HYDRODYNAMIC CHARACTERIZATION OF MARAJÓ BAY WITHIN THE AREA OF INFLUENCE OF THE BARCARENA INDUSTRIAL DISTRICT

The hydrodynamic characterization of Marajó Bay was conducted through computational modeling using SisBaHiA®, aiming to identify tidal types and amplitudes, flood and ebb slack waters, high and low tides, the relationship between flow velocity and water level elevation, and phase differences. The hydrodynamic characteristics of this estuarine system are influenced by astronomical forcings, local environmental features, bathymetry, bottom shear stress, morphology, and river discharge. Methodological activities included the definition of the modeling domain, finite element mesh discretization, and 2DH hydrodynamic modeling. To identify fluvial and marine influences on the hydrodynamic behavior of Marajó Bay, five control stations were established along an area extending in the NE-SW direction. The simulated scenarios corresponded to the periods of highest and lowest rainfall in the region for the year 2021 (March and October, respectively). The results demonstrate that the region presents a predominantly stationary semi-diurnal tide, with phase differences and ebb durations increasing upstream of the modeling domain. Maximum velocities did not exceed 1.15 m/s. The hydrodynamic patterns identified in the study area are of paramount importance and can be utilized to assess potential environmental impacts in the aquatic system caused by the discharge of industrial effluents from the Barcarena Industrial District (DIB) or sanitary sewage from communities and urban centers located along the margins of this vital water system in Northern Brazil.