In Ploemeur, a project to reinforce the Lomener seawall and protect the coastline
On the Breton coastline, breakwaters play an essential role. They protect ports, infrastructure, and maritime activities from waves and storms.
In Ploemeur, in the Morbihan area, the Maritime and River Works teams worked for six months to reinforce the Lomener port breakwater. The goal of this project was to strengthen the structure so that it can better withstand marine conditions and provide long-term protection for the coastline and port infrastructure.
Carried out in an environment exposed to winds and heavy swells, the works had to continuously adapt to tidal cycles and weather conditions.
Why reinforce a maritime breakwater?
Over time, breakwaters are subject to significant stress. Waves, storms, and erosion can weaken the joints between stones or damage certain parts of the structure. To ensure their effectiveness, regular maintenance and reinforcement are therefore necessary.
Reinforcing a breakwater improves its resistance to harsh marine conditions while extending its lifespan. These works also help protect port infrastructure and limit coastal erosion—both major challenges for coastal regions.
A maritime project shaped by the tides
Working on a coastal breakwater requires adapting to a particularly demanding natural environment. In Ploemeur, teams had to organize their operations according to the tides, which determine when certain areas of the breakwater are accessible.
The project also took place in a confined workspace exposed to winds and swells. In these conditions, careful planning and team coordination are essential to ensure worker safety and the smooth progress of the works.
Specific techniques used to reinforce the breakwater
To strengthen the Lomener breakwater, several techniques specific to maritime works were implemented. Over nearly 300 meters, concrete was pumped underwater to consolidate certain weakened areas of the structure.
Professional divers were also involved to inspect the submerged sections of the structure and carry out repair operations directly underwater. At the same time, the joints between the stones of the breakwater were restored to improve the overall watertightness and solidity.
Finally, injections were carried out within the core of the breakwater to enhance its stability and extend the structure’s lifespan in the face of marine conditions.
A project serving the Ploemeur area
The Lomener breakwater plays an essential role in protecting the port and coastline of Ploemeur. By reinforcing this structure, the project helps secure port infrastructure and protect maritime-related activities.
These works also contribute to preserving the coastline against storms and coastal erosion, phenomena that affect many coastal regions.
A project open to young people in the local area
Beyond the technical challenges, this project also provided an opportunity to showcase maritime construction professions. The teams welcomed students from the Rennes Civil Engineering Institute of Technology (IUT) as well as young people from Ploemeur.
These visits made it possible to share on-site experience, present the techniques used, and concretely demonstrate the professions involved in building and protecting infrastructure.
A collaborative effort involving multiple local stakeholders
The Lomener breakwater reinforcement project was carried out for the Morbihan Department, with Compagnie des Ports du Morbihan and FR Environnement Nautique serving as project managers.
The success of the project relied on the collaboration between these various partners, as well as on the commitment of the teams mobilized on site throughout the duration of the works.
The Lomener breakwater reinforcement project in Ploemeur highlights the importance of maritime works in protecting coastal areas. Thanks to the expertise of the teams and techniques adapted to the marine environment, this essential structure is now better equipped to withstand maritime conditions and continue providing long-term protection for the coastline and port infrastructure.
Crédit photo : FlyUpDrone
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Serving local authorities and stakeholders, Colas teams design and deliver development projects tailored to the specific characteristics of each region. From coastal protection to port infrastructure, our expertise also extends to maritime and river environments.
