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HydroNodeCategoryValue code list


When implementing, we found a problem with the code values and definitions of the following code list:

In our datasets, we have nodes expressing where two or more links connect and there is not a value available for these as the the definition of a Junction is: "Node where three or more links connect."

Without in-depth hydrological expertise, we would suggest to amend the definition of Junction to "Node where two or more links connect."

If that isn't feasible, next alternative, would be to include a new separate code value for nodes where two links connect. What do you say?


  • Keiran MILLARD

    By Keiran MILLARD

    Hi Lena,

    Maybe this is a simplistic answer, but if there are only two nodes is it not a junction?  To be a junction there MUST be three or more nodes? 


  • Lena Hallin-Pihlatie

    By Lena Hallin-Pihlatie

    Hi Keiran,

    Yes, I agree. It's not a junction, but what is it then :-)

    Our pragmatic solution is to only give code list values to the nodes of category "source" and "outlet" and use the NilReason "unpopulated" for the rest of the nodes, as we cannot find a suitable value for them in the HydroNodeCategoryValue code list and we don't have information which of the nodes, which fills the critera (three or more nodes) of a "junction" in our database . Perhaps this is also the intention.

    Best regards,




  • Michael LUTZ

    The issue is solved in the FormOfRoadNode code list, which includes the values (among others):

    So maybe, we should just add the value pseudo node to the HydroNodeCategoryValue code list.

    Best regards,

  • Peter PARSLOW

    I like that idea - it's what we've (sneakily) done in some of our water networks, before someone pointed out that HydroNodeCategoryValue wasn't extensible.

  • Ilkka RINNE

    +1 for the new pseudoNode code list value.

    Any idea how & when this change could be done? Can we already use this for new datasets or is it better to stick with 

    <hy-n:hydroNodeCategory xsi:nil="true" nilReason=""/>

    for now?

  • Michael LUTZ

    Good question. Unfortunately, this would require a change in the IR. If we agree that this is the best way forward, we could formulate a change proposal and submit it to the 2016.4 sub-group for discussion and then the MIG for agreement. But it would still have to be processed with the other proposed corrigenda to the IRs, and that will take time.

    We should probably discuss how to already include values agreed by the MIG (e.g. as proposals) in the INSPIRE registry, so that they can already be used. This is a topic for the about-to-be-formed Registry control body, I guess.