Infoworks - Pipe grade calculator
Pipe grade calculator between US and DS inverts, Ultimately having the ability to calculate downstream or upstream inverts over a long network based on a specified grade from either a DS or US invert level as a starting point.
Brad Pierce commented
This could be implemented as a single value, or better yet, a user-definable table of slopes for various diameters or height/width combinations. That way the user could enter minimum regulatory slopes or better for each pipe/conduit size.