Connect Wastewater Network Elements
This represents a guide on how to connect wastewater network elements in TWW.
General
TWW has a tool to connect wastewater network elements
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How to connect reaches to nodes or reaches to reaches
It does not matter, which layer is selected
The vw_tww_reach layer has to be in edit mode
Click the Connect wastewater network elements button
If you move the mouse over a reach, that can be connected, it is marked (orange color): you can click
Move the mouse to the network element, to which the first object will be connected (again: selectable objects get marked) and click again
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Note
the topology-layers are turned on in the screenshot to show the effect of the connection.
A window appears, where you can choose, which connection will be defined. If you connect a reach, the window looks like this:
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Note
there is no options ‘Reach Point From’ in this example, because in a connection from reach to reach, it is not allowed to connect a From-reach point to another reach.
If everything is ok, you will see a message in a blue bar on top of the map-window
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To show the new connection, save your edits, click on the TWW-SQL-Button (refresh network topology) and refresh the screen. Now you can see the new connection in the topology-layers
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Video Tutorial (not adapted for TWW)
How to delete a connection
There is no special tool in the moment to delete a connection between network elements.
Select the vw_tww_reach layer and set it to edit mode
Click on the Identify Features button and select the reach to modify by double clicking
Delete the value in the rp_…_fk_wastewater_networkelement field to delete the connection
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Note
Be aware of the ‘VSA Erfassungsgrundsätze’: A reach point from (rp_from_fk_wastewater_networkelement) should never be connected to another reach.
For example, when you have a reach discharging directly into another one without a structure between the two, the upstream reach should be connected to the downstream reach (rp_from_fk_wastewater_networkelement = downstream reach). But inversely, the downstream reach shouldn’t be connected to the upstream one. This rule is for swwf-channels (secondary network). In pwwf-network, there must be always a node between two reaches.