Author(s): Artur Cerveira Bertone, Eloy Kaviski, Candice Schauffert Garcia, Eloy Kaviski

Linked Author(s): Eloy Kaviski

Keywords: Probable Maximum Precipitation; Probable Maximum Flood; São Francisco River; Spatial Distribution;

Abstract: The determination of the Probable Maximum Flood (PMF) is an essential parameter for major hydraulic projects, as it involves critical decisions regarding safety and cost. The PMF is defined as the conversion of severe meteorological events into a flow and can be characterized as the physical limit of the flow in the basin.
The present study makes the estimation and validation of the PMF at Sobradinho HPP (Hydroelectric Power Plant), the study is part of a project carried out by RHA Engenharia e Consultoria SS Ltda. and commissioned by CHESF. The case study area is located in the São Francisco River Basin, covering 506,000 km². The study divided the basin into three sub-basins – Três Marias, Morpará and Sobradinho - and estimated the Probable Maximum Precipitation for each of the sub-basins. The PMP is obtained using the adapted Hershfield method (BURGER, 2014), despite being a statistical method of obtaining PMP, it takes the characteristics of the basin into account, therefore presenting more accurate results. With the PMP data, the spatial distribution started in one or more sub-basins simultaneously, because in large watersheds the consideration of a constant PMP is unrealistic. Hence, the spatial variability of precipitation must be considered to achieve more realistic results. This approach permitted the obtaining of a PMF consistent with the hydrological and meteorological characteristics of the basin. The study resulted in a method to be used in the São Francisco watershed, being suitable for use in other large watersheds.

DOI: https://doi.org/10.3850/38WC092019-0560

Year: 2019