Tidal lagoons have the potential to be used to protect coastal communities and manage and lower the risk of flooding. The lagoon walls provide a more sheltered environment, reducing the risk of overtopping and offering the potential to manipulate water levels at times of surge. By artificially maintaining water levels at low levels, lagoons could also play a part in reducing the risk of flooding from rivers.

The design and location of lagoon walls need to be carefully considered to ensure that they do not increase flood risk elsewhere by altering existing water levels or wave climate – e.g. reflecting waves and potentially causing coastal erosion or flooding in areas that were previously not at risk.

Tidal Lagoon Cardiff

The Severn Estuary (Mor Hafren in Welsh) and the Bristol Channel have various sources of flood risk and related hydrological issues. There are a wide range of Flood and Coastal Erosion Risk Management (FCERM) assets and natural features that are managed to control these risks. The over-arching objectives of the flood risk and hydrology topic are to minimise the negative impacts and maximise the positive impacts of the Project during the construction, operation and decommissioning phases. Flood risk objectives have to be considered in the round against other possibly conflicting objectives. Receptors relevant to the hydrology and flood risk topic include people, property, infrastructure and the environment, including protected sites and species. In addition to a review of existing baseline data, numerical models of the rivers within the study area will also be assessed, with the potential for additional data collection of the broader area if required.

Case Study

Tidal Lagoon Plc

E: Info@tidallagoonpower.com

T: +44 (0)1452 303892

A: Pillar & Lucy House
Merchants Road
The Docks

Tidal Lagoon (Swansea Bay) Plc

E: Swansea@tidallagoonpower.com

T: +44 (0)1792 274006

A: 3rd Floor, Room 3.3.4
Civic Centre
Oystermouth Road
