[Talk-us] Admin borders in the US: misalignments

Sun Nov 3 15:46:16 UTC 2013

Misaligned borders - we have a lot of these

early border imports came from multiple sources, and when they were
done, it was rare to look at other border imports in the vicinity and
clean things up. a good example is along the Hudson River, where
the county borders were from USGS (which were not very good borders)
and the places (cities, villages, CDPs) were from 2008 TIGER (better but
not great). while the ways for the places were often shared properly
by relations, the county borders were ignored because they didn't match
and the result was that the border lines down the Hudson were an
ugly mess.

in updating borders down the Hudson, i've found that frequently 2013
TIGER borders are different (and largely improved) over 2008, and there
is no reason to retain the USGS borders. likewise, i've similarly been
replacing the USGS state borders with TIGER 2013 as needed. if anyone
is foolish enough to take on these tasks, be aware of these things. in
densely populated areas in particularly (Rockland County NY was bad
and Westchester County may be worse) you may find a domino situation
where you need to deal with a bunch of old, outdated place borders.

Finally, one of the most festive situations i encountered was along
the Delaware River - the NY/PA border. one early mapper used
what looks like an NHD centerline for the border, which isn't
necessarily a wrong decision, except it matched up with neither USGS
county borders or any TIGER borders. for the sake of sanity this is
now entirely TIGER 2013. again, don't do borders unless you are prepared
to deal with the entirety of the situation that's in front of you.