Kinematic wave: junction depth

[Pozzo]

It is my first time in the SWMM forum, so Hallo everybody.
I have a doubt about kinematic wave routing at nodes in SWMM 5. I believe that the model only applies flow continuity at junctions (outflow equals the sum of the inflows), so how can SWMM calculate flow depth at junction nodes?
Running some test models, I have confronted node depth with the depths of the downstream and upstream links joining at the node, but I did not find any logical unambiguous relation among them.
Does anybody know where I can find some technical references (i.e. description of the equations and the solution techniques adopted by the model ) about kinematic wave routing in SWMM 5?

Thank you for your help and time

Simone Pozzolini

[dickinsonre]

Hi,

The simple answer is that SWMM 5 applies the depths at the upstream and downstream ends of the links to the upstream and downstream nodes of the link. The depths in the link are found from the link area and the link area is found from the link geometry and the computed flow in the link at the end of the last time step.

The above description applies to non Storage and non Divider nodes in the KW solution. If the node is a Storage node or Divider node the node depths are computed directly from the geometry of the node and the outlet conduits of the node.

Best Regards,
Bob Dickinson
CDM Inc.