RDII Intial Abstraction in SWMM 5

Subject:  RDII Initial Abstraction in SWMM 5

RDII Initial Abstraction in SWMM 5

by dickinsonre
Subject:  RDII Initial Abstraction in SWMM 5 
The initial abstraction in each of the three components of RDII in SWMM 5 are updated at each time step.  The initialabstraction (ia) is:
 ia = iaMax - iaUsed 
based on the maximum amount of ia, the ia used (iaUsed), the recovery rate (iaRecov) and the month and class of RDII.  You can enter a value for iaMax, iaInit and iaRecov for each month. 
 
The iaUsed at the beginning of the simulation is set equal to iaInit

and if there is no rainfall



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