[Talk-us] Proposed (partial) import: New York State minor civil divisions.

[Brian M. Sperlongano]

As a data consumer of boundaries, this is sorely needed, and thanks and
sympathies for taking it on.  Will this clear up the mess of improperly
tagged CDPs from the original import as well as all of the admin_level=8
boundaries (many of which are mis-tagged CDPs)?  Long Island seems to have
the worst of it, and everything is glued to streets, making them
exceptionally prone to breakage.

On Wed, Dec 15, 2021 at 1:33 AM Kevin Kenny <kevin.b.kenny at gmail.com> wrote:

>
> The OSM representation of minor civil divisions in New York State has
> several problems.
>
> (1) About a third of the cities, towns and villages, most of them in the
> northern and western parts of the state, are missing entirely - apparently
> the TIGER and USGS imports never succeeded in importing them.
>
> (2) Many administrative boundaries in TIGER were simply incorrect. The
> state's database appears to be more trustworthy; for example, there was
> reasonable alignment between the state's data and the county's tax rolls in
> the case described in
> https://www.openstreetmap.org/user/ke9tv/diary/391486.
>
> (3) Few, if any, of the minor civil subdivisions' populations have been
> updated as of the 2020 census.
>
> (4) Some boundaries were conflated with watercourses that have changed
> course abruptly in Hurricanes Irene (2011), Lee (2011) and Sandy (2012).
> Because these changes were avulsion (abrupt change resulting from a
> specific catastrophe) rather than accretion (gradual deposition of
> sediment), erosion, or reliction (exposure of land by declining water
> level), they often did not move the boundaries, even though the
> watercourses have since been edited. These moved watercourses must be
> deconflated with the boundaries, and the boundaries returned to their
> proper places.
>
> New York State maintains authoritative data sets for minor civil divisions
> at http://gis.ny.gov/civil-boundaries/.  The license for these data is
> the state's standard open data license, available from
> https://data.ny.gov/dataset/OPEN-NY-Terms-Of-Use/77gx-ii52. This license
> governs several New York data products that have already been imported;
> most notably the Department of Environmental Conservation lands and
> campgrounds, the state parks and state historic sites, and the statewide
> address point data.
>
> Starting from the shapefiles available from gis.ny.gov, I've succeeded in
> making a topologically-correct OSM data set. It's available for inspection
> at
> https://kbk.is-a-geek.net/attachments/20211215/topo_cities_towns.osm.pbf
>
> The tag, 'user:ke9tv:fid' present on the ways is there because the
> conflation process that I'm using needs to know, for the ways that are
> already done, what the unique ID of the way was in the source database.  It
> will be removed from OSM at the conclusion of the import. The other odd
> tags are
>
> gnis:feature_id - Same meaning as in TIGER: the GNIS ID of the feature in
> question; a foreign key into many government databases.
> nist:fips_code - The FIPS code of the feature in question; another
> important foreign key that ties together government databases.
> us:ny:swis - The code for the feature in New York's Statewide Information
> System, again a foreign key into many external databases.
>
>
> The idea with this file is that I'll go through it, town by town. (There
> are 1600 towns; I should be able to stitch things together in a few weeks.)
> The workflow will be to copy-and-paste the relations for the municipalities
> into JOSM one at a time, do manual conflation of the borders, do manual
> conflation of the relations, update populations, add Wikipedia and Wikidata
> tags, and upload. I've only done one township - Champlain, New York - so
> far, as a test case.  It can be seen at
> https://www.openstreetmap.org/relation/13552232 .  Note that the two
> member ways https://www.openstreetmap.org/way/1012328548 and
> https://www.openstreetmap.org/way/1012328549 are already split, to allow
> seamlessly anchoring the boundary between Chazy and Mooers, the next
> bordering towns.  The villages of Champlain and Rouses Point are also done.
> The latter shares boundaries with the township, the county, the state and
> the United States.
>
> If there are any serious problems with this project, I'm prepared to
> revert or amend the two changesets that have been committed so far.
>
> Given the amount of manual work that's being done here, this hardly
> qualifies as a 'mechanical edit' - but given that the external data source
> is a specific file that we haven't used before, I thought it wise to run
> this by the community.  Please let me know of any objections!
> --
> 73 de ke9tv/2, Kevin
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