Texas Basemap - Transportation Map Data

This resource contains statewide networks of roadways, railroads, bridges, and low-water crossings, for Texas only.

Roadways detail: The Transportation Planning and Programming (TPP) Division of the Texas Department of Transportation (TxDOT) maintains a spatial dataset of roadway polylines for planning and asset inventory purposes, as well as for visualization and general mapping. M values are stored in the lines as DFOs (Distance From Origin), and provide the framework for managing roadway assets using linear referencing. This dataset covers the state of Texas and includes on-systems routes (those that TxDOT maintains), such as interstate highways, U.S. highways, state highways, and farm and ranch roads, as well as off-system routes, such as county roads and local streets. Date valid as of: 12/31/2014. Publish Date: 05/01/2015. Update Frequency: Quarterly.

Bridges detail: As with the roadways, both on-system and off-system bridges are maintained in separate datasets (54,844 total bridges, 36,007 on-system and 18,837 off-system). Bridges have numerous useful attributes, see coding guide [1] for documentation. One such attribute identifies structures that cross water: the second digit of Item 42 “Type of Service”. If the second digit is between 5 and 9 (inclusive) then the structure is over water. The bridges datasets are valid as of December 2016.

The roadways and bridges datasets contained here were obtained directly from TxDOT through personal correspondence. An additional transportation data resource is the Texas Natural Resources Information System (TNRIS) [3]. The railroads and low-water crossings were obtained through TNRIS.

November 2023 updates: in the years since this data archive was first published, TxDOT has developed an open data portal for downloading their roadway inventory and other datasets. Also, in 2023 TNRIS was renamed as the Texas Geographic Information Office (TxGIO). Their datahub [3] is continually evolving, but still has the tnris.org domain for now. We are not updating any of the basemap data in the contents list below, which was current at the time of Hurricane Harvey.

References
[1] TxDOT Bridges Coding Guide (download below)
[2] TxDOT Open Data Portal [https://gis-txdot.opendata.arcgis.com/]
[3] TNRIS/TxGIO data downloads [https://data.tnris.org/]