Coastal and river erosion protection
An alternative to armour units and tetrapods: TECCO CELL is a cell built on site from marine-grade stainless high-tensile mesh, tensioning hardware, geotextile and local stone fill. It dissipates wave energy in a permeable body and needs no transport of heavy blocks.
The problem
At coasts and river banks, the classic answer for a protection structure is heavy rock armour, concrete armour units or tetrapods. They have three problems: rock of the required size is not available in every region and is hauled from far away, heavy block work carries a safety risk, and concrete blocks and transport mean high carbon emissions. Where a seafront, a coastal road, a port fill or a river slope is losing ground, the first question is: which wave and flow condition, which section, for how long.
TECCO CELL
TECCO CELL, developed by Geobrugg for coasts, is a cell system built on site from marine-grade stainless high-tensile steel mesh (TECCO G65/3 stainless), tensioning and connection hardware, a geotextile layer and locally sourced stone fill. The cells stand by their own weight and integrated structure; as water passes through the cell, wave energy is dissipated and scour in front of and behind the cell is prevented. The open structure allows plant and animal life; from a distance the structure is not visible.
| Topic | TECCO CELL (manufacturer data) |
|---|---|
| First application | Beesands, South Devon, 2016; an adjoining 80 m added in 2021 |
| Durability | According to the manufacturer, no visible corrosion in the mesh after more than 7 years in service |
| Monitoring | University of Plymouth: continuous monitoring programme with topographic survey, laser scanning and drones |
| Fill | Local stone and gravel; no transport of heavy blocks; according to the manufacturer, a carbon footprint more than 50 % lower than rock armour |
| Mobile version | TECCO CELL Mobile: cells are filled and tensioned in advance in a safe area and placed by crane or pontoon in hard-to-reach spots; for emergencies |
The same mesh family is used on slopes as TECCO SYSTEM3. For how the carbon calculation is read and how it enters a specification, see the article carbon footprint in coastal protection (Turkish).
Comparison
| Criterion | Armour units / tetrapods | Rock armour | TECCO CELL |
|---|---|---|---|
| Material | Precast concrete | Large blocks, often from far away | Local stone + stainless mesh |
| Heavy equipment | Needed | Needed | Cells are built on site by hand and with light machinery |
| Coastal profile | Changes | Changes | The existing profile is kept; the cell is flexible and adapts to changes in beach level |
| Appearance | Prominent | Prominent | Not visible from a distance |
The decision is made with the measured wave height and direction, tide and beach geometry; no system is proposed before these numbers are taken during the survey.
What Artusa does
Survey and measurement of the coastal section, design of the cells together with the manufacturer, supply of local fill material, installation and acceptance. For protecting coastal roads and infrastructure it is assessed together with the other systems of the debris flow and landslide family. For a quotation, contact.
Source: Geobrugg AG, "Sustainable protection against coastal erosion" (TECCO CELL) brochure.