Flap Valve on culvert in main channel. HEC RAS

[wschluter]

I am trying to model a river section that includes a Flap Valve on a box culvert in the main channel. There are two openings with flap valves.
All I want is positive flow only.

I found that this can be done for lateral structures and was wondering if there is a way to do this for the main channel.

I am using HEC RAS 4.0 Beta.

Many thanks.

[AbNormal_Depth]

There is no backflow option for a culvert/bridge structure.
You must use an inline structure with the gate option and use the gate rules to close the gate when the Tailwater >= Headwater.