[Talk-us] Counties Data Import

Ted Mielczarek ted.mielczarek at gmail.com
Wed May 14 15:28:12 BST 2008

Just had this pointed out in #osm:

What data source did you use for this? Was it from TIGER? The borders
don't seem to line up with the state borders (from TIGER) that we
imported previously. It looks a bit messy. :-/ I've also noticed that
the borough boundary I imported (also from TIGER) for my town doesn't
line up with the county borders at all:
 The borough border seems to match reality a little better (the river
is the county and borough boundary).


On Mon, May 12, 2008 at 7:27 PM, Ian Dees <ian.dees at gmail.com> wrote:
> I uploaded the data with the lines overlapping. I figured by combining the
> ways into one with left and right tags, we are making it quite a bit harder
> to query the database to determine which county any particular point is in.
> Also, there would be a significant amount of work to write the import app to
> do that, and I didn't think it was worth it to add time on both ends of the
> workflow.
> On Mon, May 12, 2008 at 6:14 PM, Ted Mielczarek <ted.mielczarek at gmail.com>
> wrote:
>> On Fri, May 9, 2008 at 10:41 AM, Ian Dees <ian.dees at gmail.com> wrote:
>> > Hi everyone,
>> >
>> > While I was trying to figure out how to divide the massive NHD dataset
>> > into
>> > more management pieces, I found a county boundary dataset and converted
>> > it
>> > to OSM.
>> >
>> > I uploaded Wisconsin and Minnesota county boundaries and submit them for
>> > your review. One minor issue:
>> >
>> > http://tah.openstreetmap.org/Browse/?x=1036&y=1489&z=12&layer=tile
>> > ... shows that each county is a separate, closed way in OSM. This means
>> > that
>> > at most boundaries, the dashed lines that are used to render political
>> > boundaries are overlapping and look odd. I can't see a way around this
>> > without losing metadata.
>> >
>> > If you have any opinion on how this data is represented, please let me
>> > know.
>> > Otherwise, I will upload the rest of the country later on this weekend.
>> I looked at this data when I uploaded the state borders a while ago.
>> The state borders I (and Adam) split by hand into non-overlapping
>> sections, tagging them with left:state and right:state appropriately.
>> I figured it would be too much work to do the county borders manually
>> like that, but I didn't feel like trying to write a program to do it
>> in an automated fashion either. I'm not really excited for having lots
>> of overlapping borders like that, but I guess I can manually clean up
>> the ones in my area if I care enough.
>> -Ted

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