User:Jcreer/SMS:GSSHA Coverages

The GSSHA model makes use of the simulation based modeling approach. This requires defining coverages in the Map module to build the components for use in the GSSHA simulation.

A GSSHA simulation makes use of the following coverage types:

• Boundary Conditions

Boundary Conditions Coverage

Arc Properties

• Channel – User defines the channel properties here.
  • Channel type – User chooses which channel type here.
    • Trapezoidal – Trapezoidal channels are used to define channel routing in GSSHA models. WMS automatically assigns a link number to trapezoidal channel arcs.
      • Manning's n (MANNINGS_N): – Manning's n roughness coefficient. Appears under both Channel options. Enter the Manning's N integer here.
      • Depth (m) (BANKFULL_DEPTH): – The maximum depth of the channel represented by the GSSHA feature arc in meters. Only available for feature arc types of "Trapezoidal".
      • Bottom width (m) (BOTTOM_WIDTH): – The width of the bottom of the channel in meters. Only available for feature arc types of "Trapezoidal".
      • Side slope (H:V) (SIDE_SLOPE): – The horizontal value to one unit of vertical rise. Only available for feature arc types of "Trapezoidal".
    • Cross-section – The profile of irregular cross sections are defined using XY coordinate pairs. GSSHA computes conveyance parameters including area, top width, and conveyance at incremental depths of flow up to the maximum depth specified in the Max conveyance depth column of the table.
      • Manning's n (MANNINGS_N): – Manning's n roughness coefficient. Appears under both Channel options. Enter the Manning's N integer here.
      • Cross section:
        • Edit XY Series – Selecting this bring up the XY Series Editor dialog.
  • Most downstream arc of stream network – Turning this on assigns one arc as the most downstream and directs all flow from other arcs towards the selected arc.
  • Output hydrograph at downstream end – Turning this on will allow creation of a hydrograph at the downstream end.
  • Specify point source at upstream end – Turning this on will specify one
• Overland Flow BC –
  • Overland Flow BC Type: – A drop-down list with the following options:
    • Constant slope –
      • Constant slope: – Enter integer here
    • Constant stage (water surface elevation) –
      • Constant stage (water surface elevation): – Enter integer here
    • Variable stage (water surface elevation) – Define a WSE curve
      • Variable stage (water surface elevation) – Click on Edit XY Series... to bring up the XY Series Editor dialog.
    • Variable flow (cms discharge) – Define a discharge curve
      • Variable flow (cms discharge): – Click on Edit XY Series... to bring up the XY Series Editor dialog.
    • Variable flow (cfs discharge) – Define a discharge curve
      • Variable flow (cfs discharge): – Click on Edit XY Series... to bring up the XY Series Editor dialog.

Point Properties

• Overland Flow BC –
  • Overland Flow BC Type: –
    • Constant slope –
      • Constant slope: – Enter integer here
    • Constant stage (water surface elevation) –
      • Constant stage (water surface elevation): – Enter integer here
    • Variable stage (water surface elevation) –
      • Variable stage (water surface elevation) – Click on Edit XY Series... to bring up the XY Series Editor dialog.
    • Variable flow (cms discharge) –
      • Variable flow (cms discharge): – Click on Edit XY Series... to bring up the XY Series Editor dialog.
    • Variable flow (cfs discharge) –
      • Variable flow (cfs discharge): – Click on Edit XY Series... to bring up the XY Series Editor dialog.