Development and applicability assessment of 1-D water quality model in nakdong river

Abstract

Nakdong River passes through many urbanized cities, industrial complex areas, and water intake stations. Recently eight multipurpose weirs are constructed in the middle of the river. therefore the proper water quality management is crucial in this region. Reviewing existing model for hydraulic and water quality analysis, none was found able to reflect the features of the Nakdong River accurately. This study developed 1 dimensional hydraulic and water quality analysis model, where a stable hydraulic analysis is achieved by considering fixed and movable weirs as internal boundary conditions to reflect low flow conditions and irregular channel cross-sections, and the results are then used to construct a water quality analysis model. A sensitivity analysis is performed to review the proper range of parameters for the proposed model, while the applicability and reproducibility are reviewed in comparison to the EFDC model. As a result, the proposed model showed better results than the EFDC model for the hydraulic analysis, while the predicted water quality results were comparable to the two models, although the proposed model showed a high applicability due to its short simulation time.