Flood Damages Reduced New Features

New 'Holdout Grid' Inundation Configuration 

A new Inundation Configuration (IC) was added that allows a user to compute flood damages reduced by reservoirs and levees using gridded hydraulic inputs. This new inundation configuration works similarly to the existing 'Holdouts' configuration, but uses geotiff grids produced in RAS Mapper instead of cross-section data as hydraulic input.

The Holdout Grids IC provides many advantages over the existing Holdout IC:

  • Can compute FDR with 2D HEC-RAS Models
  • Easier to setup and maintain as importing cross-sections and ensuring they stay consistent with the HEC-RAS model is no longer required
  • Cross-section vs. stream alignment stationing is no longer a concern for determining without levee stages.
  • Only structures in wet cells can be damaged, eliminating the sometimes unrealistic basement damages that can occur in cross-section computes. 

Defining Regulated and Unregulated Grid in new Holdout Grid Event.

Figure: Defining the Regulated and Unregulated Event Grid Inputs for a Holdout Grid Inundation Configuration


Estimating Damages Behind Levees with In-Channel WSELs

Figure: Structure in Leveed Areas Use Stream Centerline to Query Water Surface Elevations in Without Levee Compute 

Cross-Section Computes

Cross-Section Compute Data Checks

Better data checks for cross sections computes now notify users in the compute dialog where hydraulic inputs are not found.

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