Geosynthetics for erosion control on trenches and brooks
Trenches and riverbank erosion control describes the stabilisation of watercourse banks and channel slopes against erosive forces from water flow, wave action and rainfall. Unprotected riverbanks lose material rapidly under hydraulic loading, threatening structures, habitats and flood defences. Secumat® erosion control mats, nets, and rolls provide immediate, long-term protection for streams, ditches, treches and brooks. They are adaptable to soft ground, steep slopes and areas where vegetation establishment is required.
Stabilisation and erosion control of brook/trench beds, banks, and slopes against rainfall and wave-induced erosion forces.
Secumat® erosion control systems (permanent and temporary variants) applicable at and below waterline, on soft cohesive soils, sandy embankments, and steep slopes
Trench and brook erosion: how geosynthetics solve the challenge
Challenges
Bank slumping and toe erosion from concentrated flow
Fine soil particles washed out by subsurface seepage and overtopping
Difficulty establishing vegetation on steep, saturated slopes
Scour at the base of existing structures and embankments
Solution
Secumat® 3D erosion control mat anchored to bank slope surface
Secumat® Green from natural coco or jute fibres (available as nets and rolls)
Secumat® Green bio-based 3D mesh supports seedling root development
Result
Immediate surface protection from first installation day
Structural stability maintained: soil retention function maintained under sustained hydraulic loading
Vegetation establishes within one growing season; natural integration
Typical applications for erosion control on trenches and brooks
Naue erosion control systems are applied wherever watercourse banks, channel slopes and hydraulic structures require durable, vegetation-compatible protection.
Trench banks
Long-term protection against hydraulic erosion and rainfall runoff
Bank restoration
Rehabilitation with natural-fibre mats for vegetation establishment on soft ground
Dyke toes
Stability and vegetation support on flood defence/coastal protection structures
Irrigation canals
Soil retention for brook and reservoir embankments under variable water levels
Robust under hydraulic loading, reliable performance from day one
Bank erosion control systems must perform immediately upon installation, before vegetation establishes and under variable hydraulic conditions. Naue Secumat products are engineered to resist installation damage, anchoring forces and initial hydraulic exposure. The three-dimensional mesh structure interlocks with soil particles from the first backfilling cycle and prevents subgrade washout during backfilling (critical on sandy banks).
Design of erosion control systems: standards and tools
The design of erosion control systems for trenches and riverbanks is based on recognised standards and hydraulic engineering principles. Free software for the design of erosion control systems is available at the Naue Portal. In addition, Naue’s Engineering and Design Department (EDD) supports planners and contractors in selecting the correct product system and dimensioning for project-specific hydraulic loading conditions.
EN ISO 9864: Mass per unit area of geotextiles - product characterisation standard for Secumat® and Secutex®
EN ISO 10319: Tensile strength of geotextiles - performance baseline for erosion control mat selection
EBGEO: Recommendations for design of geosynthetics in geotechnical applications (Germany); reference for riverbank and hydraulic structure design
Fixing of trench and brook beds for protection against sediment displacement and scour
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Practical advantages:
UV-stabilised PP/PE construction withstands prolonged exposure before vegetation cover
Low self-weight enables manual installation on inaccessible steep banks and confined channel sections
Anchoring system resists shear and uplift forces
Geogrid-reinforced variants provide additional tensile strength on steep slopes
Soil retention - when do I need what?
In hydraulic applications, the long-term function of an erosion control system depends equally on surface protection and sub-surface soil retention. When fine particles migrate from the bank into the overlying revetment, voids form and the bank loses mass. This process (known as suffusion) can undermine revetments silently over years.
Erosion control solutions:
Secumat® mats/nets for surface erosion control on banks and slopes
Biodegradable variants available for temporary erosion control on the water-land transition zone in trenches and brooks
Secumat® Green georolls acts as a low bed sill: it reduces flow velocity and acts as a sediment trap immediately upon installation
Decision guide: Secumat® standard or Green variant?
The correct product selection depends on subgrade type, hydraulic loading, the need for underwater installation, and whether vegetation establishment is required. The decision table below as well as the Naue SolutionFinder provide project-specific guidance.
Criterion
Secumat® 601 201
Secumat® Green
Application zone
Above waterline; channel slopes and embankments
Above waterline; slopes requiring vegetation
Subgrade type
Sandy to cohesive banks; separated from fine subgrade by Secutex® nonwoven
Cohesive to mixed soils; well-graded seed bed
Hydraulic load
Moderate to high flow velocity; rainfall and runoff
Low to moderate flow; primary function is vegetation support
Filter function
Via separate Secutex® nonwoven layer (GRK 3-5C) or combined article
Minimal filtration, good vegetational growth
Vegetation target
Long-term PP/PE mat; vegetation grows through open mesh
Temporary bio-based matrix that breaks down over time as the vegetation root system takes over
Benefits from the client perspective
For planners and hydraulic engineers
Norm-compliant design using DWA and BAW guidelines and EN ISO 10319. Secumat® erosion control solutions are tested and documented per applicable standards. Naue´s engineering team provides project-specific design support.
For site managers
Secumat® erosion control mats are lightweight and can be cut on site and installed by hand. Installation on steep or inaccessible slopes is possible with a long-reach excavator for backfilling. No specialist plant or complex formwork required.
Proven worldwide performance
Secumat® products have been deployed in numerous projects worldwide: from drainage channel rehabilitation in Hamburg to riverbank protection in Malaysia. The systems combine ecological compatibility with proven hydraulic performance.
Bed and bank erosion control: frequently asked questions
Bank erosion control describes the use of geosynthetic systems to stabilise watercourse banks, channel slopes and dyke faces against erosive forces including flow velocity, wave action, rainfall and seepage. It is required wherever unprotected soils are exposed to hydraulic loading that exceeds the natural erosion resistance of the bank material, typically in channels with elevated flow velocities, in flood-prone areas or during bank rehabilitation works.
Secumat® products are tested in accordance with EN ISO 9864 (mass per unit area), EN ISO 10319 (tensile strength) and EN ISO 12958 (water flow rate). System design follows EBGEO guidance (Germany) and BAW technical circulars for hydraulic structures. Project-specific design by Naue’s Engineering and Design Department (EDD) ensures compliance with national regulations. Free software for the design of erosion control systems is available at the Naue Portal.
Secumat® mats are cut to the required slope length on site and installed by hand due to their low self-weight. The material is unrolled parallel to the slope, overlapped at joints per installation design, and secured using hardwood pegs (Secumat® Green PinW 30) or anchor trenches at the top and toe of slope. Backfilling is performed using a long-reach excavator where bank access is restricted. A Secutex® filter nonwoven is installed on the subgrade in advance to prevent sandy soils washing through the coarse backfill during high-water events.
Yes. Secumat® Green 60G5 is made from a bio-based polymer. It provides temporary erosion control during the vegetation establishment phase and then breaks down in the soil: in the presence of moisture the polymer hydrolyses and is subsequently broken down by microorganisms. The time to full degradation* in the open environment depends on temperature and moisture and can range from months to considerably longer. Secumat® Green Coco M 450 uses untreated coconut fibre filling with a jute carrier fabric and has a functional duration of up to 36 months. Both products are designed to reduce persistent material residue in sensitive aquatic environments.
Naue Secumat® products are manufactured and tested to ISO standards. Project-specific designs by the Naue EDD are prepared in accordance with national regulatory requirements for hydraulic structures. For German projects this includes BAW technical guidance documents. For projects in other jurisdictions, Naue’s technical team can advise on local compliance requirements and provide the necessary product documentation.
When using Secumat® Green products for riverbank restoration, seeding is typically applied either hydroseeding directly onto the installed mat or by broadcasting native riparian grass and wildflower mixes into the 3D matrix before or after mat installation. The open structure retains moisture and seeds in contact with the soil surface. Local riparian seed mixes that include deep-rooted species (e.g. herbs, grasses) improve long-term bank stability as the temporary mat breaks down. Naue recommends consulting a qualified ecologist for species selection in sensitive watercourse environments.