Need a Ditch subassembly built off of DaylightBasin2 that has both Alignment and Profile control located at the invert of the ditch (red X below in image).
1.When only an Alignment is used the Foreslope will vary and ditch invert elevation will remain constant
2.When only a Profile is used the Foreslope will project at the constant user specified slope to accomodate the ditch profile elevation.
3.When both Alignment and Profile are used, Foreslope will vary to accomodate the ditch profile elevation.
Basin depth and basin slopes can remain constant.