Comparative Analysis of Hydrological Dynamics and Data Quality in Rainfall-Runoff Process Using WETSPRO: Case Studies from Belgium and Iran

Accurate flood simulation and forecasting in various catchments is a hot issue in hydrology. Rainfall-runoff modeling, one of the most intricate and important hydrological processes, is essential for accurate flood forecasting and effective water resource planning and management. Given that many rainfall-runoff models rely on filtering flow into baseflow, interflow, and overland flow components, the quality of these filtered outputs significantly impacts the accuracy of modeling. The study demonstrates the effectiveness of the Water Engineering Time Series PROcessing (WETSPRO) tool in separating quick and slow flows, extracting peak-over-threshold (POT) events, and evaluating tool performance on extreme events across two distinct catchments with differing geographical and climatic characteristics. The objective is to investigate the influence of data accuracy, data quality, and basin hydrological and geographical characteristics on the tool’s performance. To this end, daily river discharge data from the semi-arid Gorganrood River basin in northern Iran and the temperate Kleine Nete Basin in northeastern Belgium were utilized. The analysis of flow separation in two basins demonstrated that the tool’s precision is dependent on the quality of the input data. The Kleine Nete Basin, with shorter filtering periods, revealed rapid flow dynamics, while the Gorganrood Basin, requiring longer intervals, showcased slower responses and prolonged water retention. Additionally, the Kleine Nete Basin, with its more frequent quick flow events (66 POTs), is highly susceptible to flooding. In contrast, the Gorganrood Basin showed more intense and fewer quick flow events (52 POTs), indicative of a less dynamic hydrological regime. These findings align with the respective catchment sizes, climatic conditions, and land use. The results highlight WETSPRO’s versatility through its effective application to data from the Gorganrood Basin. This capability validates the tool's potential as a universal tool for hydrological modeling, capable of precisely analyzing different climates and geographical regions.

Comparative Analysis of Hydrological Dynamics and Data Quality in Rainfall-Runoff Process Using WETSPRO: Case Studies from Belgium and Iran Keywords:

Extreme events analysis , Rainfall-runoff modeling , WETSPRO , Kliene Nete , Gorganrood