Flow out of detention pond decreases with less storage

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 Model
The 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