Salix's Ready-filled Rock Mattresses provided a solution to flood protection works needed on the River Exe. This quick and cheap approach provided a stable, natural embankment on the high energy intertidal river.
Salix was approached to find an ecologically sensitive design approach to replacing tradional gabions and blockstone along a stretch of the River Exe.
Salix’s pre-filled Rock Mattresses fit the bill perfectly.
This approach was found to be cheap and quick to install and resulted in robust slopes and a natural profile. This was required as the tidal nature of the river reduced the working time to one week in every four.
The Rock Mattresses also provide valuable habitat for invertebrates. This encouraged wildlife to thrive without losing the mattresses proven ability to stop erosion in this very dynamic environment. Mullets were found feeding off the banks within a month of installation, a crucial factor as this stretch of river is important for fishing.
The Flood Protection project
As part of the second phase of the Exeter Flood Protection works BAM Nuttall installed a new flood compensation area. The original design was modified, reducing the quantity of block stone along the waterline by installing Salix’s 250mm deep pre-filled Rock Mattress.
There was a site visit by the Environment Agency and the client’s engineer to inspect the work which they found very impressive. They were all full of praise for the fantastic result and the fisheries officer was ecstatic at the sight of the mullet.
BAM Nuttall worked with Salix to achieve savings in time and money to install the system and for the client it also delivered habitat and environmental value. The impressive results have been widely acclaimed. You can read more about the work on the Exeter Flood Defence Works.
Dr Ruth Callaway of Swansea University talks about the wildlife benefits of Rock Mattresses.
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
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
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
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
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
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