[Geo_Wick]

What a great document! Thank you Cameron, that answers all my questions and more.

[Geo_Wick]

Ah, that makes sense. The total volume released is appropriate (manually integrated, I don’t have access to the model files, only selected results).

Excellent suggestion to modify the hydrograph to see if the downstream areas are affected, I am keeping that one in my back pocket!! In this case, the downstream area is mainly a channel in a deep canyon. Usually I see maximum depths at the peak of the hydrograph for that type of terrain, so I’m not too concerned about depth increasing after the peak flow has passed.

In general, would you say that if “minor” oscillations occur after the peak flow, one can reasonably assume the peak flow is “accurate”? i.e., if I took the time to fully stabilize and resolve the oscillations, do you think I would be likely to see the same or very similar peak flow in the modified model?

[Geo_Wick]

Thank you for the explanations, cameron and jarvus, this makes a lot more sense now!

[Geo_Wick]

Thanks for the reference, Cameron, I somehow missed that section in the manual. However, the dam I am modeling is only 9ft high and unlikely to cause freefall, so it sounds like the shallow water equations may still apply. I will be sure to compare my results with the weir option results.

[Geo_Wick]

Thanks Jarvis. I have been using an initial elevation for the 2D reservoir area, and breaching at a set time. If I use an initial elevation with only one 2D area, wouldn’t it also fill the downstream area to this value?

I guess I could input an artificial inflow hydrograph upstream of the reservoir and instead of breaching at set time, breach at a set elevation…Do you know of any better way to do this?

[Geo_Wick]

Use the “Wet Cells” option, Maximum, and set threshold depth. Another option is to save your Depth Max as a raster based on terrain, and use GIS to show only depths >0.5ft. You may be able to do this directly in RASMapper using categories in display options. I don’t see “Depth Max Extent” option in 5.0.7.

I have also experienced the lack of recomputing problem. Try deleting the layer in RASMapper AND the created maps out of the folder the original version was saved to, that may allow you to recompute.

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