Units

EFDC uses the metric system to define the space and concentration variables. Meters are used for all of the length related parameters and g/m³ are used for concentrations, with the exception of salinity (kg/m³) and toxics. For toxics, the units must be consistent between concentrations and the water column and sediment bed sorption parameters. Generally, these are in mg/m³ or g/m³.
The internal EFDC time units are in seconds. For EFDC, most of the input files can use any units along with a conversion factor to change the input units to seconds. EFDC+ Explorer has fixed the user input units to days. All of the timing input should be in days and EFDC+ Explorer generates the necessary conversion factors to seconds.