Understanding base flow and its implications on flooded/lost volumes

Hi all,

I'm fairly new to InfoWorks and am trying to assess the impact of various surface water management solutions on flooding using InfoWorks CS. A couple of the options I am considering include constructing overland channels which are quite wide (in an attempt to model water flowing over a road surface). Since base flow is limited to 20mm depth, and the channel is particularly wide and long, the volume of water appears to be significant. This option also appears to fix my flooding problem (with a channel depth of only 21mm).

From my understanding the base flow is a depth applied to each link. Just wondering whether this has any impact on the amount of water going into/out of a node? And whether the baseflow applied is assumed to be "real" i.e. does the model allow the channel to fill from the bottom of the link or does it begin filling from a depth of 20mm? (this seems improbable but clarification would be useful).

Help would be much appreciated.

Thanks in advance,

Abbie