OpenStreetMap
Less roads == better data?
Posted by Dion Dock on 19 October 2012 in English. Last updated on 20 October 2012.I saw a presentation on OSM at SOTM.US. They measured the quality of OSM pre and post redaction by looking at the number of highway miles. It got me to wondering, can we get higher quality data by removing roads?
In the US, the “base map” was the now famous import of US census TIGER data. The Census bureau has mapped Forest Service logging roads and driveways, and they were imported as highway=residential. However, they quite often seem to be wrong. Consider some of the Oregon coast range, how much value a driveway adds or even where it belongs, and changing roads in the desert.
I suspect these roads were created then abandoned. The only way to know for sure is to go out there and survey them.
This got me to thinking that the map might actually be improved by removing ways. What do you think?
Discussion
Comment from Aury88 on 19 October 2012 at 07:15
You’re probably right, but I think is better a way with a wrong tag than a not reported way, also because redesigning a way and assign a correct tag is much harder, and takes more time, than simply change the tag.
Comment from Sundance on 19 October 2012 at 14:08
Of course if the roads don’t exist they should be removed, but if they do they should be tagged appropriately.
Forest Roads might be two possibilities; highway=unclassified or highway=track
Driveways highway=service, service=driveway (you might want to add access=private)
Comment from Mele Sax-Barnett on 19 October 2012 at 18:48
@Sundance: +1, this is the same strategy that I use when cleaning up tiger streets in a forested or rural area
Comment from nmixter on 19 October 2012 at 19:05
I would take TIGER any day over an empty map. Sure some of them may be tagged incorrectly, but it gives people an excuse to get out and check them. Many have already been fixed and checked. I would hate to have to survey all those roads by hand. The TIGER data should only be selectively deleted in rural areas or where it hasn’t been touched. And the new data needs to be carefully verified to make sure it connects with existing data.
Comment from z-dude on 19 October 2012 at 23:45
I’ve been adding a ton of minor roads and tracks to the west coast of Vancouver island, and I’ve been discovering road access to provincial parks which previously had not routing.
It was a couple years ago that a bus full of kids got stranded overnight on logging roads travelling from Bamfield to Victoria and got lost due to a wrong turn. If they had rural roads mapped out and on a gps, they wouldn’t have gotten lost.
Note: Google is now mapping these minor roads these days. (They didn’t a few years ago)
So.. I’d prefer it if these roads didn’t get deleted. I added a bunch of roads by my home town for hunting and fishing purposes. The overgrown logging roads may turn into path/generic when it is passable by foot or bike only.
Comment from z-dude on 19 October 2012 at 23:47
Another place to convert ‘highway=residential’ to track would be in the Desert areas so that tourists dont get routed on 4 wheel drive tracks.