Regional Flood Frequency Analysis in the Doce River Basin and Coastal Regions in Espírito Santo State, Brazil – Evaluation of the Performance of L-Moments Approach

Abstract

Objective: To evaluate the performance of the Index-Flood methods using L-Moments when analyzing the regional flood frequency.   Theoretical benchmark: The maximum stream flows estimation is relevant for projects and reduction of flood impacts. However, hydrologic regionalization methods are usually employed due to the absence of maximum stream flow data. In this context, it is relevant to understand the methods performance of regional analysis available.   Method: Regional flood frequency analisys in the Doce River basin and in basins located predominantly in the state of Espírito Santo by the Index-Flood methods, using L-Moments, direct multiple regression and Dimensionless Curve.   Results and conclusion: The Index-Flood method using L-Moments presented better results than the other methods of regionalization evaluated. Changes in stream flow series and configuration of homogeneous regions did not alter significantly the results obtained with the Index-Flood method using L-Moments.   Implications of research: Improvement of the process of regional analysis of flood frequency.   Originality/value: Consistent analysis of the frequency of occurrence of floods, a recurrent socio-environmental problem aggravated in the context of climate change, constitutes a relevant advance for the management of water resources and has the potential to assist in the establishment of public policies aimed at territorial planning.