Executive Summary

The Kentucky Transportation Cabinet (KYTC) has adopted a data-driven decision-making process to allocate funds for highway improvement projects. This process — Strategic Highway Investment Formula for Tomorrow (SHIFT) — requires that candidate projects be scored on five critical metrics: safety, asset management, congestion, economic growth, and benefit/cost analysis. The congestion metric is vehicle hours of delay (VHD), which was first developed for the SHIFT 2020 cycle (1). For SHIFT 2022, VHD is estimated using probe speed data acquired for 166,527 directional miles of Kentucky highways.

This report summarizes analyses performed using 2018-2019 HERE speed data, and their use in calculating congestion performance measures to support SHIFT 2022. After acquiring 2018-2019 probe speed data from HERE Technologies, Inc., we implemented a procedure developed as part of an earlier research effort to process data and link them with Kentucky’s highway inventory network. These data continue to provide good coverage of Kentucky’s roads, despite the data provider making some adjustments to its original data sources.

Probe speed data were used to calculate congestion performance measures, including VHD, for SHIFT 2022. For locations where such data were inadequate, HERS speed model was used to estimate hourly speeds (1).

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© 2021 University of Kentucky, Kentucky Transportation Center

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Center, the Kentucky Transportation Cabinet, the United States Department of Transportation, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names or trade names is for identification purposes and should not be considered an endorsement.