Author(s): J. García-Alba; J. F. Bárcena; A. García; C. Álvarez
Linked Author(s):
Keywords: Near field; Far field; Coupling approach; Urban and industrial discharges; Integrated modelling; Estuary; Sewage system
Abstract: The carrying capacity principle is based on the idea that the environment can cope with certain pollutant loads. As long as the carrying capacity of a water system is not exceeded, no adverse effects will follow. According to this idea, the replacement of the Suances Waste Waters Treatment Plant (WWTP) required to determine the level of treatment necessary for the new facility considering the capability of the Suances Estuary to receive the new pollutant loads without impairing the water quality. For this purpose, several discharges coming from the sewage system and the industries of the study area have been taken into account. Firstly, a comprehensive compilation of information about the topography and bathymetry; the hydro meteorological and water quality data; the sewage system and industrial discharges characteristics; and the environmental regulations was undertaken. Secondly, the study of the evolution of the pollutant concentration introduced by all discharges has been performed with the proposed methodology integrating the results of several numerical models in a continuum, i.e., from the precipitation on the river basin with a hydrological model, through the estuarine water circulation with a hydrodynamic model to the evolution of pollutants with a three-dimensional far-field model. Thereby, a three-dimensional hydrodynamic model was calibrated and validated to generate the physical forcings for both transport and mixing models. Before allocating the new WWTP discharge, the hydrodynamic model has been used to evaluate the three-dimensional behaviour of the estuary in order to select the best location for the discharge point of the new WWTP. Finally, two far-field models for organic and bacteriological pollution were calibrated and validated to study the evolution of the urban and industrial discharges in the estuarine area and determining the final level of treatment of the new WWTP.
Year: 2016