[Lonnie A]

I agree with Cameron, it looks like the first surface was converted to integer which is why it is flattened between contours.

[Lonnie A]

Chris,
From the way I read of you method I don’t think you’d have to go the effort you did to get the information. In Mapper you can select a cell and have it plot the depth time series by right clicking on the location of interest with the depth layer turned on.

[Lonnie A]

Laura, If you look under GIS tools in the geometry editor there is a xs cut line table. The interpolated XS should have xy points in it. Not sure why your interpolated XS doesn’t have them. What version of RAS are you using?

Couple things to try is use the edit tools add/move/remove points and adjust a vertices or two. That should populate the table if it doesn’t have xy points. The other thing is how are you exporting to Arcmap? In version 4.0.1 under the main ras interface select gis tools to open mapper. Then under geometry right click XS and save layer to get a shape file. The process is similar in version 5.0.3 but called export feature.

If you are using the file/export gis data from the main window to export to arc map using georas I believe there is a check box in there to include interpolated cross sections.

[Lonnie A]

You can’t overlap the 2D and storage areas. You can use storage area connectors to connect the two.

[Lonnie A]

Looks like varied precipitation is not making it into v5.0.4. I suspect we’ll see v5.0.4 sometime late spring or summer 2018.

[Lonnie A]

You can’t just drag the ends of the cross-section, you need to resample them from the terrain file. It also looks like the xs aren’t geospatial but are just perpendicular to the channel centerline?
You sometimes have to close and reopen RAS to get the graphics to update.

[Lonnie A]

You need to extend the cross-sections out past the floodplain extents.

[Lonnie A]

Typical FEMA models will be to just add a flow change locations and not a junction as each reach is usually a separate model.

[Lonnie A]

A quick way to help guide proper XS layout is to put a simple 2D model together of the area if you have the topo that you can put into a terrain file for RAS. You can run the model and use the flow tracings as a guide. The other useful tool is to plot the WSE contours from the resulting 2D run and the XS should roughly parallel those. The 2D doesn’t have to be overly complicated and you can run artificial flow as you are only using it to see the conveyance pattern vs trying to compute a true WSE.

[Lonnie A]

A quick way to help guide proper XS layout is to put a simple 2D model together of the area if you have the topo that you can put into a terrain file for RAS. You can run the model and by reviewing the flow tracings as a guide. The other useful tool is to plot the WSE contours from the resulting 2D run and the XS should roughly parallel those.

[Lonnie A]

The next version of RAS (v5.0.4) I believe will have the capability of applying varied precipitation across a single mesh….I’m not certain losses make it into the next version yet though. If not you’ll just have to apply the excess precip value from HMS letting HMS take care of the soil losses.

[Lonnie A]

Try making the cells that connect to the culverts as large as possible. Your culverts look large so they can probably convey more volume in one time step than what the cell can provide at the initial time flow begins to reach the culverts. This causes continuity difficulties in converging to a solution. A “cheat” I sometimes have to do for cases like this is to alter the terrain at the head and tail water to create more volume in the cells. This is usually on the order of tenths of a acft or less so the artificial added volume doesn’t have a impact on the peak elevation but helps when you have flow just starting to enter the culvert. Another thing you might try is to set a higher n-value in the bottom say 6″ to foot of the culvert to reduce the initial capacity of the culverts.

[Lonnie A]

Its probably a problem with the conversion. If you open the interpolated xs editor and look under options you can edit (or add) vertical n values.

[Lonnie A]

Flow direction is positive if downstream direction has the cell face running left to right.

[Lonnie A]

If cell centers don’t have a inundation under them they don’t report the WSE. I think this is because when you show depth it’ll vary within the cell based on the underlying terrain and since only reporting one value it uses the depth under the cell center, which if no inundation exist there, nothing gets reported. The attached shows the limits of the connector and I put penciled in the elevation (using horizontal render) to show the elevation matches the hydrograph.

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