Caltrans gives technical update on Equity Index; tool intended for project-level use

Caltrans staff presented a technical update on the agency's Equity Index (EQI) and described how the tool is being integrated into Caltrans planning and investment processes.

The presentation to the Data Implementation Subcommittee of the Equity Advisory Committee was led by Mason Noorani, data policy adviser in the Director's Office of Equity and Tribal Affairs, and Henry McKay, transportation analysis branch manager in the Director's Office of Sustainability. Caltrans launched EQI Version 1 in March 2024 and is now using it in several internal use cases.

Caltrans said the EQI is designed to be transportation-focused and spatially granular. Henry McKay described the team's two main design goals: "to have something that was really transportation focused" and to build spatial granularity using census blocks rather than larger tracts so the tool can highlight neighborhood-level conditions. The tool groups indicators into three categories: demographic screening (low-income and tribal lands), traffic exposure (proximity/volume and crash exposure), and access to destinations (mode-specific accessibility measures).

For income screening, the team said it uses a low-income definition aligned with California guidance (the presentation referenced the AB 1550 low-income definition). For traffic exposure, Caltrans uses federal HPMS traffic counts and weights truck traffic more heavily, applies a distance-decay weight (strongest within 50 m up to 500 m), and screens the top 20% (80th percentile) of impacted blocks. For crash exposure, the team relies on the Transportation Injury Mapping System (TIMS) data from UC Berkeley and excludes crashes on controlled-access facilities when assessing neighborhood-level crash exposure to better capture incidents that affect nearby residents.

On access to destinations, Caltrans calculates routed accessibility to jobs, stores, schools and hospitals by mode and then forms ratios (for example, transit access relative to auto access). Henry McKay explained the approach'"All the accessibility calculations do is just do those type of calculations but for every little area in the state"'and noted the team also models bicycle and pedestrian gaps such as the difference between technically rideable routes and those on low-stress networks that most people would use.

Caltrans emphasized the tool's use cases. Mason Noorani outlined current applications: integration of EQI metrics into the Caltrans System Investment Strategy (CSIS) metrics, inclusion in the Transportation Planning Scoping Information Sheet (TIPSIS) to surface equity needs during preplanning, use to define underserved communities for SB 960 outreach, and exploratory work with the Division of Safety to enhance methodologies. The agency also maintains a public EQI web map and an internal project-analysis tool that allows staff to draw a project footprint and estimate directional impacts based on project assumptions.

Committee members asked how the EQI handles gaps in observational data and whether community-sourced or "near-miss" datasets and climate-related safety factors could be incorporated. Subcommittee member Martha Armas Kelly urged the team to incorporate qualitative community reporting and climate-related risk factors such as localized flooding and lighting. McKay and Noorani acknowledged data gaps, said some near-miss and micro-level datasets are less transferable statewide, and said Caltrans plans to improve the tool iteratively and explore adding additional risk factors where consistent data are available.

Caltrans said the EQI currently screens about 45% of the state's population on the demographic criteria, with narrower results for combined transportation burden screens (traffic exposure covers ~18% of the state population; access-to-destination gaps cover ~42%; the combined transportation-based priority population screen covers ~16%). The team said an internal EQI user guide is under development and expected to be available to Caltrans staff by spring 2026.

Caltrans provided a contact inbox for feedback and said the EQI underlying datasets are already being used by some partners for localized analysis.

Looking ahead, Caltrans staff said they will continue refining indicators, pursue incorporation of additional safety- and climate-related inputs where data permit, and expand district-level support for project-level EQI analyses.