Research Request - Initial road segments (Census/Caltrans LRS)

[tiffanychu90]

Complete the below when receiving a research request, and continue to add to this issue as you receive additional details and produce deliverables. Be sure to also add the appropriate project-level label to this issue (eg gtfs-rt, DLA).

Research Question

Single sentence description: Cut Census roads into segments

• Epic - Daskify RT segment speeds #592

Detailed description: Explore how road segments will tie into routes, trips, shape_ids. Do we need an order of segments the way we have for route segments?

How will this research be used?

Stakeholders & End-Users

Metrics

• Include all primary and secondary roads, whether or not they intersect with GTFS shapes.
• Only include local roads that intersect with GTFS shapes.
• Buffer the original Census Bureau file first to find the intersection, then bring the original geometry back in.
• For GTFS shapes, start with stops with intersecting to local roads -> buffer around 50 feet. Filter out for linearids that are already found.
• Then move onto roads -> buffer.
• Cut all the secondary, primary, and intersecting local roads into segments.

Data sources

• Cal-ITP data sources:

• GTFS shapes.

• GTFS trips.

• External data sources:

• Census Tiger- all California roads are located in GCS bucket in the shared_data folder as "all_roads_2020_state06.parquet".

Deliverables:

• Script and parquet file.

Timeline of deliverables:

• ASAP.