Ice cover code

In the EFDC source code I am wondering what is the name of the module which contains the calculations for ice cover? I am trying to add a constant layer of ice cover to a river reach, and would like to understand how the source code does this.

There is no separate module for ice and no computations for ice at this stage. EFDC just reads an ice cover file, ICECOVER.INP. You can look at how ISICE is handled in calheat.f90 and caltsxy.f90 for details.