[Tagging] Modelling the relation between a waterstream and one of its resurgence

[Richard]

On Wed, Sep 09, 2015 at 05:25:52PM +0200, David Marchal wrote:
> > map the underground stream if possible.
> As I don't know where the intake from the first stream is, I think I can't map it this way. Besides, wouldn't that make the link exclusive, i.e. tell that the water only comes from one point and exits at another? If so, I can't either, as no-one can be sure of that in karstic systems: you can be sure that a ponor feeds a spring, but not that only this single ponor feeds only this particular spring, as there can be other ponors feeding this spring, and other springs fed by this ponor.

missing data should not prevent the mapping of known good data. If it has been established as 
the "main route" than it is fine to map that. We have rivers with side channels and branches
that aren't completely mapped either.

The missing data on the intake is a problem in this particular case though.

> The problem is that the resurgence is renowned as a separate river, even if the link with the losing stream is well known, and those rivers both has their waterway relation. How can I map the link without messing with the separate waterway relations ? 

Not much different from confluence points of large rivers?

Richard