Regenerating Gledhow Valley Beck using Nature-based Solutions (NbS)
I’m Karen Dunton, and I work as a Senior Hydrology Consultant in Sweco’s Water Environment team. Recently, my colleagues and I had the opportunity to work on a community project for Gledhow Valley Woods in Leeds. In this blog post, I’ll be discussing our involvement in the project and how we helped to reduce sediment transportation in and around the watercourse using NbS.
Gledhow beck, situated a 10-minute walk from Sweco’s Leeds office, has been the subject of a regeneration project providing nature-based solutions to modern day environmental issues.
The beck is located in a valley which is partially confined by the topographically higher valley slope and Gledhow Valley Road. Gledhow Beck flows downstream into a lake which creates sediment deposition and water quality challenges. These challenges are sourced to sediment transportation from the valley sides, combined sewer overflows, misconnections and outfalls from the road network discharging directly into the beck.
This is where the Friends of Gledhow Valley Woods (FGVW) come into play. A registered environmental charity run by a team of volunteers with the aim of fighting the environmental challenges faced in this area by utilising innovative Nature-based Solutions (NbS).
In 2019 the lake was dredged, the sediment was relocated behind a bunded section to improve the lake as a wildlife habitat and to retain its purpose as a water balancing lake. Having delivered the lake regeneration project in 2019, FGVW aim to manage the influx of sediment into the lake via the beck and lake sides, to preserve the value added to the lake by the regeneration project, while also improving the lake and surrounding woodland for wildlife by creating better habitats.
Sweco have been so easy to work with, providing us with great advice and practical support which would not otherwise be available to our small local charity. The project has significantly improved the woods for wildlife and we have received really positive feedback from the local community. We are really looking forward to working with Sweco on the next stage of the project.
David Miles Community engagement lead, Friends of Gledhow Valley Woods
Sweco’s Role
To help achieve the goals set out by the FGVW, a team of Sweco employees approached the volunteers to provide consultancy advice. While supporting Sweco’s COP26 goals to undertake voluntary environmental activities, the consultants involved were keen to provide support to the local community. After liaising with the FGVW, Sweco identified six potential options to mitigate sediment transportation to or within the watercourse. These options include:
- Bunding of the southern side of the lake to capture and retain sediment transported into the lake
- Dead hedges which would capture sediment entering the lake
- Erosion protection to stabilise banks, reduce erosion rates and capture sediment
- Leaky dams to attenuate small volumes of water and reduce sediment movement within the watercourse
- Flow detectors on the steep valley slope to help slow and disconnect the overland flow network whilst retaining sediment
- Buffer zones in the form of bank top planting
In addition, reed beds were also proposed to provide an effective natural filter, improving the other water quality issues identified. Following the advice from Sweco, FGVW have started constructing some of the innovative nature-based solutions proposed. Photos below show the nature-based solutions in place in Gledhow valley woods, which include dead hedges, surface flow defectors and leaky dams.
Sweco is currently in discussion with FGVW regarding how they can help the next stage of the regeneration project.
Further Information on Friends of Gledhow Valley
FGVW is a community group that was established in 1996 to address environmental concerns in the Gledhow Valley. Their primary goal is to conserve and enhance and protect the natural beauty of the woods and increase public awareness about the area. Read more: FGVW – All About Us – Introduction to the Friends of Gledhow Valley Woods