Climate variability and irrigation impacts on streamflows in a Karst watershed—A systematic evaluation

Abstract

This study focuses on a systematic evaluation and separation of El Niño Southern Oscillation (ENSO) induced droughts and irrigation water withdrawal impacts on flow levels using a novel and powerful statistical technique, called JRFit. JRFit procedure was applied to quantify significant differences in streamflows, baseflows, and low flow statistics during non-irrigation (NI) and irrigation (IR) periods associated with ENSO phases. The results indicate that overall streamflow levels have decreased by approximately 20% after the introduction of irrigation in the study area. This study provides useful information to policymakers to devise irrigation water withdrawal policies during La Niña growing seasons for maintaining flow levels in the study area.