It doesn’t look like the initial snowpack on an LID is properly accounted in the Routing Error calculation. Attached ZIP features a single catchment with an LID and no rainfall, the only runoff is generated by snowmelt. There are two files: one represents the initial snowpack depth of 220mm (minus 1mm free water) and the other with 210 mm of precipitation at the beginning of simulation (and snowpack depth of 0mm). The Snow Depth hydrographs match, however the routing error for the initial snowpack scenario is 64% compared to 0% for the initial snowfall scenario.
SnowFallingOnLIDs.zip
It doesn’t look like the initial snowpack on an LID is properly accounted in the Routing Error calculation. Attached ZIP features a single catchment with an LID and no rainfall, the only runoff is generated by snowmelt. There are two files: one represents the initial snowpack depth of 220mm (minus 1mm free water) and the other with 210 mm of precipitation at the beginning of simulation (and snowpack depth of 0mm). The Snow Depth hydrographs match, however the routing error for the initial snowpack scenario is 64% compared to 0% for the initial snowfall scenario. SnowFallingOnLIDs.zip