If you’re a hydraulic modeler or civil engineer, you know the power duo: HEC-RAS for 1D/2D river modeling and ArcGIS for spatial pre/post-processing. The traditional bridge between them, , has a dirty little secret—it officially stopped updating around ArcGIS 10.2/10.3.

: HEC-RAS cannot process cross-sections that cross each other. Use the ArcMap editor to physically separate or bend the cut lines using vertices.