I am looking for recommendations from experienced users. For cross-pipe analysis of pipes which are not culverts that impact FEMA floodplains, and where HY-8 is invalid due to velocity limitations, would you recommend using HEC-RAS or using HDS-5 Nomographs? Why?
I am using HY-8 for the analysis of existing cross-pipes, trying to determine headwater elevations. The drainage manual i am using lists conflicting limitations for the HY-8 software. In one instance, it is noted that HY-8 should not be used where entrance velocity exceeds 5 ft/s. In another...