SWMM5 Routing Time Step Summary

SWMM5 Routing Time Step Summary

This table is a summary of the iterations, times steps and amount of node and link bypasssing that occurs during a SWMM 5 simulation. It is listed in the text output file or the .rpt file of SWMM 5 which the file shown when you use the Report/Status command.


The minimum time step is the smallest time step used during the simulation.

The average time step is the mean time step used during the simulation.

The maximum time step is the maximum time used during the simulation.

The percent in steady state is the percent of the total simulation time spent in steady state during the simulation.

The average iterations per time step is the total number of iterations during the simulation divided by the total number of time steps or step count in this table. This will range between 2 and 4 iterations as SWMM 5.0.018 has a minimum of 2 and and a maximum of 4 iterations.

The Step count is the total number of time steps during the simulation.

The percent of bypassed links are the link flows that are NOT computed between time step iteration 2 and 4 because both the upstream and downstream node depths are converged in the current time step.

The percent of bypassed nodes are those nodes that have been converged between time step iteration 2 and 4. The node depth is still calculated, however, between iterations 2 and 4 as long as the whole time step is not considered converged.

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