HEC RAS unsteady flow adding storage area
HEC RAS unsteady flow adding storage area
(OP)
I am trying to run a dambreach model and need to attach a storage area to the upstream end of reach/cross section.
I have a sample problem that is already set up that way. The storage area editor shows a storage area - cross section connection.
I have tried several colleagues and no seems to know how to do it.
Any ideas?
I have a sample problem that is already set up that way. The storage area editor shows a storage area - cross section connection.
I have tried several colleagues and no seems to know how to do it.
Any ideas?





RE: HEC RAS unsteady flow adding storage area
I assume you're trying to do a level-pool breach routing, i.e. the storage area defines the breached reservoir. HEC-RAS is river model designed for dynamic pool routing where the reservoir is defined using cross-sections. One way around this is to create a "dummy" dam immediately downstream from the real dam. The "dummy" dam is a lateral levee that connects the storage area to the channel, and is the one that is set to breach. The real dam, defined in the stream channel, is merely there to prevent upstream flow.
If this technique isn't acceptable, and you must do level pool routing, your next option would be BOSS DAMBRK. But DAMBRK is a rather pricy proprietary program. Another option would be to set up the reservoir in HEC-HMS, perform the dam breach, and import the resulting breach hydrograph to HEC-RAS as the upstream inflow hydrograph. Only define the channel downstream of the dam. The breach methodology is the same in both programs.
RE: HEC RAS unsteady flow adding storage area
I have a working sample model where the SA is connected to the reach..(no lateral structure) When I asked the individual that set up the model..he said that he thought he dragged the reach to the SA. I tried that ..it didn't work
now I guess I'll try adding points to a reach and see if I can drag it to the SA.
I usually run the DAMBRK model but my client wants this one in HEC RAS so they can graphically see the dam breach.
I will attach the model where the area is at the top..see if you can figure it out.
Thank you so much for your reply!
RE: HEC RAS unsteady flow adding storage area
RE: HEC RAS unsteady flow adding storage area
RE: HEC RAS unsteady flow adding storage area
RE: HEC RAS unsteady flow adding storage area
RE: HEC RAS unsteady flow adding storage area
rt clicked node..nothing
lft clicked node..nothing
unchecked the move object and then clicked the node..also nothing
am I missing a step?
RE: HEC RAS unsteady flow adding storage area
RE: HEC RAS unsteady flow adding storage area
I cannot thank you enough. While I have been trying to make this work, I have started entering info into HEC-HMS in order to create a breach hydrograph which I will import into my HEC RAS model incase the HEC RAS dambreach doesn't work.
I have entered all the information for the reservoir node but the dambreach icon is not coming up...any suggestions?
RE: HEC RAS unsteady flow adding storage area
RE: HEC RAS unsteady flow adding storage area