Resumo:
Floods and inundations are a reality in many cities in Brazil due to intense urban
expansion and disorderly land occupation. To quantify surface runoff in urban
basins, understand its hydrological behavior and assess the causes of flooding,
hydrological models can be used. These models help in the planning of urban space,
in the evaluation of drainage control measures to be implemented and subsidize
decision-making. In this context, the present work aimed to evaluate the
applicability of the SWMM hydrological model (Storm Water Management Model)
for the analysis of flooding in urban neighborhoods in the neighborhood in relation
to the minimum data necessary for this type of study. For this, a case study of the
Vila Rubens neighborhood, in Itajubá/MG, will be carried out to analyze the main
causes of flooding and the effects of adopting some sustainable measures to control
urban drainage. First, the delimitation and diagnosis of the study area were carried
out. The defined hydrographic basin was characterized in relation to its physical
and hydrological aspects. The study of intense rains was elaborated through
analysis of the frequency of maximum precipitations, the rain disaggregation in
sub-daily quantiles was carried out by the Torrico method and the temporal
discretization by the Huff method to obtain the design rain for return period of 2, 5
and 10 years. Surface runoff was estimated using the CN-SCS infiltration method
and the Dynamic Wave model for hydraulic transport. The current scenario of the
basin was simulated and then some scenarios were defined with LID (Low Impact
Development) control measures. For the three return times, the critical rainfall
duration obtained in the current scenario was 30 min and the sub-basin
corresponding to the Morro Chic neighborhood was the main contributor to the
runoff portion. The adoption of LID measures, mainly at the source of the problem,
contributed to the minimization of flooding. Despite the results of the
measurements, the location of the basin, which is located in a floodplain, on very
flat terrain, must be considered. The large amount of necessary input data and the
uncertainties in the determination of some of them were difficulties encountered.
Faced with these uncertainties, it can be said that the validation with the residents
was fundamental in the application of the SWMM model to areas with little data
that feed the model and without measured flow data for calibration and verification.
The SWMM model proved to be suitable for this study and can be used as an urban
planning tool.