Water balance estimation of river basins using an innovative hydrological techniques

Abstract

The article proposes a novel scientific approach to evaluating the water balance of river basins. The study takes into account the influence of numerous factors affecting water balance, including climatic variables, land cover, and morphometric characteristics of the area. Over the long-term average period, the water balance of river basins is considered as the distribution of atmospheric precipitation into three components: surface runoff, subsurface flow (underground feeding of rivers), and actual evapotranspiration. A comparison between observed data and newly calculated water balance components for more than 70 river basins with diverse physical and geographical conditions shows minimal discrepancies. In 71 cases, the calculation error was within 10%, and in 29 cases, it slightly exceeded this limit. As a case study, the water balance components of the Goychay River Basin for the period 1999–2024 are presented. During this period, out of the total precipitation (587.3 mm), 117.2 mm (19.9%) contributed to surface runoff, 94.9 mm (16.2%) to subsurface flow, and the remaining 375.2 mm (63.9%) to actual evapotranspiration. The proposed approach stands out for its rapid computation mechanism and high accuracy, underscoring its relevance and practical applicability.