisation solution that combined long-term structural performance with environmental sustainability. The design needed to accommodate approximately 500m² of steep slopes within the station footprint, with inclinations reaching up to 70 degrees. This required a robust reinforced soil system capable of maintaining stability under load while enabling vegetation growth.
In addition to the technical demands, the project involved complex site coordination. Multiple stakeholders, including main contractor John Graham Construction, earthworks teams, and installation specialists, needed to work collaboratively within a constrained construction environment. Careful planning was required to ensure correct installation, appropriate material selection, and adherence to design specifications, particularly regarding reinforcement and backfill performance.
Solution
A comprehensive engineered slope stabilisation solution was developed to meet the project requirements. Pell Frischmann, acting as lead consultant, designed a reinforced basal layer to provide a strong and reliable foundation tailored to the site’s ground conditions.
Devon County Council selected the Green Terramesh system as the preferred retaining solution due to its ability to combine structural integrity with a natural vegetated finish. This modular system enabled the construction of steep, 70-degree reinforced soil slopes while supporting sustainable landscaping objectives.
The installation included one Green Terramesh wall to the northeast of the station supporting Platform 1, and three additional walls to the southeast supporting Platform 2. Together, these structures covered approximately 500m² of reinforced vegetated slope.
To ensure long-term slope stability, Paragrid 50/05 geogrid was used as reinforcement within the soil structure, providing high tensile strength and load distribution. Selected 6I/6J backfill material was placed and compacted to deliver optimal performance and durability of the reinforced soil system.
Ongoing technical support and site supervision played a critical role in the successful delivery. Multiple site visits throughout 2022 ensured correct installation practices, quality control, and alignment with design intent across all project phases.
The completed solution delivered durable, stable, and environmentally integrated slopes that effectively support the railway platforms and pedestrian pathways. The use of Green Terramesh provided a cost-effective, sustainable slope stabilisation system that met both engineering and aesthetic requirements for the Marsh Barton Railway Station project.
Used Products
