Dimensioning of reservoirs for semiarid regions using synthetic series

Priscila R Vieira,Fernando F Pruski,José R C Souza

doi:10.1590/1807-1929/agriambi.v24n9p581-589

Abstract

ABSTRACT The lack of fluviometric data for hydrographic basins affects the estimates of capacity of regularization reservoirs, important to meet water seasonal demands. The objective of this study was to evaluate the performance of methodologies based on synthetic series (SS) of streamflow for the dimensioning of regularization reservoirs in the Jequitinhonha River Basin, Brazil. The reservoir capacity (RC) was estimated with and without the association to return period, using different long-term mean streamflow rates, SS from the observed data, and estimated data by the streamflow regionalization process developed by the Instituto Mineiro de Gestão das Águas. The results obtained were compared to the RC obtained in regionalization methods of the regularization curve and regionalization of reservoir capacity. The methods that include synthetic series associated to return period presented better performance, with 25% and 15% lower overestimate and underestimate means, respectively, and estimated values closer to those that considered the observed data series. Therefore, the use of methodologies to estimate RC, using SS was adequate for the locations without fluviometric monitoring in the Jequitinhonha River Basin.

Highlights

Water scarcity occurs mainly due to asymmetry in its distribution, lack of management, and inadequate management of natural resources
The reservoir capacity (RC) was estimated with and without the association to return period, using different long-term mean streamflow rates, SS from the observed data, and estimated data by the streamflow regionalization process developed by the Instituto Mineiro de Gestão das Águas
The RC was calculated by the proposed methodologies for all stations, and was exemplified by the fluviometric stations 54580000 (Figure 4), representative of the other stations

Summary

Introduction

Water scarcity occurs mainly due to asymmetry in its distribution, lack of management, and inadequate management of natural resources. In this context, arid and semiarid regions are severely affected, since they present intense rainfalls concentrated in a short period followed by a long drought period (Martins et al, 2018). The use of regularization reservoirs is an alternative for decreasing losses caused by scarcity and potentialize the use efficiency of water resources, making possible water accumulation during the rainy periods and distribution throughout long drought periods (Wang et al, 2013; Xu et al, 2017). Regularization reservoirs are important to promote a sustainable management of water resources (Li et al, 2010). The adequate dimensioning of these structures requires long-term records of fluviometric data (Kuria & Vogel, 2015), which are incomplete for most hydrographic basins in the world (Loukas & Vasiliades, 2014)

Objectives

Methods

Results