Pond with sloping base

[watershedc]

Hi group,

I'm trying to model an open channel as a pond structure, since I would like to account for exfiltration via an under drain along the swale, and a raised outlet structure at the discharge point of the channel. I notice that it is possible to model a horizontal cylinder with a sloped base, however, I'm not sure how to account for the slope of the channel (3%) using the Prismatoid Storage definition. Any suggestions?

 

[TerryScan]

I would probably use custom stage-storage and provide input at intervals small enough to describe the storage.