Rain Barrel LID Drain Outflow in SWMM 5.0.021


Subject:  Rain Barrel LID Drain Outflow in SWMM 5.0.021

 The drain outflow in a Rain Barrel LID is defined by the user defined drain coefficient and drain exponent and the simulation storage depth  The storage outflow does not occur until it has been dry for at least the drain delay time in hours.
Figure 1.  Storage Outflow or Drain Outflow for a Rain Barrel LID

Figure 2. You can see the effect of the Drain Delay in the output file for LID Simulation.



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