For probably around a year myself and coworkers have been unable to generate floodplain inundation polygons in ArcGIS using the HEC-GeoRAS tools. We can complete the layer set up, convert SDF files to XML files, import HEC-RAS results, and generate the water surface TIN. However, we are not able to do the next step, "Floodplain Delineation Using Rasters", instead an error will occur, saying "Failed to Obtain Terrain Layer, exiting".
We have two ideas about why this is happening.
1 - The file sizes of the DEMs we are using for the Terrain Layer are so large that the program is struggling to "obtain" the data and creating the error. The DEMs we have been using range from hundreds of megabyes up to tens of gigabytes.
2 - Our company transitioned our servers to the Cloud last year, which is making it difficult for GeoRAS to retrieve that data to perform the analysis (may be related to file size as well?).
Just wondering if anyone else has encountered this type of error and if there are any solutions. I haven't seen anything online about this. I developed a work around in GIS (basically doing what I imagine GeoRAS does behind the scenes), but the method didn't work great for a recent multi-river multi-reservoir model (it works better for linear systems). Thanks.