HEC-RAS: Distances at junctions

[NormanDGutter]

In HEC-RAS, where I have a confluence of a main stream and a major branch, I have a junction. Through the junction editor I have entered the distance from the junction to the two upstream cross-sections, one in each reach. Do I then, when defining those cross-sections, say the downstream distance is 0 feet? Or do you use the distance across the junction. I've done that (i.e. distance across junction AND downstream distance from cross-section to junction), but this seems overly conservative to me. In the junction editor, I have NOT checked the box for calculating friction.

Thanks in advance,
NDG

 

[francesca]

Have you read the bit in the hydraulic reference manual about the way the junction is calculated?