On Tuesday 03 July 2018, osm.tagg...@thorsten.engler.id.au wrote: > > A waterway=canal, waterway=river, or waterway=stream way inside a > lake or pond is probably appropriate to connect an in-flow to an > out-flow in a direct line, to allow software to easily trace > waterways through lakes or ponds (which are essentially just widening > of the waterway) without having to process areas. In this case the > waterway going through the larger body of water should share a node > with the outline of the lake at the in-flow and out-flow points where > they way and the outline intersect.
Connecting waterways through lakes based on flow has been a subject of dispute for a long time. It is highly unlikely that there will ever be full agreement on this and even less that this will manifest in mapping. It often boils down to questions like 'Does the Rhone flow through Lac Laman or does it enter into Lac Laman and exit again on the other side'. But all of this is something completely separate from the question how to map verifiable navigation routes within lakes. Note a very practical reason not to use the waterway key for mapping navigation routes within lakes is that mapping a navigation route that coincidences with a river/canal running through and being mapped through a lake is much simpler because you can just use an additional tag instead of a separate geometry. -- Christoph Hormann http://www.imagico.de/ _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging