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'Secondary' drainage links are optional. Secondary links are only required if you want to take advantage of the split flow functionality provided by MUSIC X, which is discussed next.
Split flows
MUSIC X incorporates a facility to allow outflow components from source and treatment nodes to be routed via different flow pathways. This allows, for example, the routing of surface flows and groundwater/infiltrated flows via different treatment pathways.
If you setup a MUSIC X project with just 'Primary' drainage links, MUSIC will automatically route all default outflow components to the next downstream node (as defined by the 'Primary' drainage link). If you wish to route any default or other non-default outflow components via an alternate pathway, it will be necessary to use 'Secondary' drainage links.
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- The arrangement of drainage links must not create any "closed drainage loops" (an error message will be displayed if this occurs).
- When Once you create a secondary drainage link, you can edit the link . The properties dialog should automatically appear allowing allow you to select which outflow component you would like to associate with that link (as shown below). More than one secondary outflow link can be added to each node (up to the limit mentioned above) and more than one outflow component can be assigned to each link, if desired. If you hold down the shift key while selecting the secondary link from the drop down box, you will be able to create multiple secondary links and the automated link property dialog "popup" will be suppressed.
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- You will not be able to switch off any of the default flow components from the primary drainage links (e.g., pipe flow, weir flow etc). This ensures that all default flow components are always routed downstream (so water does not disappear!). You will not be able switch on any of the non-default outflow components via the primary drainage links (e.g., infiltration, reuse, ET etc). These non-default flow components can only be added via the secondary drainage links.
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