When running a simulation in ICM, you’ll be required to enter simulation parameters. These values will have in impact on the level of detail of the predicted simulation and the time taken for the simulation to run.
Start and finish times: If you’re running time series rainfall events then these need to match that. Remembering to add some time on after the rainfall event finishes as flows continue through the system. If you’re using a design rainfall event then you can set the times blank, and leave a lag in the rainfall settings.
Timestep(s) : The interval in which the model runs.
Results Timestep Multiplier : This is the frequency with which a snap shot of the results is taken. A value of 1 takes a snap shot every 1 second. A value of 20 takes a snapshot every 20 seconds. If you put in a value of 0 you will not get any snap shots so will not be able to display any of the simulation. However, the maximum value is tracked for all timesteps and this is what is brought up when we use the max grind scenario.
Gauge Timestep Multiplier : This is the Results Timestep Multiplier for the selected items as represented in the run dialogue selection list so if it’s a smaller value than the results timestep multiplier it will provide more detailed results.
Set the value to 0 if you do not want additional time-varying results for your gauge points. A gauge timestep multiplier greater than the results timestep multiplier is pointless as you’d be just getting the same results calculated twice, but for the selected points, less frequently. It also might give you odd results in the content of your model so just don’t do it!