set initial volumes for res and hru types and convert units
ha-m => m3
ha-m => m3
set initial weir height to principal depth - m
use br1 as lag - then compute actual br1 (no option to input actual br1)
calculate shape parameters for surface area equation
only initialize volume and constituents if operational at start of simulation
if not, assume zero volume when dam is built
initialize org-min in reservoir
set initial reservoir org-min to reset for soft calibration
initialize pesticides in reservoir water and benthic from input data
calculate mixing velocity using molecular weight and porosity
initialize pathogens in reservoir water and benthic from input data
calculate initial surface area
initialize salts in reservoir water, from database file (salt.res)
initialize constituents in reservoir water, from database file (cs_res)