SA / 2D Connection problem

[zatmenie13]

Hi guys. Weird problem appeared. There are 3 2D areas that I connect using SA / 2D Connection. A total of 9 connections are obtained. When starting the model, an error appears on half of the connections:
There is an inconsistency on the information about flow direction over this structure. The positive flow convention for a structure is for stationing to increase going from left
to right while looking downstream (like XS’s). The centerline’s direction is opposite what would be expected from the user entered ‘From’ and ‘To’ connected storage
areas (or 2d flow areas). To fix this problem, you need to either:
Swap the ‘From’ and ‘To’ connected storage area (2d flow area) names.
or
Reverse the centerline stationing (and likely the weir profile data as well).

The model was built according to all the rules, in the connection parameters the correct flow direction is indicated from where to. The central line has a direction from left to right when viewed from the upstream towards the downstream. I am using HEC-RAS 6.1 version

[steven crisp]

Did you ever find a solution to this? My model was working fine until I updated my weir/dam and now I am getting this error between my SA/2D connection when trying to compute an unsteady flow analysis.

[alister.hood]

For the sake of others encountering this in future, I also encountered it despite entering data that was all consistent.
It seems the issue was because of the gap I had between the two flow areas. It seems you need to have both flow areas close to the connection. RAS connects them up graphically, and if they are too far away it will snap onto them in the wrong direction.
You can also get this error if you have the connection inside one of the flow areas, although you might just get: “Computed weir stationing on the Headwater side is not increasing, check the structure data (weir stationing and centerline) and 2d mesh in this area to fix this problem.”

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