Abstract: 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 depthaveraged)
which includes the analysis of a system of sluice gates, and a wind module (quasi threedimensional).
The model was successfully calibrated and validated with real data, showing its ability to accurately describe the hydraulic dynamics of regulated coastal lagoons.