[Imports] [Talk-us] MA towns

Richard Weait richard at weait.com
Thu Oct 20 13:50:19 UTC 2011


On Thu, Oct 20, 2011 at 9:10 AM, Metcalf, Calvin (DOT)
<calvin.metcalf at state.ma.us> wrote:
>  If nobody objects I'll start uploading the towns from the admin8 file and stow file

Dear Calvin,

I have an objection and a suggestion.  See below.

> I noticed that a couple of the counties are only relations (i.e. the ways aren't tagged admin_level=6) so no lines are going to go in there.

I'm not sure I understand what you say here.  Are you saying that some
admin areas are only tagged on the relations?  Are you also saying you
object to such tagging only on the relations?  Or are you saying that
you won't upload into areas that are tagged only on the relations?

> With this done all borders in Mass will be represented by a tagged way, if that looks good I can put in the new counties and state boarder files that don't include any overlaps.

I believe that this thread (perhaps the other threads on the same
topic) has established that MA borders are sub-optimal.  Those borders
are from various imported sources.  Those imported sources disagree
with each other as shown by crossings and parallel borders where they
should be a shared line.

My objection is this.  Importing state wide data from yet another
source without addressing the existing border weaknesses will make the
MA border condition worse, not better.

My suggestion is this.  Please consider _editing_, not _importing_,
these town boundaries in a way that greatly improves MA borders.  Work
in very small areas at one time and touch each way individually, by
hand.  Reconcile the new town borders with the existing county / state
borders and improve those as you go.  Use a single way where
inappropriate duplicates now exist, and add the way to each of the
appropriate border relations.

Starting with Stow, (is this the right Stow?)
http://www.openstreetmap.org/?lat=42.4237&lon=-71.5119&zoom=13&layers=M
you might decide that the existing town border is correct-enough, then
merge the Worcester / Middlesex border to the town line where they are
expected to overlap.  Refer to other sources, perhaps aerial imagery,
at the same time and you'll have the opportunity to fix other problems
in / around Stow as well.  Then do a couple of the adjacent towns as
well.  Adjacent towns should be easier because you'll have already
sorted out one of the shared borders.

Yes, this sounds like a lot of work.  Yes, this is slower than just
throwing the import data over the garden wall.  But.  Do this and show
us a before and after screenshot with the beautiful, improved MA
borders.  Do this and provide these lists with the details of your
workflow and any helpful tricks and troublesome traps.  Do this and
perhaps you'll have other MA mappers flocking to assist in the great
MA border cleanup.  You can make the MA borders and the cleanup
process an example for other areas sharing the same border
shortcomings.

Best regards,
Richard



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