Dimensioning of reservoirs for semiarid regions using synthetic series

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.

摘要：流域河流水文监测数据的缺失，会影响调节水库库容的估算——而调节水库对于保障季节性需水至关重要。本研究旨在评估基于径流量合成序列（SS）的多种方法在巴西热基蒂尼奥尼亚河流域调节水库库容设计中的表现。本研究分别采用是否结合重现期的两种方式，结合不同的长期平均径流量、实测径流合成序列，以及由米纳斯吉拉斯州水资源管理局（Instituto Mineiro de Gestão das Águas）开发的径流区域化方法得到的估算数据，对水库库容（RC）进行了估算。将所得结果与基于调节曲线区域化法和水库库容区域化法得到的水库库容进行对比后发现，结合重现期与合成序列的方法表现更优，其高估均值和低估均值分别降低了25%和15%，且估算值更接近基于实测径流序列得到的结果。因此，在热基蒂尼奥尼亚河流域无河流水文监测的区域，采用基于合成序列的水库库容估算方法是切实可行的。