Difference between “depth max extent (max)” and “depth (max)”

[Anonymous]

I am having trouble understanding the exact difference between “depth max extent (max)” and “depth (max)”. When looking at the two flood maps in Ras mapper, the inundated surface shown with “depth max extent (max)” appears to be much bigger, except that where it does not ovelapp the inundated surface shown with “depth (max)” a depth of 0 m can be observed.
Does it mean that when the calculated depth is too small, hecras is defaulting to a value of 0? What is the most accurate way to represent the maximum inudated area?

Thank you in advance,
Best regards,

[Anonymous]

Remember max extents is similar the Max Profile for a 1D model, in that the results are not representative of one time step. Max shows all cells max wsel or depth even though they may have occurred at different times. What i like to do is if my focus is on a certain portion of the inundated area, i put a dummy weir across the river and once the model is finished running, i plot the stage and hydrograph and it shows when the max HW and TW occurs. Then i go to ras mapper and and map the time to that time step. to me that is my max extents at my area of interest; then you can also show particle tracing and vector arrows

[Anonymous]

Thank you for your response.

You are right to point out that the max shows all the cells that are inundated at one stage but not necessarly at the same time.
However, this is not our problem. We would like to represent the maximum extent but we can not figure out the difference between “depth max extent (max)” and “depth (max)”. Both are supposed to show the all the area that is inudated at a certain stage. But, the area shown by “depth max extent” is much bigger,…
Where the two surfaces (“depth max extent (max)” and “depth (max)”) overlapp, the depth is the same, but where only “depth max extent (max)” shows an inudated area, the depth is equal to 0. Where does the difference come from?

Thank you in advance,

[cameron]

depth max extent causes any cell that gets wet to appear as fully wet. All dry parts of the cell get the threshold depth that you specified when you created the depth max extent.

[Anonymous]

I am facing the same problem.
From what I understand, “depth max extent” shows all cells that are wet, even though not completely. However, when the depth shown by HECRAS is equal to 0, does it mean that the average water level in the cell is below the average cell elevation?
If that is the case, then why can’t we see any water surface elevation for these cells?
Is there something that I miss?

There is nothing in the user manual about the actual difference between “max depth” and “max depth extent”,…

[Author]

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