Coastal Protection and Defence of the Praia da Vitória Urban Waterfront
bluemetrics developed the conceptual and preliminary design and assessment of coastal protection solutions for Praia Grande, located in Praia da Vitória (Terceira Island, Azores), with the objective of mitigating coastal erosion, wave overtopping of the urban waterfront, and the recurrent siltation of the marina access channel.
The main objectives of the study were:
- Enhance the protection of the seawall and urban waterfront against wave action;
- Reduce the occurrence of wave overtopping and coastal flooding;
- Promote the morphological stability of Praia Grande beach;
- Reduce sediment transport towards the marina entrance and navigation channel;
- Ensure the navigability and operational performance of Praia da Vitória Marina;
- Prioritise sustainable coastal engineering solutions based on the beneficial reuse of dredged sediments and geosynthetic structures.
The proposed solution was based on an integrated coastal engineering approach, combining:
- Beach reprofiling and shoreline reconfiguration;
- Redistribution of sediments obtained from dredging operations;
- Implementation of submerged detached breakwaters using geotextile structures;
- Control of sediment transport in the marina sector;
- Enhancement of beach width and its natural wave energy dissipation capacity.
The study included:
- Hydrodynamic and morphodynamic characterisation of Praia da Vitória Bay;
- Analysis of the wave climate and extreme design conditions;
- Development of conceptual models for wave propagation and sediment transport;
- Assessment of wave transmission coefficients for submerged geotextile breakwaters;
- Hydrodynamic numerical modelling using the SWAN and SWASH models;
- Analysis of wave-induced currents;wave-induced currents);
- Morphodynamic numerical modelling using the XBeach model;
- Geometric design and positioning of detached breakwaters;
- Preliminary assessment of shoreline response, including the potential formation of salients and sediment retention areas.
The study established an integrated technical solution for the protection and enhancement of Praia Grande, combining urban coastal defence with sustainable sediment management and the mitigation of siltation problems affecting Praia da Vitória Marina.
