Tasmanian transport network, web-ready (LIST transport segments)

A single statewide copy of the LIST transport segments for Tasmania, prepared for use directly in web browsers. It is derived from the mirror at https://source.coop/mdsumner/thelist-opendata.

Data: (c) State of Tasmania, Creative Commons Attribution 3.0 Australia. Code that built this: https://github.com/hypertidy/thelist-opendata (MIT, R/10_transport_web.R).

Attribution

"LIST Transport Segments" from theLIST © State of Tasmania

Land Tasmania does not endorse this product or any use of it.

What is here

<snapshot> is the date of the newest source zip (the LIST release the layer reflects). Snapshot folders are never overwritten; a new LIST release gets a new folder and latest.json moves. Groupings or other records keyed on TRANSEG_ID should store the snapshot they were made against.

Columns

How it was made

• Read from the mirror's per-LGA GeoParquet (GDA94 / MGA zone 55).
• LIST clips a segment that crosses an LGA boundary into each LGA's file, each piece keeping the same TRANSEG_ID. The pieces are rejoined with a directed line merge (exactly shared cut vertex; no vertex moves, nothing reversed). For the 2025-07-10 snapshot: 1320 segments rejoined from 2646 pieces.
• node0 / node1 come from exact coordinate identity of segment endpoints in the source coordinates (wkpool merge_coincident, tolerance 0), so connectivity is integer equality. LIST_TRANSPORT_NODES carries no link to segments, so its TRANODE_ID is not used. Node ids are stable only within a snapshot. For multi-part segments, node0 is the start of the first part and node1 the end of the last.
• Reprojected with PROJ: inverse MGA55 to GDA94 geographic, labelled WGS 84 (the EPSG:1150 null shift, about 1 m).
• Rows Hilbert-sorted (gdal vector sort), ZSTD, 65536-row groups.

Known quirks (2025-07-10)

• 54 segments are still multi-part, 39 of them rejoined pieces that do not meet exactly.
• 839 of 284,831 segments differ from COMP_LEN by more than 1% in geometry length; not investigated.
• Whether LIST keeps TRANSEG_ID stable across releases is not yet known; it can be checked when the next release arrives.

Reading it

DuckDB:

GDAL:

ogrinfo -so /vsicurl/https://data.source.coop/mdsumner/tas-transport-web/2025-07-10/list_transport_segments.parquet