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QGIS SWMM Junctions Set Attributes: Difference between revisions

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<li>'''General Options:'''
:*'''; Maximum Depth Option (Ymax):'''
::* Set to 0.0:&nbsp; Initializes the Ymax for all junction nodes to 0.0. This option may be overwritten by the parameters set in the 'Nodes connected to 2D with inlets (underground pipe network)' section.
::* Leave as is:&nbsp; Leaves the Ymax value as is for all junction nodes. This option only applies if using 'Edit Feature In-Place'.
:*'''; Nodes receiving subcatchment flows option (if connected to 2D):'''
::* Based on options selected below:&nbsp; Parameters set in the following sections will be applied.
::* Set Apond = 0.0; Ysur = 0.0 (overwrites options below):&nbsp; Forces subcatchment outlets to use 0.0 for Ysur and Apond (turns off ponding). When ponding is off, node surcharging is reported as 'flooding' to SWMM and is immediately transferred to the 2D domain.
 
<li>'''Nodes connected to the 2D without inlets (through embankment culvert):'''
:* '''Ysur:'''&nbsp; Sets the surcharge at nodes connected to the 2D with inlets. Recommended value is 0.0.
:* '''Apond:'''&nbsp; Set to the approximate area of the 2D cells associated with the 1D/2D BC culvert connections layer(s). A larger area may improve stability, but may artificially attenuate discharges.
 
<li>'''Nodes connected to 2D with inlets (underground pipe network):'''
:*'''; Maximum depth (Ymax) option (overwrites general setting):'''
::* Set to inlet elevation - node elevation:&nbsp; Sets the Ymax value to the inlet elevation minus the node elevation.
::* Use global option:&nbsp; Sets the Ymax value based on the parameters set in the 'Global Options' section.
:* '''Ysur:'''&nbsp; Set to 0.0 if using ponding. Otherwise, set to higher than expected depths to prevent flooding.
:* '''Area of ponding:'''&nbsp; Set to the approximate area of the 2D cells associated with the Inlet Usage connections layer(s).
 
<li>'''Nodes without a 2D connection (underground pipe network):'''<br>
When a node is not connected to the 2D, flood losses will be lost from the model resulting in mass losses and inaccurate results. To prevent this, allow ponding (option 1) or make the surcharge depth high (option 2).
:*'''; Option 1:'''
::* Surcharge depth:&nbsp; Set to 0.0.
::* Area of ponding:&nbsp; Set to some positive value.
:*'''; Option 2:'''
::* Surcharge depth:&nbsp; Set to a value higher than expected node depths.
::* Area of ponding:&nbsp; Set to 0.0.
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