When you visit a coastal town or city, you are almost guaranteed to find some form of concrete structure on the beach. Whether they are seawalls or rock armour, these hard (or grey) engineering structures have become common in the coastal landscape. These defences provide much needed protection from coastal erosion, flooding and storm surge events which in turn protect important infrastructure and people living by the sea.

However, the negative impacts of these hard engineering strategies have now been widely documented, and their use called into question. For instance, an area taken up to build a seawall will reclaim crucial coastal habitats such as sand dunes and saltmarshes, which will impact the species reliant on these areas.

It is also widely known that the surface of rock armour or concrete structures support a less ecologically diverse range of organisms and even allow invasive species to outcompete native ones. A less ecologically diverse ecosystem could potentially undermine the ecosystem services (such as water purification or the provision of food) that we use, which will then impact our quality of life as well as the quality of marine life.

How can we improve this?

We need to do more to safeguard the marine environment and protect these ecosystems, not just for the benefit of marine species, but also for our own. Under the SARCC project, we are employing the use of surface textures, which are manipulations to the surface of concrete or any other hard surface in order to create more surface area. As rocky habitat is naturally rough through centuries of physical action from waves and sediment, they contain small (mm), medium (cm) or even large scale (m) changes to the surface including cracks, crevices and rockpools. With the aid of scientifically informed literature, we have created multiple surface texture designs which we have successfully imprinted onto our GeoBlock^TM units.

The potential use of these surface textures is ideal for locations where the creation of natural coastal habitats is not feasible for economic or technical reasons, such as large coastal cities with a high energy marine environment. Our surface textures can be designed to be retrofitted to the surface of existing seawalls which will provide more heterogenous habitat for marine flora and fauna to settle and colonise while also providing much needed protection from ocean forces.

While surface textures within scientific literature are largely limited to tiles that have been retrofitted to existing walls, we are looking into how else our surface textures can be employed, including using our textured GeoBlocks as the foundation for Eco-Reefs in order to support even larger ecosystems in multiple settings.

If you wish to learn more about surface textures, look at our GeoBlock^TM concept or for more information regarding our work into coastal defences, follow the link to the SARCC website.