Model Inventory of Roadway Elements (MIRE) and MIRE Fundamental Data Elements (FDE)

Traffic safety data has three components: collisions, inventory of roadway elements and volumes. All three components of safety data enable data driven safety analysis.

MIRE, the Model Inventory of Roadway Elements, is a federally recommended listing of roadway inventory and traffic elements critical to safety management. MIRE is intended as a guideline to help transportation agencies improve their roadway and traffic data inventories.

As defined in 23 CFR § 924.3, “MIRE Fundamental Data Elements (MIRE FDE)” means the minimum subset of the roadway and traffic data elements from the FHWA's Model Inventory of Roadway Elements (MIRE) that are used to support a State's data-driven safety program. 23 CFR § 924.11 requires that States shall have access to a complete collection of the MIRE fundamental data elements on all public roads by September 30, 2026.

Caltrans is underway in developing a data warehouse for California’s public roadways and upgrading to a new Transportation System Network Replacement (TSNR) which will allow for geospatial capability to link all safety data (collision, roadway, and traffic volume).

California has one of the largest roadway networks in the U.S. with approximately 160,000 local road centerline miles and 15,000 State Highway System (SHS) centerline miles. The non-SHS is owned and maintained by more than 500 local and tribal entities, so data integration with all large and small agencies will be a challenge for California.

Please view the below links/documents to learn more about the MIRE FDE. More information will be posted here when available. 

UC Berkeley SafeTREC has been contracted to work with Caltrans, as well as tribal, regional and local agencies to develop a pilot plan for how these MIRE FDE will be collected, maintained, and shared. Below are some of the reports completed by UC Berkeley SafeTREC.

FHWA Resources