Comparison of Two Hydrodynamic Models of Weeks Bay, Alabama

This paper presents a comparison of two hydrodynamic models of the Weeks Bay sub-estuary (Alabama, USA). One model was developed using the Environmental Fluid Dynamic Code (EFDC). The resulting model was compared to an existing hydrodynamic model (of the same water body) that was developed using the Adaptive Hydraulic modeling system (ADH). Comparisons were performed in terms of predicted water surface elevations in Weeks Bay. The computational grid was created using GEFDC (a mesh generator for EFDC) and NOAA’s coastline and bathymetric data. The results showed that the EFDC model provides comparable water surface elevation (WSE) estimations for five out of seven control points located in the Weeks Bay study area. R

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values for those points range between 0.88 and 0.99. Root mean square error values are shown to be lower than 0.15 m in those cases. For the rest of the control points, R

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values range from 0.73 to 0.87 (RMSE range: 0.2 - 0.35), showing that the EFDC model provides acceptable estimations of WSE when compared to the ADH model WSE output. A finer computational mesh may improve EFDC WSE estimations for Weeks Bay as reported in the literature.