Mumbles Coastal Protection Project - Part 2, Swansea, Wales

In Mumbles, a coastal community on Wales' Swansea Bay, the sea wall was renewed along a stretch of around 1.2 kilometres. It is designed to protect the promenade, buildings and people from storm surges, erosion and rising sea levels.

The starting point was a research question from Swansea University: which surface texture provides the best conditions for marine life to colonise an artificial coastal defence?

Led by Dr Ruth Callaway, the Mumbles Sea-Hive project tested different structures directly on the existing sea wall. The focus was not only on the visual effect of the surface, but also on its ecological performance.

Hexagonal concrete panels with different reliefs, heights and orientations were tested. Some structures ran horizontally, others vertically or diagonally. The position on the wall also played an important role, as the surfaces were covered by water for different lengths of time depending on their height.

Over a period of around twelve months, researchers monitored which surface structures were most readily colonised by marine organisms. An important partner during the trial phase was our customer Cubex, who manufactured all UHPC hexagonal tiles for the test site. Using our PU Elastomer A60, Cubex also created a number of bespoke surface patterns, including oyster- and coral-inspired designs, alongside the scientifically developed test structures. These custom-made patterns demonstrated at an early stage how functional performance can be combined with creative design, highlighting the potential of individually textured concrete surfaces for ecological coastal protection projects.

The local community also played an active role in the project. Residents were able to follow the development of the test panels, share their observations and even contribute to the evaluation process. As a result, the promenade became an open-air laboratory.

The trial phase also attracted special attention through a public presentation on site. A well-known television personality introduced the project during the trial stage, making ecological coastal infrastructure accessible to a broader audience.

The new sea wall follows a clear structure. In the upper section, the construction protects against waves, storm surges and overtopping. In the lower section, structured concrete surfaces define the visual appearance.

In the areas regularly exposed to tides, moisture and marine life, the profiled surfaces create valuable microstructures. Recesses, edges and irregular reliefs offer grip, shade and protected zones.

As a result, the coastal wall not only fulfils its traditional protective function but also becomes a potential habitat. 

The project was complemented by another formliner: Via Aurelia.

At the top of the wall, this texture runs along the entire promenade. Over a stretch of around 1.2 kilometres, it creates a calm, continuous design horizon.

While Kerry in the lower section reflects the rough, rock-like coastal landscape and supports ecological functions, Via Aurelia gives the upper wall area a clear architectural line.