Transportation Network Core Data Product¶
The Transportation Network CDP manages road network data (from OpenStreetMap) and transit data (from GTFS feeds). It produces routers, street exports, and transit metadata used by the Places pipeline.
Published Components¶
Nationwide¶
| Component | Description |
|---|---|
router_osm |
Base nationwide OSM file |
street_export_table |
GraphHopper-generated street export in BigQuery, derived from processed OSM |
validity_start_date |
Starting date of GTFS validity week for the season |
Regional¶
| Component | Description |
|---|---|
router_gtfs |
Regional GTFS file for building routers |
gtfs_link_mapping |
Mapping of transit routes to network link IDs |
router_disk_snapshot |
GCE snapshot with pre-built GraphHopper network data |
graphhopper_network |
Pre-built GraphHopper network files in GCS |
transit_stops |
BQ table of transit stop metadata from GTFS |
transit_lines |
GeoJSON of transit line metadata from GTFS |
street_cutout |
Regional cutout of nationwide street export |
routable_cells |
BQ table of H3 cells accessible by transit |
osm_cutout |
Regional OSM cutout used to build routers |
validated_gtfs |
GTFS file passed through the validator |
Data Configs¶
Located in transportation_network/configs/:
- usa/base.yaml — shared router settings, prototype for all regional configs
- {region}/{season}.yaml — season-specific settings (OSM version, validity date)
- {region}/ingestion/{season}.yaml — raw data ingestion (OSM and GTFS)
Nationwide sources live in USA-level configs; megaregion-level sources (like GTFS) live in per-region configs.
Key Concepts¶
Links¶
A link is a road segment in the network, identified by OSM way ID. Links have:
- Functional road class (FRC)
- Geometry (LINESTRING)
- State, timezone
- Composite segment ID (compseg_id) for segments that span multiple links
GTFS Validity¶
Transit routing uses a specific "validity week" per season. The Thursday and Saturday of this week are used for weekday/weekend transit routing during Places runs.