I am trying to model a design and I am coming to the conclusion StormCAD cannot truly, accurately model it. Wanted to get other's opinions who may be more experienced with the program/design to make sure my assumption is correct and whether the modeling capabilities is enough to ensure/vet the design.
We are dealing with a ECA-type slope and want to capture the 100 year storm event and get it out of the area as soon as possible. The slope varies from 50% to 75%. We designed a bench at the toe of the slope of ~5 foot width, flat, with several area drains connected with a 6" perf pipe about 2.5 ' below grade. The slope bench is also lined with an impenetrable ditch liner as we do not want water to infiltrate. "Drain" set at 3" above grade. The goal is to have the water drain into the gravel bench into the perf pipe before it is conveyed to our SD connection. This bench is up against the Building/landslide-designed wall.
How it was modeled was with catchments going to each "drain" with the conduit connecting and conveying the flow to our SD connection. However, the model doesn't take into consideration that the conduit is perforated and is the first line of drainage before the inlet. The model shows our design gets the water out via drains and conduit, but is it acceptable given the true design intent?