PL 59, Stable References for Evolving Roads: Match to 3200005710

Abstract PL 59, Stable References for Evolving Roads 7/1/2025 – 6/30/2026 KYTC has been purchasing HERE speed data from 2011 through 2023. This information has been very useful for road projects, as well as the SHIFT scoring process. From about 2016 to the present, the Kentucky Transportation Center has conflated the HERE road network to the current HIS network enabling each segment in the HERE network to be assigned a corresponding HIS route and milepoints. This process has been adequate to meet the needs of SHIFT and speed data requests. However, the HERE and HIS networks are not static. The geometry and underlying IDs of each network changes over time. The HIS milepoints of many route segments often change, even if the underlying geometry of these segments do not. To address these discrepancies, there is a need to establish a longitudinal linkage between the networks over time and to perform a more in-depth conflation of the HERE and HIS networks. The results will open up new opportunities to analyze the impact of roadway changes on speed in Kentucky as well as any other changes in speeds over the full extent of HERE data coverage (2011- 2023). Furthermore, other historical data such as safety performance and maintenance records that are linked to the historical versions of the HIS network can be accurately referenced in longitudinal studies.