Hydrological dynamics of the shire river: Insights from baseflow and recession analysis

Abstract

The Shire River, a vital waterway in Malawi, plays a pivotal role in the country's economy, serving as a source of electrical power and irrigation for surrounding communities. This study investigates the hydrological dynamics of the Shire River by examining its flow components and the influence of baseflow under varying climatic conditions. Through meticulous baseflow separation using the Eckhardt recursive digital filter and recession analysis, Lake Malawi emerges as the primary contributor to the river's baseflow, sustaining approximately 80%–82% of total flows annually of which about 78% is contributed during wet seasons. Moreover, an inverse relationship between baseflow and rainfall is observed, highlighting the significance of baseflow augmentation during drier periods. Baseflow analysis of wettest and driest years further elucidates precipitation's impact on baseflow fluctuations, emphasizing the intricate interplay between precipitation patterns and baseflow dynamics. Therefore, to ensure the sustainable management of the Shire River, it is crucial to implement policies that support the conservation of groundwater resources and the efficient allocation of water during varying climatic conditions. Overall, this study provides valuable insights into the hydrological processes of the Shire River, contributing to enhanced understanding and sustainable management of this essential water resource.