River Ebbw Bank Stabilisation - Salix Solutions

Salix worked with consulting geotechnical engineers to provide design and build proposals to stabilise over 800 metres of steep riverbank composed of highly erodible colliery shale.

6 Size Of Blockstone That Was Replaced With Bioengineered Solution On Over 1.5km

River restoration

Part Of The Reach Seven Years Later

Size Of Blockstone That Was Replaced With Bioengineered Solution On Over 1.5km

Part Of The Reach Seven Years Later

Salix worked with consulting geotechnical engineers to provide design and build proposals to stabilise over 800 metres of steep riverbank composed of highly erodible colliery shale. Initial proposals looked at the extensive use of large blockstone to stabilise the bank.

Salix wanted to explore the possibility of using greener and more cost effective bioengineering methods which would provide underlying engineering stability whilst providing an ecological resource and improving the visual landscape.

Bank gradient 1 in 1.5 Slope length 10-15m Water depth (1:100) 4m Velocity (1:100) 4.2m/sec Discharge (1:100) 80 cumecs

The toe of the bank was protected using a combination of Rock Rolls and living willow brushwood faggots. The upper bank was protected using two high performance erosion control mats, VMax³ P550 and VMax³ C350.

Independent research and thousands of applications across the world have shown these products to be able to withstand extremely high flow velocities (7.6m/s – P550 and 6m/s C350) when vegetated.

Even prior to vegetation establishment the “composite” fibre layer provides exceptional erosion control performance (3.8m/s – P550 and 3.2m/s – C350).

Rock Roll & Live Willow Toe Detail With VMax C350 Above

Installing VMax P550 Over Reinforced Soil

Installation Complete

Growth and vegetation one year on — One Year Later

Products Used

VMax³ C350

VmaxC350 is a permanent Turf Reinforcement for reinforcing soils. The VmaxC350 incorporates a coir fibre layer to provide instant erosion protection, whilst the three-dimensional grid provides significant long-term protection.

Rock rolls provide an instant flexible solution to many scour problems

Pre-filled Rock Roll

Rock Rolls are a robust and permanent revetment for use around reservoirs, shorelines, lake edges, streams and river banks. They are cost-effective revetments that are suitable alternatives to rock rip rap and gabions in many scour applications.

VMax P550 On Reinforced River Bank

VMax³ P550

VMax³ P550 is composed of a permanent, ultra-high-strength, three-dimensional matting structure incorporated with a permanent 100% polypropylene fibre matrix.

Details

Client: Merrimans Ltd
Location: Risca, South Wales
High Energy Rivers, Rivers & Water Courses, Urban Rivers

Cross Sections

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We have worked with Salix on a number of projects throughout East Anglia over the last 6 years, and we have always found them to be highly professional and competent. We have used their services as suppliers of quality wetland plants, with a traceable provenance, and as contractors to both supply and plant the wetland plants. In addition we have always relied on the technical advice and knowledge of David Holland, in particular, to help answer queries from our clients regarding wetland planting schemes we have been involved in, this is an added value part of their service, for which we are grateful.

UPM Tilhill

HydraCX gave an immediate impression the embankment was grassed, making it more visually pleasing to our travelling customers. The rapidity of grass growth was exceptional and it added additional strength to the slope surface.

Network Rail

We invited Salix to re-landscape the watercourse through a design and build project. The works to the watercourse were completed within two weeks of starting on site and, despite a number of prolonged heavy rain events both during and after the works, the pre-established coir rolls and pallets all began putting on new growth within a matter of days providing the watercourse with instant channel vegetation and protection to the toe of the banks. The VMax reinforcement used to stabilise the slopes has also prevented any erosion to the sandy soil beneath and has allowed the rapid establishment of grass which wouldn’t have otherwise been possible.

South Ribble Council

Your staff are always friendly, knowledgeable and helpful and we have always been pleased with the service and the quality of the wetland plants and planting services. Technical knowledge on erosion control is also excellent. Keep up the good work!

Living Water Ecosystems Ltd

Atkins has worked with Salix on a number of projects, collaborating on design concept, trialling and implementation. We have found their experience valuable in delivering cost effective and environmentally functional solutions.

Atkins

We used HydraCX for the first time on a Network Rail project in Chipping Campden. We wanted to establish vegetation growth as quickly as possible on a slope with poor ground conditions without the need for importing topsoil due to possession time constraints. HydraCX provided an excellent growing medium for rapid germination.

Carillion Rail

Excellent overall performance – very approachable and offered a good sustainable solutions to rectify a significant erosion scour to the river foreshore without comprising the existing flood defence. Carried out work to agreed timescale and budget. Certainly would value their future input.

Environment Agency, Leeds