The Yesa Reservoir (Upper Aragón river, Cental Pyrennes) and its adaptation to the variability of the fluvial regime

Abstract

The management regime (ínflow and outflow) of the Yesa Reservoir, Upper Aragón River, is studied. The reservoir is mainly devoted to supply water for irrigation in Bardenas, between Navarra and Aragón. For this reason, the reservoir management tends to reach the maximum volume of water in May, in order to release relatively high flows in summer. The filling occurs since October, especially with the high autumn and spring discharges. Three management patterns have been identified. Such patterns are not randomly distributed in time, but they have prevailed in different periods since the construction of the reservoir, showing the occurrence of changes in the fluvial regime.