Author(s): Enrique Gonzalez Pena; Fernando Mera Lopez; Jeronimo Agudo Puertas
Linked Author(s): Jerónimo Puertas Agudo, Enrique Peña González
Keywords: Ulla estuary; Hydrodynamics; SMS numerical model; Dredged channel; Environmental impact
Abstract: The geography of Galicia, in the northwest of Spain, is full of river mouths that interact with the sea in big bays. In the case of the Ulla´s river, this estuary is more than 40 km long. Recent civil works developed in surrounding areas induced morphological changes in this particular coast line, due to the alteration in the mechanics of sediment transport. Also related, the salt water intrusion regime is being modified, so the ecosystem and the shellfish survival of this region is threatened. This paper shows the results obtained computing with the software SMS to determine depths and velocities in the critical shellfish collecting zones, where seawater must be always present. Field data has been registered including velocities in seven points located in two transversal sections of the river mouth. Different alternatives have been tested to find a solution to this particular but essential problem, including a dredged channel of 1.5 m height. This channel is defined in order to convey the majority of the river water in high flow events. Flooding and velocity maps of the area show the evolution of the hydraulic variables in unsteady conditions.
Year: 2004