Case Studies

AquaRockBags for scour problems

The objective of the project was to fill the scour hole & to provide an extension to the existing spillway that prevents scouring downstream

AquaRock Bags used in Erosion Protection

As a result of substantial rain fall in the Sacramento area , severe flooding ensued, leading to significant erosion challenges along Auburn Ravine.

AquaRock Bags used as a Working Platform

A working platform was needed along the banks of the Saluda River in Columbia, SC to allow heavy equipment to be placed on it. This was needed for construction, but it had to be easily removed upon completion. This was the perfect opportunity to use AquaRock Bag.

Habitat Creation at Padnall Lake, a SuDS Solution

SuDS project creates new habitat for wildlife

Erosion Protection on the River Leith, Thrimby, Network Rail

Network Rail had identified an erosion and scour risk at the toe and embankment of one of their assets on the River Leith, near Thrimby, Cumbria.

Restoring Saltmarsh Habitats to Prevent Erosion

Salix’s natural bioengineering solutions, native plants & brushwood fascines, are used to prevent further erosion at West Thurrock

Improving Wetland Habitat at Goodwick Moor, Fishguard

Increasing wetland habitat on a Wildlife Trust nature reserve in Pembrokeshire, opening up a pond and creating an island with soil from the pond

AquaRockBags for Emergency and Temporary Work

Following a storm event in February 2022, a 20-metre section of flood wall in the Derbyshire town of Matlock collapsed.

Jackson Civil Engineering,

Using Carbon Neutral Wetland Habitat to Prevent Erosion in Iport Doncaster

Wetlands were excavated as part of a large, new retail development near Doncaster. Once excavated, the embankments suffered from significant erosion due to sandy soils and wave action. The structural integrity of the embankment was at risk, which would lead to failure of a bund and continued erosion.

Low Carbon Solution to Waste Water Management

Salix grew tens of thousands of native wetland plants for a Integrated Constructed Wetland (ICW) to treat wastewater as part of a Yorkshire Water Wastewater Treatment Works (WwTW).

River Stour Embankment Restoration

Soft engineering solutions presented by Salix, such as Coir Rolls, Rock Rolls and shear stress turf, represent a major cost saving over traditional hard revetments

River Towy, Bank Erosion, Carmarthen

Aqua Rock Bags were installed at the eroded toe of the failing riverbank after it had eroded the bank and caused the footpath to collapse into the River Towy in the centre of Carmarthen.

River Elwy, Pipeline Protection, North Wales

A live crib wall of willow were used to protect a high pressure gas pipe that had become exposed due to significant river bed scour and bank erosion on a section of the Afon Elwy near St Asaph.

Re-naturalisation of the Broadwater Brook

Salix worked with the Sompting Estate, and the Ouse and Adur River Trust to re-naturalise a watercourse, constructing a kilometre of new channel for the Broadwater Brook.

Erosion protection on the River Gripping

Salix supplied AquaRock Bags to provide an environmentally sensitive solution yet robust solution to protect the toe of the embankment from further slips and limit the potential for further erosion.

Restoring the River Beane, a Chalk Stream

Salix enabled the restoration of wetlands and chalk stream habitat whilst bypassing a weir which was a listed heritage feature

Restoring the River Mimram, Tewin

Salix were commissioned to restore part of the river Mimram whilst protecting the local population of water voles and increasing the biodiversity

Re-naturalising River Nairn

Salix worked on the River Nairn in an award winning project to renaturalise the river, allowing it to meander again and restoring river processes.

River Quaggy: Lewisham

Salix provided Coir Rolls and Coir Pallets to provide instant vegetation and habitat on the deculverted River Quaggy.

Hoveton Broad, Wetlands Restoration

The Hoveton Wetlands Restoration project aims to deliver the restoration of Hoveton Great Broad (HGB) and Hudson’s Bay. Salix were appointed by Natural England to complete a major desilting and dredging project

Coastal Road Protection

2T AquaRockBag® are used as a temporary measure to support the road and prevent scour during winter

Scour Prevented by AquaRockBags

AquaRockBags® were installed by the local council highways team to prevent a road subsiding due to scour and erosion caused by the adjacent watercourse.​

Yearl Weir

As an ecologically sensitive site the use of traditional hard engineered bank protection was not an option and Salix’s bioengineered designs were favoured.

High Energy Inter Tidal Solution on the River Exe

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.

Reservoir Dogs – Shoreline protection

Salix were brought in to help with a sensitive erosion problem on a reservoir shoreline in North London. Ecologically sensitive solutions were used which will create habitats and improve amenity value.

Our Rock Products are the (Jack’s) Key to Preventing Erosion

Jack’s Keys needed a rapid response to scour and erosion problems.
Our pre-filled Rock Mattresses and Rock Rolls were the answer, our Menzi Muck Spider machine was able to climb in and place them in the river bed.

Intertidal Planting Solution on River Thames

Creating a reed bed on an intertidal part of the Thames river is challenging – but Salix achieved a fantastic result as a consequence of their unique design approach.

Flooding and erosion prevention in Sheffield

When a flashy stream was unearthed in Sheffield Salix were brought in as specialist experts in erosion management by the Wild Trout Trust. The Porter Brook was subject to regular flooding, if it rained on the Peaks then the city centre would flood.

Erosion Management on Railway Embankment

Salix were brought in as specialist experts in erosion management at an embankment in Rodbourne.

Protecting a Pipeline in Carmarthen

We installed erosion protection products like our Coir Rolls and Rock Rolls at this site where a pipeline was exposed in the river bed

Erosion Control at Laurel Farm, a Network Rail Site

Scour protection provided by Rock Mattresses at a Network Rail site where the river had undercut the river bank, endangering the embankment above.

Salix Erosion Products Used in Flood Protection Repair Works

Salix’s erosion management products used in works to repair flood defences. Rock Rolls, Coir Rolls, native wetland plants and VMax C350 were all essential ingredients.

River Bank Erosion Management at Wisley Golf Course

Extreme river bank erosion rectified by regrading the river bank and using Coir Rolls and Coir Pallets, preventing erosion naturally

Erosion Control at SuDS project

Rock Rolls and Rock Mattresses are both easy to put into place, prevent erosion and can withstand high flows whilst allowing for the natural establishment of plants.

Naturalising a Stream at Bedlinog

Constant flooding and erosion had been causing some serious problems for Merthyr Tydfil Council who manage an old reclaimed tip site, close to the village of Bedlinog in the Taff Bargoed Valley.

Flood Alleviation at Tregaron

The aim of the project was to protect around 100 houses and businesses that had been subjected to increased flood threats. Constant flooding was a problem with this very flashy river where it passes through the town.

River Washford Roadwater Erosion Protection

The increasing frequency of flood events on the River Washford required the existing system to be replaced and improved.

River Washburn Restoration

Salix were approached as river restoration experts and because of the innovative Menzi Muck Spider machine which is capable of climbing in and out of a river causing little disturbance.

Silent Valley Erosion Control

HydraCX™ was applied to 125,000m2 of poor, erosion prone soil at a large landfill site in Ebbw Vale, South Wales. HydraCX is a hydraulically applied erosion control product that protects slopes against soil and seed loss from heavy rain and wind from day one of application.

Cwmparc River Restoration

Salix worked with Natural Resources Wales at Cwmparc in the Rhondda Valley to renaturalise the water courses in order to reduce flood risk and increase biodiversity.

River Dulais, Rhosmaen Llandeilo

Salix’s River Dulais project demonstrating the use of large woody debris (LWD) is now ten years old and has been is included in the manual of River Restoration Techniques.

Green Swales on Roadside

Soft engineered ‘Green Swale Grass Channel’ attenuates road run-off water, filters suspended solids, and traps hydro carbons and heavy metals, significantly improving water quality.

Woodberry Wetlands

Desilting a large reservoir in the heart of London and creating a new wetland habitat. Dredging silts enabled us to create 13,000 square metres of new reed bed

Erosion Control on Loch Garry Spillway

Erosion control using Tensar VMax P550 on Loch Garry spillway and embankments

Restoring East Tullos Burn

East Tullos Burn project transformed a waterway from a straight, hard-engineered channel, into a natural stream, functional floodplain and wetland habitat.

Naturalising Norfolk’s Chalk Rivers

Salix has helped the Norfolk Rivers Trust to improve wildlife habitats on the chalk River Babingley, Hillington Estate near Flitcham, and River Nar at Pentney, near Kings Lynn.

Sandwich Flood Alleviation and Spillway Scheme

The £21.7 million flood defence scheme involved works on 16 individual reaches of the river and it reduced the risk of tidal flooding to 488 homes and 94 commercial properties in Sandwich. Client – Jackson Civil Engineering working on behalf of the Environment Agency.

Scour Protection at Lhanbryde Spillway

Following the 2005 £2million Lhanbryde Flood Alleviation Scheme, near Elgin in Moray, in Summer 2014, Salix worked with Royal HaskoningDHV engineers to improve erosion control on the dam’s spillway.

Darwen Bank Stabilisation

A 120 metre reach of river had been subject to ongoing bank instability issues. A gas pipeline set in the bank was dangerously close to being exposed and bank revetment options were considered.

River Rhiw Bank Protection

Salix were awarded the contract and began works to carry out 300 metres of riverbank protection to protect this existing exposed high pressure gas pipe in March 2013.

Olympic Park Wetlands

Salix were involved in making the Olympic Park a reality, when we were awarded the prestigious Tier 2 Contract in 2009 to grow all the wetland and wet wildflower plants…

M25 Road Widening

Salix were tasked with greening up a 45 degree slope consisting of 6F2 fill. The initial design was a covering of 150mm of topsoil over an area of about 8,000m2 using a geocell product attached to the surface of the slope to contain the soil and prevent it from slipping.

Kingsbury Tamworth Rail Line

Salix applied HydraCX in September 2009 to slopes consisting of 6I/J fill material with no imported topsoil covering the surface. The project was monitored each year to see how the vegetation established.

Wilderness Lake

The Wilderness Lake is an important coarse fishery and recreational resource on the edge of Porthcawl in South Wales. It also functions as a flood storage area for the surrounding urban areas.

Gloucester Business Park

A new warehouse complex required a large balancing pond to take surface runoff water. The pond had steep sides which required some form of ground stabilisation.

Cwmbran Boating Lake

The boating lake was a popular local attraction and fishing lake. The lake edges were in bad repair with little or no marginal vegetation. Floating islands were also required to add further habitat for fish and wildfowl.

Longham Lakes

Working for Bournemouth & West Hants Water, Salix were appointed as Main Contractor to undertake 2km of bioengineering works to stabilise the shoreline of a new reservoir.

Ramsden Bellhouse

A series of potentially dangerous deep seated failures on a railway embankment required treatment to prevent further slips. The geotechnical issues of ground stability were resolved using soil nailing.

Chipping Campden Rail

HydraCX was sprayed onto 5,500m2 of re graded rail embankments to prevent erosion and establish vegetation rapidly without importing expensive topsoil. HydraCX also replaces erosion control geotextiles.

Foss Dyke Bank Stabilisation

A rise in pleasure boating on the Foss resulted in severe boat wash. Monitoring revealed that the rate of bank erosion was up to 2.5 metres in a year over a 2km stretch.

Pewsey Rail Embankment

A rail embankment had slipped and was reinstated with soil nails providing geotechnical stability. Birse created working platforms with imported stone and then used a soil cell system to retain about 150mm depth of soil on slopes up to 43 degrees.

Afon Gwydol Embankment

Works were required to repair an eroding railway embankment adjacent to the river. This resulted in the embankment encroaching into the river, causing erosion problems on the opposite bank belonging to a local farmer.

Papworth Reedbeds

After a competitive bid process, Salix designed and built a tertiary treatment reedbed for Anglian Water at their Papworth STW. Salix partnered with Pete Worrall of Penny Anderson Associates and a unique design approach was developed.

Salwarpe Reedbed

As part of a new large reedbed creation project Salix contract grew and planted out 125,000 reed plants grown from local provenance seed stock. Seed was hand collected and processed by Salix specialists from an adjacent existing reedbed.

Twycross Zoo Wetlands

As Principle contractor, Salix constructed a 3 hectare wetland system to provide waste water treatment and habitat creation. 18 integrated ponds, wet grassland, reedbeds and ditches were constructed for Twycross Zoo.

Pembroke Commons

1 km of new and existing channel was enhanced using bioengineering techniques as part of a flood protection project in the centre of historic Pembroke in West Wales.

River Pinn Enhancement

Salix designed and constructed a stream enhancement project at a gas pipeline river crossing as ecological mitigation to a degraded reach of stream as part of a major pipeline project.

River Thaw Enhancement

Salix were asked by Environment Agency Wales to advise on methods to restore a 100 metre reach of the River Thaw which had been subject to physical degradation by overgrazing and cattle poaching.

Conwy Flood Alleviation and Spillway Scheme

Salix supplied 9000m2 of VMax3 Shear stress turf in September 2009. Just 2 months later the area experienced the worst flooding in 25 years of recording with floods exceeding the 1:30 year events of 2004/2005.

River Ebbw Bank Stabilisation

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.

River Gwenfro

A private developer had back gardens adjacent to a river that when in flood created severe scour issues. Initial river modelling indicated flow velocities in excess of 3.5m/sec.

River Pipeline Crossing

Salix were invited to submit a bioengineering solution to solve an erosion issue at a pipeline crossing in West Wales. The solution used a combination of locally harvested willow and Rock Rolls to provide a stable revetment in this cobble bed river.

River Roding Bank Protection

Salix advised engineers Halcrow on bioengineering methods to stabilise a regraded slope as part of an inter-tidal river enhancement project. The existing vertical retaining wall provided no habitat value.

River Roding Enhancement

The River Roding is an inter-tidal river and these works were undertaken 100m upstream of the Barking Barrier, Greater London. The works were part of an Environment Agency environmental enhancement project with both flood defence and nature conservation in mind.

Dan Y Lan Landfill Slip

The finished slope was 36 degrees, 40 metres in height and 60m wide. 250mm depth of topsoil was required, rather than the nominal 50-75mm, as cover for marginally contaminated on site fill material.

Calverton Tip Drainage

Colliery shale and sandy soils have one thing in common; both are highly susceptible to erosion by flowing water. Both soil types were present on site.

Waverley Colliery Reclamation

A large drainage channel designed to take flows of up to 3m/sec was created to take runoff water from a 741 acre site at Waverley, one of Europe’s biggest collieries.

Locke Park Lake

Locke Park Lake had become silted to the point that it could no longer be safely used for boating. Salix were employed as main contractor to de-silt the lake…

Beacon Park

Salix were employed by main contractor Casey to undertake the restoration work to Beacon Pool for Lichfield Council on this Heritage lottery funded project.

Kelham Island Goit

Salix were contracted by Mansell construction to dredge the contaminated Goit forming Kelham Island and working closely with ecologists ECUS to create marginal habitat.

Water Vole Habitat Works

Salix successfully tendered for a pilot project to improve marginal vegetation along the River Wandle. The project formed part of a wider scheme to reintroduce water vole to the river.

Upper Lake, Perton

A two hectare area of open water had extensive embankment erosion due to massive populations of Canada Geese which created public health & safety issues.

Grand Union Canal

The project aim was to restore a wetland area on the banks of the Grand Union Canal for the benefit of wildlife and the fishery. The scheme design ensured that no material was taken off site and that particular focus was on creating suitable habitat for Water Voles and amphibian species such as Newts.

Treboeth Cobble Channel

A new development had slope stability issues due to an adjacent cobble bed watercourse badly eroding the soils and downcutting the bed within the channel.

Soham Lode Re-visited

An important water vole site at Soham Lode required emergency re-lining of the perched section of the reach (approximately 600m) Following the emergency works, Salix were awarded a Design & Build contract on a competitive bid process…

Water Vole Habitat Mitigation

Medmerry is one of the stretches of coastline most at risk of flooding in southern England. The overall scheme involves building major new sea defences inland and allowing a new intertidal area to form…

River Tywi

Salix were awarded a design and build contract to prevent further erosion of a section of the riverbank and reinstate a scour hole threatening a high pressure gas pipeline on the River Tywi.

Worden Park Leyland

Following works within Worden Park to remove a culverted section of Cricket Field Brook that was the cause of flooding to neighbouring residential properties, a long term solution was required…

Railway Lane, Lewes

The integrity of the existing blockwork facing was deteriorating as a result of the tidal inundation and draw-down cycles together with areas of groundwater seepages emanating from the slope profile.

River Teme Restoration

The River Teme is a sensitive SSSI and SAC river and over 150 metres of severe bank erosion was threatening a National Grid pipeline.