Hydrodynamic modelling of a regulated Mediterranean coastal lagoon, the Albufera of Valencia (Spain)

Coastal lagoon hydrodynamics are strongly influenced by sea water exchange, especially when the connection between the lagoon and the sea is artificially regulated. These situations increase the complexity of the hydrodynamic regime, requiring the use of numerical models to understand their behaviour. Traditionally, one-dimensional models have been used, although in recent years, the development of two-dimensional shallow water models and advanced numerical techniques have increased notably. However, most of the existing bi-dimensional models consider the connection to the sea as a boundary condition, and they do not take into consideration the sea-lagoon exchange. In this paper, a fully two-dimensional hydrodynamic model of a heavily regulated coastal lagoon, which includes the artificial connection with the sea, is presented. The model allows the characterization of water level variation in the lagoon, taking into account the combined effect of different forcings. This model consists of two hydrodynamic modules: a long wave module (two-dimensional depth-averaged) which includes the analysis of a system of sluice gates, and a wind module (quasi three-dimensional). The model was successfully calibrated and validated with real data, showing its ability to accurately describe the hydraulic dynamics of regulated coastal lagoons.