| name | cagis-conflate |
| description | Cross-reference OSM data against CAGIS quarterly road centerlines and ODOT TIMS Road Inventory for ground-truth validation of defect classifications. |
| when_to_use | User mentions CAGIS, ODOT, ground truth, cross-reference, validate classification, compare centerlines, or check highway type |
| allowed-tools | Read Grep Glob Bash(python *) Bash(curl *) |
| argument-hint | [zone or way-id] |
| arguments | ["target"] |
CAGIS Ground-Truth Conflation
Cross-reference OSM against authoritative sources for: $target
Authoritative datasets (from RESEARCH-FINDINGS.md)
CAGIS Open Data Hub
- URL:
data-cagisportal.opendata.arcgis.com
- Content: Quarterly-updated road centerlines + addresses for Hamilton County
- License: Public-domain-equivalent (City of Cincinnati). Requires disclaimer + credit in
source= changeset tag
- Accuracy: National Map Accuracy Standards for 1"=100' base map, NAD83
- Use for: Road geometry validation, address verification, new road detection
ODOT TIMS Road Inventory (NOT YET INTEGRATED)
- URL:
tims.dot.state.oh.us
- Content: State-certified mileage for HPMS reporting; annual update
- License: No copyright per ODOT GISP Ian Kidner
- Attributes: Lane miles, federal-aid eligibility, speed zones, NHS designation
- Use for (when wired): Highway classification ground truth (is this road state highway? federal-aid? what speed zone?)
- TMS tiles:
https://tiles.mblaine.com/ohio/{z}/{x}/{y}.png (mblaine's Mapnik render of ODOT data)
- Status: An independent API audit on 2026-05-08 could not locate a working
ArcGIS REST endpoint for TIMS at the documented
gis.dot.state.oh.us
paths. Until a working endpoint is wired in src/osm/, do NOT include
"ODOT TIMS" in the source= tag of any submitted changeset.
TIGER/Line 2024
- File:
tl_2024_39061_roads.zip (Census Bureau, FIPS 39061 = Hamilton County)
- Released: September 26, 2024; data through May 2024
- Use for: "What would TIGER look like today" reference — differences vs 2005-imported OSM are cleanup candidates
Conflation workflow
- Ingest — Download CAGIS road centerlines into PostGIS (or local GeoJSON)
- Buffer match — For each OSM way, find CAGIS centerlines within a buffer distance
- Hausdorff distance — Score geometric similarity between matched pairs
- Attribute compare — Check highway classification, name, oneway against CAGIS
- Flag mismatches — Ways where OSM says
highway=residential but CAGIS says connector/arterial
Key misclassification pattern
The 2007 TIGER import mapped CFCC A4x codes to highway=residential by default (RESEARCH-FINDINGS Item 3). Many should be:
highway=unclassified (rural connectors)highway=tertiary (suburban arterials)highway=service (driveways/alleys)
CAGIS and ODOT TIMS are the authoritative sources to determine the correct classification.
Source attribution
Every changeset that uses CAGIS data must include:
source=CAGIS Open Data Hub (data-cagisportal.opendata.arcgis.com)
with the required disclaimer and data creator credit per CAGIS terms.
