Different Values in Std Table 1 than in Stage and Flow Hydrograph

[NY-Hydro]

A student of mine brought to my attention that when conducting an unsteady RAS model of a Sunny Day run of river dam failure, the Standard Table 1 returns a different Q (Q Total) than is displayed in the Stage and Flow Hydrographs plot window under Maximum Flow.

I was at loss to explain why the Table is reporting a value larger than any value in the Stage and Flow Hydrograph plot or table. (6000 cfs in the table and 2100 in the Stage and Flow Hydrograph plot and table.)

Does anyone have any input?

[Anonymous]

The likely explanation is that the tables get their maximum values by sampling the computations at different time intervals. The hydrograph output table is based on values taken on the “Hydrograph Output interval” which is selected in the unsteady flow manager. The other maximum is taken from the results at every computational time step. Usually the hydrograph output interval is larger than the computational time step, so the maxima can differ.

[Author]

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