A numerical study of the coastline evolution at the Volturno River mouth
E. Benassai, M. Calabrese, A. Ragone
Dept. of Hydraulics and Environmental Engineering, Univeristy of Napoli
''Federico II'', Napoli, Italy
M. Gonella
Med Ingegneria S.r.l., Ferrara, Italy
P. Teatini
Dept. Mathematical Methods and Models for Scientific
Applications, University of Padova, Padova, Italy
ABSTRACT
The Volturno River, whose catchment covers an area of approximatively
5500 km2, is a typical V-shaped valley which meanders its way from
Capua to the coastline, where it discharges through the alluvial deposits
carried down through time. Originally the mouth of the river was oriented
in such a way as to give rise to a slightly cuspidate coastline; during the
last 50 years the river mouth has been receded dramatically. The recession of
the river mouth may be attributed to the various training works along the river,
sediment extraction upstream as well as the hydrodynamic interaction between
wave motion, tides and river currents. The loss of symmetry between the left and
the right banks is mainly due to the coastal defence works built to protect
real-estate bounded by the right river bank.
The shape of the mouth is influenced by two alternating effects: the modelling
of the alluvial deposits by wave action and tides, and the influence of the water
and the sediment discharge from the river. The sediment transport porcessess
actually are chiefly due to the wave motion coupled to longshore / offshore
currents that have stronger effects than the peak river flow.
By using appropriate mathematical models it was possible to study the evolutionary
process of the river mouth taking into account the conditions in which the wave
action prevails against the stream flow and vice versa.
