Xitaizi Experimental Watershed dataset, Beijing, China

Bimodal runoff behavior, characterized by two distinct peaks in flow response, often leads to significant stormflow and associated flooding. Understanding and characterizing this phenomenon is crucial for effective flood forecasting. However, this runoff behavior has been understudied and poorly understood in semi-humid regions. In this study, we investigated the response characteristics and occurrence conditions of bimodal hydrograph based on the hydrometric and isotope data spanning 10 years in a semi-humid forested watershed in North China. In this dataset, we provide essential observational data from the Xitaizi Experimental Watershed in North China, including information on rainfall, groundwater levels, soil water content, streamflow, and isotopic measurements (δ18O).