Import/Maine Admin Boundary Import

From OpenStreetMap Wiki
Jump to navigation Jump to search


Maine Admin Boundary Import is an import of Maine municipal boundaries.

Goals

Update OSM municipal boundaries in Maine. Before starting, most boundaries were missing and many more had incorrect geometry.

Status

The initial import effort has completed.

Reviewed has been completed.

Import Data

Background

Data source site: https://maine.hub.arcgis.com/datasets/6811dd5d3c6c402c9e852ea9c633fb75
Data license: https://www.arcgis.com/sharing/rest/content/items/6811dd5d3c6c402c9e852ea9c633fb75/info/metadata/metadata.xml?format=default&output=html
Type of license: "Access: Public Use: User assumes risk"
ODbL Compliance verified: yes

Import Type

A one-time import done manually.

Data Preparation

Data Reduction & Simplification

The data fields are simple. Most effort is focused on geometry.

Tagging Plans

  • name= [as provided by the data source]
  • boundary=administrative
  • admin_level= [will follow United States admin level for Maine]
  • Add the existing GNIS "populated place" nodes as role:label for town relations
    • remove gnis:*=* tags, except re-key gnis:id=* to gnis:feature_id=*
    • remove is_in=* and import_uuid=* tags
    • fix place=village to place=town or place=city
    • Not making any changes to population tags

Changeset Tags

The changeset description will be descriptive.

Source="maine.gov in consultation with Maine community on #local-maine on Slack US"

Cleanup work is done with tag documentation=<link to this wiki page> and source=MEDOT

Data Transformation

Using JOSM to compare subject and reference geometries. Manually merging the data.

Data Merge Workflow

Team Approach

ZeLonewolf plans to do all the work, with blackboxlogic working as QA and source of local knowledge.

Workflow

Detail the steps you'll take during the actual import.

Information to include:

  • Work one municipality at a time.
  • Visually compare subject to reference.
  • Adjust the subject to match the reference.
  • Commits will be limited to a single municipality, or a small group of nearby boundaries.

Conflation

Manual (JOSM)

Review

Blackboxlogic is did QA by reviewing all changesets and plans to do cleanup as needed.

Cleanup includes:

  • Associating gnis nodes with boundary relations as role:label
    • Create new gnis nodes where they don't exist already for cities/towns
    • Cleaning gnis node tags (place, etc)
  • Reviewing geometry
  • Fixing broken relations
  • Fix name errors
  • Fix place=city vs place=town (https://en.wikipedia.org/wiki/List_of_cities_in_Maine)
  • Remove names from boundary ways

See also

Discussed: https://lists.openstreetmap.org/pipermail/talk-us-maine/2021-January/000022.html

And more in the #local-maine channel of OSM US slack.

Concerns

"Townships" in Maine require some research to find the appropriate admin_level, and may need some re-tagging after the import.

Results

  • All county/city/town/township/gore (etc) are represented by administrative boundaries with correct geometry and tags
  • All city/towns have a role:label that has the correct place tag and correct gnis:feature_id tag
  • All city/towns have admin_level 8, everything else has admin_level 9
  • The role:label of any non-city/town has a place=village (but many non-city/towns don't have a role:label)
  • Townships that have a name have alt_name with their "T2 R3 Wels" style name
  • Tribal land was NOT included in this work and is still lacking in maine
  • Population tags were NOT improved with this work
  • Wikipedia and Wikidata tags were NOT completed with this work