Impact Assessment of Climate Change on the Near and the Far Future Streamflow in the Bocheongcheon Basin of Geumgang River, South Korea

Abstract

Highly concentrated precipitation during the rainy season poses challenges to the South Korean water resources management in efficiently storing and redistributing water resources. Under the new climate regime, water resources management is likely to become more challenging with regards to water-related disaster risk and deterioration of water quality. To alleviate such issues by adjusting management plans, this study examined the impact of climate change on the streamflow in the Bocheongcheon basin of the Geumgang river. A globally accepted hydrologic model, the HEC-HMS model, was chosen for the simulation. By the calibration and the validation processes, the model performance was evaluated to range between “satisfactory” and “very good”. The calibrated model was then used to simulate the future streamflow over six decades from 2041 to 2100 under RCP4.5 and RCP8.5. The results indicated significant increase in the future streamflow of the study site in all months and seasons over the simulation period. Intensification of seasonal differences and fluctuations was projected under RCP 8.5, implying a challenge for water resources managers to secure stable sources of clean water and to prevent water-related disasters. The analysis of the simulation results was applied to suggest possible local adaptive water resources management policy.

Efficiency analysis of best management practices under climate change conditions in the So-okcheon watershed, South Korea

“…The confluence of the So-okcheon watershed's stream with the downstream watershed creates a bottleneck, creating highly conducive conditions for algal blooms. Consequently, the recurrent prevalence of algal blooms in Daecheong Lake has emerged as a significant concern for regional water security (Kim et al, 2021). Hence, the So-okcheon watershed serves as the ideal study site for the implementation of BMPs designed to mitigate nutrient loads.…”

“…The steep slopes within the relatively compact national territory amplify these challenges, as rapid runoff from rainfall events on such slopes accelerates the transport of pollutants into nearby water bodies. Furthermore, South Korea experiences concentrated precipitation, primarily during the summer months of June, July, and August (Kim et al, 2002;Kim et al, 2021). These distinctive characteristics underscore the need for tailored strategies for ecological restoration in such areas, emphasizing the urgency for effective non-point source pollution control.…”

Evaluation of Future Streamflow in the Upper Part of the Nilwala River Basin (Sri Lanka) under Climate Change

“…In this study, a widely used semi-distributed conceptual hydrological model, the HEC-HMS 4.6.1, which was developed by the United States Army Corps of Engineers, was used to simulate the rainfall-runoff processes. This hydrological model was previously used by Kim et al [56], Gunathilake et al [57], and many other hydrologists. The model calibration was carried out at daily time steps for 11 years from 1998 to 2008 in the present study.…”