How to Calculate the Freeboard of a Node in InfoSWMM/H2OMAP SWMM


Note:   How to Calculate the Freeboard of a Node in InfoSWMM/H2OMAP SWMM from the Model Results

The freeboard for a node in InfoSWMM/H2OMAP SWMM can be calculated with a 4 step process:

1.   Copy the Node Rim Elevations from the DB Tables for Junctions to Excel,
2.   Run the model and then copy the Maximum HGL from the Junction Summary output table to Excel,
3.   Calculate the Freeboard in Excel as the Rim Elevation minus the Maximum HGL in Excel,
4.   Create a new column called Freeboard in the Junction Information DB Table and paste the Freeboard from Excel.

You will be able to perform Map Displays or Map Queries now using the new Freeboard information column.
Figure 1.  4  Step Process to Calculate Freeboard

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