Aplicação do SWMM para modelagem hidrológico-hidráulica de uma bacia litorânea no estado do Ceará

Abstract

Lagoa de Jijoca, 290 km from Fortaleza, is a strategic area for tourism in the northwest region of Ceará on the coats of Camocim and Acaraú, between the municipalities of Jijoca de Jericoacoara and Cruz, and it’s part of the Jericoacoara National Park. Thus, tools to help in the management of it’s water resources are extremely relevant. In this scenario, the present work proposes to elaborate a hydrological-hydraulic model in the SWMM of the Jijoca lagoon basin, delimiting the macro-drainage and its sub-basins, estimating the infiltration and runoff parameters, from a supervised image classification of the Landsat-8 satellite for land use and occupation, developed with a GIS tool. The physical characteristics of the lake were estimated through MDE, generating an area-height plot. The applied precipitation was a time series of hourly reanalysis of the ERA5 for 30 years (1990 to 2019). The model was validated through the historical analysis of Google Earth images, converting the lake’s surface area into an equivalent water level, and comparing the values modeled in the same period. The modeling results indicate that the lake presents infiltration losses of the same order of magnitude as evaporation, indicating the importance of evaluating this parameter in small reservoirs. The model, after calibration, presented a Nash-Sutcliffe coefficient of 0.28, when evaluating the tenyear period (2010 to 2019), considering the rainy and dry seasons, the behavior of the water level in the lake, attesting that the model is a better predictor when compared to using the average of the estimated observations from Google Earth in the same period. Thus, the results obtained indicate that the proposed model has the potential to assist in the management of water resources in the region, simulation of scenarios in which there is climate variability or changes in land use, and other hydrological or hydraulic changes.