In 2019, the Virginia Transportation Research Council (VTRC) published Improving the Identification and Characterization of Arterial Congestion Bottlenecks by Zhao and Venkatanarayana. The report described a study recommending that the Virginia Department of Transportation and the Office of Intermodal Planning and Investment pursue development of data conflation and bottleneck ranking tools and explore the implementation of the arterial bottleneck identification methods in rural areas and for before-after studies.
The current study was initiated in January 2019 to implement the two recommendations of the original study. The study consisted of two phases. In Phase 1, VTRC researchers adapted and applied the previously developed method to select intersections in the Culpeper District. Based on the promising results and validation feedback from field experts, Phase 2 was initiated to explore the possibility of developing a conflation tool and to adapt further and apply the bottleneck algorithm and visualizations to all signalized intersections in Virginia. Between February and July 2020, the VTRC research team collaborated with a research team from Old Dominion University to develop new methods and scripts to conflate statewide INRIX XD, annual average daily traffic, posted speed limit, and signalized intersection data wherever they were available. These conflation results were then used by the VTRC research team to analyze arterial bottlenecks across the state. Project stakeholders deemed the statewide bottleneck ranking and before-after study results to be reasonable and useful. The stakeholders are highly interested in further adapting and using the developed methods and scripts for project prioritization, for monitoring of the operational performance of intersections, and to make decisions in the field. The methods, results, and conclusions from these two implementation efforts (the Culpeper District and statewide) are documented in this report.
The full document is available online from VTRC at http://www.virginiadot.org/vtrc/main/online_reports/pdf/21-R9.pdf