Flow control / storage of run-off 12 hours

[Civil3DGroupies]

I have a storage node in SSA, which I'm using as a pond.  During the rain event the water overflows into this pond.  Once the water is in the pond I would like to retain the water for approximately 12 hours and then after 12 hours it slowly discharges to another channel.  How can this be done in SSA?  I have tried using weirs, orfices, flow splits, etc, but I just don't see a time dependant function in the storage node or options.  In EPA SWMM there is an editor which allows for flow control measures to be inputted.  I don't see anything like that in SSA?

[Charlie.Ogden · Accepted solution]

Are you planning to put a mechanical gate on an orifice controlled by a timer?  ...or do you just need to show that the detention time is greater than 12 hours?  Your description appears to be the former, so...

You can create a Control Rule (under Other on the Plan View tree) that opens an Orifice at a given system time (I think you'd have to tell the rule the actual time to open, which you could get from the Time Series Plot for the pond inflow - unless someone knows a more creative If/then solution to start when the pond starts to fill).  Chapter 10 of the 2015 User Guide describes the format for Control Rules.

Something like this should work:

RULE R01
IF SIMULATION TIME >= 22:00:00
THEN ORIFICE 1 SETTING = 1.0
ELSE ORIFICE 1 SETTING = 0.0

I hope that's along the lines of what you were looking for.