SSA - Tailwater Condition using Rational Method for stormsewer evaluation

[carlirwin3430]

Can someone help me with a tailwater issue using SSA and the Rational Method for the evaluation of a small stormsewer system (~7 inlets).  At the outfall I have added a fixed tailwater condition which is higher than the crown of the receiving pipe.  For some reason during the evaluation the Max HGL only gets as high as the crown of the outfall pipe, even though I have set the tailwater conditon 1 ft. higher. 

If someone could help me out I would greatly appreciate it.

Thank You,

Carl

[Brian1]

Attached is Carl's data file in spf format

[fcernst · Accepted solution]

help me with a tailwater issue

Are you using Dynamic Wave rotuing?

[wangshenyi]

I tried the model using Dynamic Wave rotuing. The result is much over the design HGL. I tried the different project by using Dynamic wave routing, all of the result are much different with kinematic wave. I even use Stormcad to Calculate the same model. The StormCad can get acceptable result, but Dynamic wave routing wass not. Is there a setting problem?

[crc296]

Did you ever get it to work properly? I am having the same issue with a tailwater condition. Any information is greatly appreciated. Thank you.

[Matt.Anderson]

Can I say - don't?  

Even if you manually push that tailwater into all nodes - you are not going to get a result that mimics a standard step calculation that you expect.  

It's the wrong tool.