TUFLOW SWMM Tutorial M02 Check QGIS development

SWMM Check Files

Text Data

When TUFLOW runs SWMM, it can accommodate for multiple INP input files within the SWMM Control file. TUFLOW combines the input INP files into a single combined INP file for the simulation execution. The combined file TUFLOW uses is written to the TUFLOW\results folder.

1. Navigate to the TUFLOW\results folder and open TS02_5m_001_swmm.inp in Notepad++.
2. Manual Data Review (Optional): Review the Junction, Outfall, Conduit, Losses, and XSections information in the text file.

QGIS Data

It can be useful to review the inp file created by TUFLOW after all inp files are combined.

1. Navigate to the TUFLOW\results folder and drag and drop TS02_5m_001_swmm.inp into QGIS.
2. This will open the 'GeoPackage - Create from SWMM inp ' processing tool.

   • SWMM Input File (inp): Prepopulated with TS02_5m_001_swmm.inp.
   • CRS for GeoPackage: Click the drop down menu and select ‘Project CRS: EPSG:32760 - WGS 84 / UTM zone 60S’.
   • SWMM Tags to ignore: leave blank.
   • GeoPackage output filename: Click the ... and select 'Save to File'. Navigate to the TUFLOW\check folder and set the GeoPackage output filename to TS02_5m_001_swmm_check.gpkg.

3. Click 'Run'.
4. Once the tool has finished, click 'Close'.
5. When prompted by QGIS, under 'Options', tick on 'Add layers to group', then select 'Add Layers' to open all layers within TS02_5m_001_swmm_check.gpkg. By default, all items in the available list should have been selected.
   
   

   
   

6. Manual Data Review (Optional): Review the Link--Conduits, Nodes--Junctions and Node--Outfalls information to verify the data matches the input values. This data represents the 1D pipe network details.
   
   

   
   

7. Since the layers in TS02_5m_001_swmm_check.gpkg have been compared with the input layers, the input layers can be removed from the QGIS workspace.

TUFLOW Check Files

Open the TUFLOW check files:

1. In Windows File Explorer, navigate to the TUFLOW\check folder and drag and drop TS02_5m_001_Check.gpkg and TS02_5m_001_DEM_Z.tif (hold Ctrl to select multiple) into QGIS.
2. When prompted by QGIS, under 'Options', tick on 'Add layers to group', then select TS02_5m_001_1d_to_2d_check_R and TS02_5m_001_swmm_pit_P (hold Ctrl to select multiple). Click 'Add Layers'.
3. Use the 'Apply TUFLOW Styles to Open Layers'.
4. Style TS02_5m_001_DEM_Z.tif (the topography check file) using the same hillshade styling as DEM_Hillshade:

   • In the QGIS Layers Panel, right click DEM_Hillshade and select Styles > Copy Style.
   • Right Click TS02_5m_001_DEM_Z.tif and select Styles > Paste Style.

5. In the QGIS Layers Panel, move the TS02_5m_001_DEM_Z.tif layer below the other check files so that the other datasets are visible.
   
   

   
   

Manual Data Review (Optional): Compare the 2D check files information against the the 1D check files to verify the model design is as intended.

1. How does the the pipe network invert elevations (Nodes--Junctions) compare to the the pit inlet (surface) elevations?
   

Proper Inlet 1D/2D Connections

Currently, the inlets are all specified to use cell each inlet is in for the connection to the 2D domain. This is often sufficient, but care needs to be taken especially with on-grade inlets. On-grade inlets divert a portion of the flow going past based on a few parameters such as approach flow (discharge going down the side of the roadway), velocity, and the inlet characteristics. To get an accurate approach flow, the connected cells must extend across the area conveying flow. Most urban areas have crowned roads so the connected cells should extend to the center of the roadway. The geometry in this example model is simplified with flow generally only on one side of the street.

To check that on-grade inlets have a sufficient number of connected 2D cells:

1. Move the SWMM_iu_TS02_001 to the top of the layer list so it will show up in front of other features.
2. Right-click on this layer and select Properties or use the symbology panel to use Categorized symbols based on the Placement field. Click the Classify button to force each category to a different color. This should show three ON_GRADE inlets with the rest being ON_SAG.
3. Right-click on the Nodes--Junctions layer in the sw02_001 folder and select Show Labels. This should indicate that the three on-grade inlets are Pit7, Pit9, and Pit15.
4. Turn on the TS02_5m_001_1d_to_2d_check_R layer and style as desired. Turn off the other check file layers to prevent clutter.
5. Compare the width of the 1D/2D connection cells with the roadway widths in the DEM (turn on if not already). It should be clear that the cells cover less than half of the roadways and may not represent the full flow-width that we are interested in.

There are two approaches to connect an inlet to multiple cells:

1. Within the inlet usage layer, the number of connected cells is determined by the Conn_width field. Increasing the connection width will select multiple cells. Note that a negative value will specify an exact number of cells regardless of the cell size. The default approach for selecting additional cells depends on whether the inlet is on-grade or on-sag. The details of the algorithm can be found in the TUFLOW manual.
2. Manually specify the cells to connect using an SX connection (polyline or polygon) and CN line to the inlet location. Note this method requires removing the Conn1D_2D attribute from the inlet usage layer.

For this model, increasing the number of cells will be used for Pit9 while manual connections will be created for Pit7 and Pit15. Note: When using the automatic method, the actual 1D/2D connected cells should be verified.

Make the following changes to the inlet usage layer:

1. Make the swmm_ui_TS02_001 layer editable by making it active (left-click) and clicking the 'Toggle Editing' symbol .
2. Right-click and select Open Attribute Table.
3. Clear the Conn1D_2D attributes for the rows representing Pit7 and Pit15. Selecting the nodes in the map will identify the appropriate rows.
4. Specify a value of -2 for the Conn_width for the row associated with Pit9. This will connect the inlet to exactly two cells regardless of the cell size.
5. Stop editing the layer and save the edits.

Next, the manual connections for pits 7 and 15 must be added. To save time, a 2d_bc layer with these connections has been provided.

1. Right click anywhere in the QGIS Toolbar Panel and tick on 'Browser Panel' from the 'Panels' options.
2. Within the QGIS Browser Panel, there is a dropdown directory, 'Project Home'. This directory is a shortcut to the location where the QGIS workspace is saved. In this case, it is a shortcut to the TUFLOW_SWMM_Module_02 folder.
3. In the 'Project Home' directory, navigate to the TUFLOW_SWMM_Module_02\Tutorial_Data folder.
4. Drag the 2d_bc_SWMM_Inlet_Connections_001_L layers from the Urban_Development.gpkg and drop it into the TS02_001.gpkg contained within the TUFLOW_SWMM_Module_02\TUFLOW\model\gis folder.

Add the line below into the TS02_001.tbc file in the TUFLOW\model folder.

• Read GIS BC == 2d_bc_SWMM_Inlet_Connections_001_L ! Reference the TUFLOW BC File
  

Rerun the model and review the check files to verify that the on-grade inlets are now connected to multiple cells.

TUFLOW Pipe Integrity Tool

Some of the optional manual data review exercises suggested in the previous sections can be easily carried out using the QGIS TUFLOW Plugin 'Pipe Integrity Toolkit', specifically the visual profile plot tools.

1. Open the '1D Integrity Tool' from the TUFLOW Plugin toolbar.
   
   
   
   
2. The resulting dialog will appear.
   
   
   
   
3. Set up the tool for this model:

   • Input Network Lines: Use the dropdown box and select TS02_5m_001_swmm_check >> Links--Conduits. Click the '+' button to add the layer as an input to the tool.
   • Input Network Points: Using the same process as above, add TS02_5m_001_swmm_check >> Nodes--Junctions and TS02_5m_001_swmm_check >> Nodes--Outfalls to the tool.
   • Input Tables: Leave blank as it is not used for SWMM data review.
   • Input DEM: Tick on and use the dropdown box to select TS02_5m_001_DEM_Z.

Note: For further information on the 1D Integrity Tool and its functionality, see 1D Integrity Tool.

The following example demonstrates the 'Flow Trace' tool. It will be used to create a profile plot for visual review of the 1D pipe network data input.

1. In the QGIS Layers Panel, right click Links--Conduits and select 'Zoom to Layer(s)'.
2. Use the 'Select Features' tool to select conduit 'Pipe6'.
3. At the bottom of the 1D Integrity tool dialog, there is a list of tools. Select the 'Flow Trace' tab.
4. Enter the following options:
   
   
   
   
5. Click 'Run'.
6. The tool will select all the upstream conduits and also add another output layer identifying the locations which fail the flow area and invert checks.
7. A Flow Trace window will appear. It provides a 'long plot' of the long sections of the various upstream paths from the selected conduit, highlighting the areas of continuity failures. The plot should be consistent with the output GIS layer that is also generated by the flow trace tool.
   
   

   
   

Up
Back to TUFLOW SWMM Tutorial 2