I’m in the process of formally deprecating the key busway=* thanks to the existence of better tags such as bus:lanes but I first need to find all the issues of this tag as well as how this tag came about to be.
I know the following ones:
Ambiguous lane count (I have seen roads where the lanes of busway=lane weren’t counted towards lanes, though according to bus lanes, they should count). Actually brought up.
Lack of position (is it a bus lane in the middle or at the edge of carriageway?)
I also know that it was used at a time when access restrictions were more primitive e.g. oneway:bus wasn’t in use (see busway=opposite_lane akin to cycleway=opposite) and bus:lanesfirst had to be properly defined but I also want some text sources and first hand experiences.
To bump it a little, I’ve been drafting a proposal to formally deprecate it and is nearly ready aside from requiring some tagging examples (even better would be some illustrations for the examples like on cycleway=opposite but the focus is on the main core).
Example 5 shows a worse problem in lanes:* from the possibility of using lanes:bus:backward=1 + lanes:taxi:backward=1 for lanes:backward=1 . I feel that simply the question of whether busway=lane is counted in lanes= needs to be decided. It can be preserved as a crude method when someone doesn’t want to do all the motor_vehicle:lanes= + bus:lanes= in different number of lanes= on each section. That would ease bus lanes on wider roads.
It could be applied non-physically separated center-running bus lanes Shouldn't we make rules that suit each country's road system?
Another application is determining the side of bus lanes. bus:lanes= would have to be parsed. With busway:*=lane , it’s straightforward.
In either case, you can instead start with deprecating busway=opposite_lane only. That’s as easy as cycleway=opposite_lane recently.
Thanks. I’ve never used busway=, only the lanes: scheme which I’ve found to be clear and well documented.
In example 5, shouldn’t it just be lanes:psv:backward=1 instead of lanes:bus:backward=1 and lanes:taxi:backward=1? It’s not clear to me how example 5 is different from examples 2-4, which do use lanes:psv.
Yes but that’s a well established tagging style which is mentioned both in the proposal and in Bus Lanes (to the point where I say it’s the main way of tagging bus lanes on OSM).