Hi @scarapella, I just noticed the use of this little waterway=link way via the new map produced that shows the end-points of flows in waterways:
https://waterwaymap.org/ends/#map=18.2/46.763195/-69.305047

I've not seen the waterway=lnk tag used before, but if that is important to map I'd suggest flipping the direction of https://www.openstreetmap.org/way/1236467015 so that it goes into the Allagash River instead of diverting the Allagash river's flow out.

See also: 
* https://github.com/amandasaurus/waterwaymap.org
* https://lists.openstreetmap.org/pipermail/talk/2024-January/088486.html