Coastal Protection

Geotextiles and coastal protection
Geotextiles can be used in a variety of coastal protection applications, such as beach nourishment, dune stabilisation and seawall construction. For example, in beach nourishment projects, geotextiles are often used to help hold the new sand in place, preventing it from being washed away by waves and currents. In dune stabilisation projects, geotextiles are used to help hold the dune in place, protecting the beach and coastal properties from storm surge and wave damage.

Typical applications

  • Erosion protection
  • Seawall construction
  • Dune stabilisation
  • Beach nourishment
  • Rip-rap structures


  • Geotextiles provide an effective replacement for starter layers, saving in materials, transport, carbon and installation costs
  • The amount of material sinking into the coastal sand is minimised, with the textile preventing drainage stone being lost into the soft subsoils
  • Differential settlement is reduced, helping with long-term alignment of revetments or breakwaters
  • Available in widths up to 6.5m
  • The textile can often replace the need for a granular layer

Erosion Protection
When used in seawall construction, geotextiles are placed between the seawall and the water to help prevent erosion and scouring at the base of the structure. This can help prolong the life of the wall and geotextiles are often used in combination with rip-rap (also known as armour stone) to provide an additional layer of protection to the structure.

One of the main advantages of using geotextiles in combination with rip-rap is that it creates a more stable and durable coastal protection structure. The geotextile provides a layer of protection against erosion by holding the soil in place, whilst the rip-rap provides a layer of protection against wave action and storm surges. Additionally, the combination of the two materials can help to dissipate wave energy, thereby protecting the beach, its sand dunes and nearby properties.

Terrex CG for Coastal and Marine Applications
Terrex CG geotextiles are specially engineered to provide exceptional performance in separation, filtration, and protection – whilst maintaining reduced thickness compared to traditional geotextiles. These geotextiles offer benefits in coastal protection beneath concrete defences, and can also be used for the protection of impermeable membranes.

ABG Terrex CG coastal geotextiles are designed to be used as filtration and separation layers in hydraulic defence structures. Placed onto lower permeability beach materials they prevent the migration of fine particles, while permitting the free passage of water. This creates a stable and consistent bedding layer, often replacing the need for more layers of armour stone and generating significant cost savings.

The advanced Terrex CG geotextile range is often used as a cost-effective alternative to traditional lining layers and provides benefits for toe design applications.
The range has been designed to resist damage during construction loading, with high strength and elongation properties that prevent tearing or puncture.

Filtration & Separation
The inclusion of an appropriately sized and weighted geotextile at the interface with the beach will retain fine particles and preclude them from being washed away, whilst permitting the free movement of water.

In a geotechnical application, a filtration system must function throughout its complete deign life without clogging, and unlike other filter applications the system cannot be easily replaced.

Rather than stopping all particles within the filter, the correct geotextile pore size is selected that allows some smaller particles to pass through. The structure is then stabilised, with larger particles held in place. Once in contact, the larger particles restrict movement of the remaining smaller particles and stabilise the entire soil layer.

Sandex Coastal Protection

Sandex is a geocomposite consisting of a layer of quartz sand between a nonwoven geotextile and a nonwoven composite with scrim component, needle-punched together to provide internal reinforcement.

Sandex 5000 GSL provides a heavy-duty displacement resistant composite mat for protection, filtration and separation.

Designed to provide a displacement-resistant filter, the Sandex composite comprises four-layers with encapsulated quartz sand that allows the sinking / installation of a geotextile filter in even the most challenging conditions.

Additional information

Contact ABG for further information

Fill out our quick contact form with your product, application, technical or sales enquiry and one of our team will be in touch soon.