[Talk-ca] Out of date or incomplete NRCan-CanVec-7.0 data

James Ewen ve6srv at gmail.com
Sun Mar 3 23:52:16 UTC 2013

On Sat, Mar 2, 2013 at 6:38 PM, Tony Toews <tony at tonytoews.com> wrote:

> I'm just a casual editor who cleans up things I know first hand in a few
> small towns and a small city.    So I went to Landmark, Manitoba and saw an
> interesting, irregularly shaped out-of-date/incomplete polygon that was
> added.  I don't recall seeing it when I last visited there several months
> ago but who knows.
> Residential Area - Source - NRCan-CanVec-7.0
> This appears to display a shaded area on the user viewable map.

Follow the links to dig deeper into the information available.


> The problem is that this is very much out of date or incomplete.
> Furthermore, for that village/hamlet it's mostly nonsense.   Main street,
> which is the highway running north/south through Landmark is the
> commercial/industrial road through town although there are houses
> interspersed among the retail and commercial buildings and feed mill.
> Furthermore the residential area goes 1.5 blocks west and a few blocks east.
> So it might as well not even exist.

Or you could update it to reflect reality. It is difficult to ensure
that every landuse is perfectly represented, but it can be done. In
Sherwood Park the residential areas are mapped out, but sometimes the
corner store is sitting in a residential landuse, rather than being in
a commercial landuse area. Should we delete all landuse polygons
because some aren't perfect?

> Now judging on my memories of that village/hamlet it is probably at least
> ten years out of date.

Fix it today and tomorrow it will only be one day out of date. Ten
years from now someone else will be able to complain about it being 10
years out of date! :)

>  Does it serve any useful purpose?

Define "useful purpose". When you zoom out and look at Winnipeg, do
the various coloured areas provide you with any information?

>  Is it safe to delete that polygon or
> will it come back on some re-import in the future.

Would it be better to remove all the inaccurate information from OSM,
or to correct/update the inaccurate information?

If you look at the history, the polygon was imported by sammuell from
CanVec in an effort to correct data provided by vreimer. vreimer was a
very prolific OSM user that touched a great deal of the OSM database.
Much of the information provided by vreimer was looked upon by locals
as being of dubious quality. All attempts to contact vreimer failed,
and when a block was put on the account, vreimer disappeared. During
the licence change, we lost a lot of valid data that vreimer had
touched, and we are still working to replace much of that data to this

So, delete the information, and someone else *may* come by and replace
what you deleted. Update the information, and make a note in the
database as to what you did and why, and others can benefit from your

Deletion should be reserved for removal of obviously false
information. Out of date, or incorrect information should be updated
or corrected.

We've had some people "create" towns in the middle of nowhere, and
those change sets have been reverted, and removed from the database.
Buildings, roads, or other features that have been demolished, or
otherwise removed from reality obviously should be removed from the
database, but something like the out of date residential area in
Landmark Manitoba should be updated, not removed.


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