Sediment

Activate the Sediment Module

The Graphical User Interface (GUI) for the Sediment module in EE can be activated from the EFDC+ Modules, as shown in Figure 1.

Figure 1  EFDC Modules Form - Sediment Transport Option.

EFDC+ supports two separate approaches for sediment transport computations: (1) Original EFDC Sediment Transport (Hamrick, 1996), and (2) Sediment Dynamics Algorithms developed by Ziegler, Lick, and Jones (SEDZLJ) (Ziegler et al., 2000; Jones and Lick, 2001; Grace et al., 2008; James et al., 2010).  Both approaches simulate the movements of sediments in the water column, changes in sediment bed properties, and sediment flux between the water column and sediment bed (i.e., erosion and/or deposition) based on flow fields computed by the hydrodynamic module.  Two distinct differences between the two approaches are in the ways they treat cohesive and non-cohesive sediments and the ways they compute erosion rates of the sediment bed.  First, the Original EFDC Sediment Transport option applies separate computation processes for cohesive and non-cohesive sediments, but the SEDZLJ option uses a unified treatment for multiple sediment classes with representative particle sizes (regardless of cohesiveness).  Second, the Original EFDC Sediment Transport option simulates the erosion process using a user-defined constant erosion rate parameter that is assigned to entire model grid cells, whereas the SEDZLJ option is capable of applying spatially varied erosion properties by employing site-specific erosion rate data acquired from SEDFlume sediment core tests.