Bentley Product:: SewerGEMs V8i (Selectseries 5) Version 08.11.05.58 64 Bit
Project Notes: Analyzing Node DB-Detention Pond
Model A: Includes 8 detention systems to control runoff before it enters detention pond DB.
Model B:Includes 4 detention systems to control runoff before it enters detention pond DB.
Issue:
The flowrate into node DB does not change with additional detention storage under 10-Year Storm ModelThe flowrate out of node DB increases with additional detention storage (model A) under 10-Year Storm Model.
Additional notes:
Upstream detention nodes include orifice and weirs to control watershed runoff.
SewerGEMs - NEWR.zip
Hi Jesse,
Thank you so much for your assistance. This has helped me understand the model some more and the continuity error has dropped since adding pond outlet structure at POS-19 as you suggested.
Is there a way to model the overflow per factor 1? In other words, when the upstream detention structures fill up, does the overflow make its way to detention pond DB?
The goal of the the upstream structures is to control the downstream runoff and pond elevation, so I wanted to confirm if the overflow doesn't get get lost or neglected because the ponds fill up.
Thank you,
Suraj
Hi Suraj,
When a pond's water surface elevation reaches the top, overflow occurs which is lost to the system. It does not get routed anywhere and it accounted for in the "overflow volume" in the mass balance seen in the Calculation Summary window.
If you need to direct the overflow somewhere else, you will need to use a separate pond outlet node and direct the discharge using a conduit connected to an outfall, connected to the downstream element. See this article for more.
Regards,
Jesse DringoliTechnical Support Manager, OpenFlowsBentley Communities Site AdministratorBentley Systems, Inc.
Answer Verified By: Suraj Kumar
Sorry about the late response - I just wanted to confirm our model was set to go. Adding an orifice to the pond outlet structure and confirming the overflow has helped with the model's accuracy. Thanks so much for your help.
Hi Suraj, I'm glad to hear that. Happy to help.