Determination of Flood Areas in the Stream of Flores basin, Bauru - SP (Brazil)

Abstract

The urban occupation model developed in river basins, in particular by the occupation of valley bottoms, brings some severe consequences to the urban model itself. With the waterproofing of the soil, there is a decrease in the infiltration of rainwater, decreases the time of concentration of the basin, causes an increase in the direct runoff and causes a rapid increase in the water levels that flow through the thalweg, a result, many times, in the overflow of water out of the drainage channel or main bed of the water bodies, causing flooding of the riverside areas or secondary bed. In the impossibility of changing the established urban design, knowledge of the areas affected by rain events, allows the urban manager to draw up plans to mitigate the risks to which people are exposed in the occurrence of these extreme events. The objective of this work was to build maps of flooding areas along Avenida Nações Unidas located in the city of Bauru (SP), from the analysis of the flow capacity of the channel that forms the thalweg of the Córrego das Flores basin. Excess flow rates, elevation heights and flooding areas were determined from hydraulic and hydrological calculations using design norms and normative legislation as a reference. The Results showed that even more frequent recurrence rains (TR = 2 years) are capable of causing flooding and offer risks to the population, being aggravated in events of greater intensity.