I work for the Yukon Government Transportation Branch as a GIS Program Manager. We use Geotab in our fleet vehicles to track vehicle speeds. From my understanding Geotab consumes OSM data to pull speed limits. Since there are no speed limit tags currently applied to the highways it is running on defaults based on highway types. This is causing mis-reporting of speeding in some areas.
To remedy this, we initially hoped to simple pull the OSM road data, apply the speed limits, and reupload (mechanical edit). However, after contacting the Data Working Group were informed of the issues associated with this. Also pointed out were concerns regarding licencing and accuracy.
Initial Edits:
I had personally done a couple minor edits in the past but to better familiarize myself with OSM editing I started looking into updating just the speed limits in Whitehorse.
According to this page: Default speed limits - OpenStreetMap Wiki it looks like the default for the Yukon is 50 km/h so I didnât tag any street where that is true. I used the cities traffic By-law to identify streets where the speed limits is not 50 and then verified with streetview that traffic signs stated as such. (Streetview was recently recaptured for most of the city in Sept. â22, I disregarded any older imagery). If I couldnât verify with street view or actually seeing the sign while out and about I made no edit.
Is this approach appropriate in terms of licencing (by-law data) and accuracy (sign location verification)?
If there is no problems with the approach taken so far I would like to move onto the highwyas.
Next Steps:
Back to the initial problem. The information I have to update the Highway speed limits is:
Internal government data showing what the speed limits should be
Speed sign locations collected by the inspection crews collected in May â21
Streetview Data for some highways collected in September â22
Would a similar approach as that taken to update Whitehorse work here? I use the internal data as a jumping off point. I verify initially with the sign inspections that a sign does exists and with the correct speed posted. When available, I compare against streetview.
Are there any concerns with this approach? Especially with the use of sign inspections when recent streetview is unavailable?
According to this page: Default speed limits - OpenStreetMap Wiki it looks like the default for the Yukon is 50 km/h so I didnât tag any street where that is true.
for speed limits we usually tag every highway with the maxspeed because otherwise you donât know whether the information is incomplete or the default was intended and the limit omitted on purpose.
When you write âstreetviewâ, is this imagery for which you own the rights or is it google streetview or similar?
Donât do this
Creating data from Street View images, such as digitizing or tracing information from the imagery
âŚ
These restrictions apply to all academic, nonprofit, and commercial projects.
Thanks for the reply. So for all of the streets that I disregarded because the limit is 50 km/h, they should actually be tagged as such?
yes, at least this is what we do around here.
Yes I mean google streetview.
Unfortunately googleâs streetview is not a permitted source for osm because googleâs terms of service do not allow to derive data and use it as we do. (Donât know if your organization has a different contract with google so it might be ok).
I was unaware of the restrictions of googleâs streetview. Thanks for pointing them out. Without using that as a source, are the street sign locations collected by the government field crews sufficient in establishing speed limits? There sign locations were collected on the ground using GPS.
What would âexplicit permissionâ look like in this instance? Does it require a formal data sharing agreement? Like I said I work for the government and am being requested to update this data. Is that sufficient permission?
Without using that as a source, are the street sign locations collected by the government field crews sufficient in establishing speed limits? There sign locations were collected on the ground using GPS.
it depends. If the data is available with a suitable license, the question is about quality. For instance if a sign location was collected some years ago, things might have changed. Or if a gps position is a bit off, you might not get the correct road or direction (if you also have the information about road and direction for the photos, this is not an issue).
All inspections are linked to their associated road and attribution includes the direction. Dates vary highway to highway but the inspections are within 1-2 field seasons.
I believe this is sufficient in terms of licensing (assuming you can contribute the data according to the generic contributor terms). If you work for a third party, the organized editing guidelines are also relevant: https://osmfoundation.org/wiki/Organised_Editing_Guidelines
You should create a page in the wiki for the activity and link it from here in a new row you add (you need to create an account in the wiki to edit the wiki):