WMS:Storage Capacity Data

From XMS Wiki
Jump to navigationJump to search
HY8 Modeling Wizard showing the Storage Capacity Data step.

The Storage Capacity Data step is used to define storage capacity data and to route the hydrograph at the outlet through the culvert.


This step in the wizard lists all the crossings in the HY-8 coverage and allows defining storage capacity data for each of the crossings. The elevation-volume curve is defined from the DEM and the outlet/watershed boundary or the flood inundation polygon associated with the crossing. The elevations are defined from the headwater elevations in the HY-8 analysis. Alternatively, geometry of the area can be defined and the elevation-volume curve can be computed from this geometry or an elevation-area curve can be defined and the volume can be computed from this curve (a fourth option is that the storage can be entered directly into the storage capacity data dialog). When clicking on the Define button from the wizard, the Storage Capacity Input dialog appears, shown below:

Storage Capacity dialog.

In this dialog, select the option to use the DEM (this is the default if a DEM exists) to compute the volumes at each water surface elevation. Alternatively, enter the geometry of the basin upstream of the culvert or an elevation-area curve. If the Known Area option is selected, manually enter the area at each of the headwater elevations computed by HY-8.

After exiting the define storage dialog, the Detention Basin Analysis dialog shows the elevation-storage-discharge chart in an FHWA Hydraulic Toolbox dialog and allows viewing and editing the routed hydrograph and its associated data:

Detention Basin Analysis dialog.