How are the MIKE FLOOD river-urban coupling links dealt with in MIKE+?
When the river model is simulated within MIKE+ (i.e. MIKE+ is not coupled to a MIKE HYDRO River setup file), the river-urban couplings are replaced by more simple connections. It is not correct if you have specified the ‘coupling’ in the 1D-2D Couplings, since the river-urban interface is now described in MIKE+ using ordinary connections (as Rivers and Collection Systems modules are both 1D models set up within the same GUI).
There are particularly two types of river-urban connections:
1. If the urban node is an end node, then the node type must be set to ‘River junction’ at the Nodes editor and the location of the connection to the river is defined in this river junction.
2. In the other cases (i.e. when connecting the end of a river to another node than an end node), the connection is defined in the Rivers editor, just like when defining a connection to another river.
Therefore, if you have specified the river-urban links in the 1D-2D Couplings editor, you would have to delete these river-urban couplings, and then define the corresponding connections in the Nodes editor or in the Rivers editor. Then the river boundary condition could be set up as ’River water level’ type.
NOTE: During the import in v. 2022, this type of coupling was not converted to connections - and it was a missing functionality. This import feature has been added in Release 2023. Therefore, you can import the MIKE FLOOD model in v. 2023 and the river-urban connections should appear as expected.