Application of EFDC and WASP7 in Series for Water Quality Modeling of the Yongdam Lake, Korea

Abstract

This study aims to test the feasibility of combined use of EFDC (Environmental Fluid Dynamics Code) hydrodynamic model and WASP7.3 (Water Quality Analysis Program) model to improve accuracy of water quality predictions of the Yongdam Lake, Korea. The orthogonal curvilinear grid system was used for EFDC model to represent riverine shape of the study area. Relationship between volume, surface and elevation results were checked to verify if the grid system represents morphology of the lake properly. Monthly average boundary water quality conditions were estimated using the monthly monitored water quality data from Korean Ministry of Environment DB system. Monthly tributary flow rates were back-routed using dam discharge data and allocated in proportion to each basin area as direct measurements were not available. The optimum number of grid system was determined to be 372 horizontal cells and 10 vertical layers of the site for 1 year simulation of hydrodynamics and water quality out of iterative trials. Monthly observed BOD, TN, TP and Chl-a concentrations inside the lake were used for calibration of WASP7.3 model. This study shows that EFDC and WASP can be used in series successfully to improve accuracy in water quality modeling. However, it was observed that the amount of data to develop inflow water quality and flow rate boundary conditions and water quality data inside lake for calibration were not enough for accurate modeling. It is suggested that object-oriented data collection systems would be necessary to ensure accuracy of EFDC-WASP model application and thus for efficient lake water quality management strategy development.

Assessment of Future Climate Change Impact on Water Quality of Chungju Lake, South Korea, Using WASP Coupled with SWAT

“… Review of studies from the past decade in South Korea: Kwak (); Seo and Lee (); Kim and Han (); Park et al . (); Seo and Kim (). …”

Prediction of Chlorophyll-a Changes due to Weir Constructions in the Nakdong River Using EFDC-WASP Modelling

“…The 3D hydrodynamic model, the Environmental Fluid Dynamics Code (EFDC) model was used to consider the changes in hydrodynamic conditions due to the project [11][12][13][14]. Hydrodynamic information, generated by the EFDC model, was linked to the WASP model for water quality modelling [15][16][17][18][19]. Special attention was paid in analyzing a chlorophyll-a (Chl-a) concentration changes or phytoplankton growth dynamics throughout the river.…”