The coastline of NE Pará presents a configuration cut and a large number of estuarine systems, very active with amplitudes of tide between 5-7m.In this region, is inserted the estuary of the river Maracanã - estuary of coastal plain and the type and mixed - with a length of 101 Km from igarapé the tube to the island of Cumaru. The profile of this is typically meandrante, low slope that allows runoff, and allows a pattern of drainage with large amount of water in several directions and an order of flow of 103 to 104 m3 s-1.This estuary likely a result of the system of macro-tides (> 4m), the semi-diurnal nature, with winds of influence (average of 6 m / s) and the tidal currents (mean of 69.53 cm / s). The climate is the type Am (Tropical Wet), which is characterized by being warm and humid (Climate Equatorial Amazon), with temperature between 25 ° C and 28 ° C and rainfall of 2,500 mm / year to 3,000 mm / year, and two distinct periods, a dry (June to November) and another rainy season (December to May). The work was aimed at the implementation of the hydrodynamic modeling the movement of the estuary of the river Maracanã (NE Pará), using as a modeling tool (Program Design SisBAHIA - Base Hidrodinâmica Environmental System), based on interpretation of the data collected in the field and experimental studies conducted in the laboratory. The methodological procedures consisted of three basic steps: bibliographical survey, work of field and laboratory. In the field, were performed: (1) a survey of semi-ecobatimétrico detail, employing is a Ecossonda DGPS / PLOTTER / SONAR FURUNO GP-1850 F, which were made transects ecobatimétricos cross-sectional and longitudinal in the estuary during the flood tide, ( 2) measurement of currents, tidal, to obtain measures of intensity and direction of currents in a point (00 ° 45187 'S and 47 ° 26712' W), over a period of continuous sampling of 8 days (preamar e) (baixamar 04/02/07 to 11/02/07), covering sizígia. To this end, it was used a Correntógrafo Falmouth Scientific 2D-ACM, (3) the monitoring of the vertical tide was based Marégrafos Orphimedes Brand OTTHidrometrie, which recorded the water level at the same time, near the mouth and the inner part of the estuary, for a period of 8 days continuous every 20 minutes. In the laboratory: (1) the data processing environment ecobatimétricos in Excel for correction in relation to the level of tide. Still, the Surfer was used for scanning the data input for the hydrodynamic model of the Program Sisbahia, (2) time series of the level of current
and tide were subjected to routine data processing environment developed in Excel (3) For flow was conducted an estimate based on simple and rational.The data were then processed for analysis: (1) In implementation of the model, were gathered all the data collected in the study area and these data were supplied to the model within a predefined area, (2) For calibration of the model Adjustments were made in an attempt to merger of the data collected in the field and model, (3) the validation of the model, which was the accuracy of the results of the computational model in relation to its purposes, and the natural system that it represents, in order to reproduce the actual phenomena. Then put up the model pra "run", that is, the model will generate scenarios of ebb tide, flooding, and squaring sizígia. With this, could itself describe the patterns of movement of estuarine river Maracanã and understand the aspects of their complex hydrodynamics. Thus, it is obtained, maps featuring patterns of current averages upright over a cycle of the tide sizígia and quadrature (half ebb tide, half flood tide, estofa of preamar and estofa of baixamar). It was observed that during the tides of sizígia, the speeds are higher if compared with the tides, squaring. The geometry of the estuary is responsible for restricting the penetration of coastal waters and help to raise the tide inside of it. The results generated by the model were not equal to those measured in the field, because of the complexity of the area and the amount of data acquired.
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