The A.G.A Group undertake a variety of river management and restoration projects and is a major player equipped and experienced to employ a wide range of recognised techniques.
We provide an extensive range of materials and systems for Erosion Protection on
- River banks and wetlands
- Lake/reservoir banks and shores
- Dams, revetments and balancing ponds
- Unstable and over-steep slopes
- Spillways and irrigation channels
We make use of the most appropriate materials be they natural or man-made, more often a combination of both. In this way we can provide immediate short or long term surface protection that can mean a rapid return to the location's natural state.
Bioengineering and soft engineering erosion control measures
Pre-planted coir rolls provide an excellent alternative to hard revetment to establish a ‘soft’ and effective long life method of erosion control or to establish immediate habitat. They also provide improvements in site biodiversity and encourage flora and fauna into the area. A.G.A. coir rolls are mature, pre-vegetated with strong root systems so establish rapidly in the growing season.
Vegetated coir pallets offer an excellent natural solution to establish marginal aquatic vegetation in lakes, ponds, rivers and stream banks. The success of the coir pallets lies in their diversity, they are so versatile and can be used to protect against erosion or provide habitat. Where water bodies have been created by using synthetic membranes and liners, A.G.A. coir pallets will often be the most suitable way to establish aquatic vegetation into the water body thus help to establish aquatic flora and increase biodiversity for key species.
Erosion control blankets are usually woven from a chosen material and will slow down the speed at which water moves across the surface. There are different types of erosion control blankets, some that are synthetic some that are natural and others that are both synthetic and natural.
Faggots are widely used in conjunction with many other materials to facilitate our bioengineered solutions for environmentally sensitive projects. Faggots can provide support for coir rolls and pallets to ensure that they sit at the correct water level, they will also offer additional erosion protection to the bank, particularly to the often vulnerable ‘toe’. Faggots provide a very important erosion control technique to manage scour below the water level where coir alone would not address the problem, once installed they have a very long life and become an integral part of the project.
Live faggots made from willow are used to provide a living and very sustainable option, as well as providing long-term erosion control they also improve biodiversity by increasing habitat.
A.G.A only use FSC certified suppliers to support best management practices of the worlds forests.
A.G.A rock rolls can be an excellent option alone or as a component of bank revetments. Originally developed by A.G.A primarily to be used alongside coir rolls as a flexible sub-surface but permanent support gabion, they also provide excellent erosion control.
In turbulent and fast flows, rock rolls solid foundation onto which vegetated coir rolls can be installed, provide roots with the medium into which they grow and establish into the voids giving long term erosion control, bank support and habitat enhancement.
Geotextile fabrics & composites.
Geosynthetics offer many benefits over traditional construction techniques, by reducing project costs, construction times and reducing the volume of natural materials that are used and therefore reducing the environmental impact of transportation
Bank-side erosion is a common riverine problem, particularly in fast flowing (artificially straightened) channels and there are a number of revetment techniques which can be employed, the choice of erosion prevention measure employed is heavily dependent on site conditions and as such there is no one cure all.
A.G.A GeoCell is a soil confinement and reinforcement web designed to retain the soil on banks where the slope angle is greater than the friction angle of the soil. The inter-geo cellular drainage holes prevent saturation of the fill material to both protect slopes and also control surface erosion.
AGA GeoCell can also form flexible revetment structures for lining ditches and water channels and may be filled with concrete or crushed stone. The holes within the web can be used to attach securing ropes on steep slopes.
A.G.A. GeoGrids provide soil reinforcement for steep earth slopes, retaining walls and the stabilisation of weak ground. They create a reinforcing function by supporting the penetration of soil/rock particles or other geotechnical materials through the grids apertures by interlocking the particles.
Geo-Grid reinforced steep slopes and embankments help to control erosion and the stabilisation of river and reservoir banks, Geo-Grid can be easily vegetated and cost significantly less than conventional concrete or gabion retaining structures.
A.G.A Span. Vertical bank protection
A.G.A Span is a specialised product for vertical bank protection. It provides a high-quality and very economical form of erosion control. A.G.A Span is a prefabricated, pocket revetment fabric, which is UV stabilised, relatively easy to install and will last for a very long time.
After installation, and with time, the face of the A.G.A Span will start to green up as it becomes colonised by natural algae and lichens, providing a more sympathetic aesthetic appearance
The technique can be further softened by using pre-established coir rolls to provide a vegetated element to the face.
This form of bank erosion technique is used in fisheries and along the side of canals as it provides excellent vertical protection against bank erosion.
A.G.A. Advance is a woven geotextile suitable for separating, filtration and reinforcement. It is used in A.G.A coir fibre systems as a sediment retention membrane to prevent the wash out of soil fines from backfill. In high flow situations we recommend using the High Flow material grade to allow this water movement through the geotextile, this is especially important adjacent to a watercourse.
Advance HF woven geotextiles provide outstanding water flow and pore size characteristics that will satisfy even the most demanding hydraulic applications. The uniform apertures across the roll ensure fine particle retention and even filtration characteristics that maximize long term performance by reducing the likelihood of the fabric blocking and clogging.
A.G.A NP300 is a strong and flexible needle punch geotextile that provides protection to prevent soil erosion from beneath a wide range of adjacent AGA, geosynthetics, rock armour and other revetments.
A.G.A NP300 as a separator reinforces poor existing sub-soil by preventing it from mixing with costly imported material that is laid above.
A.G.A. NP300 drainage and filtration geotextile retains particles whilst allowing the free movement of water, thereby keeping separate two opposing layers during severe hydraulic activity. The installation of our NP300 avoids the migration of material between layers vastly improving the surface load bearing capacity. It sustains the free passage of water preserving the sub-soil stability preventing erosion.
A.G.A. ArmorMat is a steel reinforced geomat of polymer that has been extruded onto a double twisted hexagonal steel wire woven mesh. The thick polyamide filaments are designed to be secured to the exposed slope face to prevent surface run-off from causing erosion.
ArmorMat is intended for long-term erosion protection applications, it immediately increases the soil’s resistance to erosion by providing an environment that enhances the growth of vegetation through the mat. Reinforced geomat mitigates climatic erosion forces and loss of vegetation, habitat and land.
Hard engineering methodology for erosion control
Gabions and mattress gabions are a well-established product for use in high velocity and turbulent rivers, revetments, drainage channels and tidal waters. They come in sizes and finish to suite any application making them suitable for most configurations.
They can be stacked, bonded or installed individually, once filled with selected material they form a monolithic retaining wall to control erosion and stabilise earth.
The use of natural stone and other materials on the face of gabions can result in an attractive appearance, moreover they can support vegetation while above or below the water line they provide excellent habitat for a host of different species.
Controlling erosion can call for heavy duty measures. We supply and install piles and other supporting structures in aquatic environs for uses in both temporary and permanent applications. The type and material available ensures we can offer the correct solution for most applications. Our basic materials range ensures maximum strength and durability specific to the project at the minimum weight that is consistent with optimum engineering practices.
Steel Sheet Piles
Precast Concrete Piles
Pressure Treated Timber