Arterial Highway Capacity and Level of Service Analysis for Florida
Contracting Agency: Florida Department of Transportation Principal Investigator: Dr. Scott Washburn
Recently completed NCHRP Project 3-70 (Multimodal Level of Service Analysis for Urban Streets) resulted in the development of level of service (LOS) methodologies for the automobile, bicycle, pedestrian, and transit modes based on traveler perceptions.It was the intent of NCHRP that these methodologies be incorporated into the forthcoming Highway Capacity Manual (HCM) 2010.
As a leader in the implementation of Highway Capacity Manual (HCM) analysis methods, and with a particularly strong interest in the arterial multimodal analysis techniques, the Florida Department of Transportation (FDOT) sponsored a project, â��Multimodal Arterial LOS Modeling and Testingâ�� (BDK-75-977-13), in which the multimodal LOS models resulting from NCHRP Project 3-70 were tested in four Florida cities and the results evaluated by a panel of traffic engineers and planners.The intent of that project was to determine the applicability of these analysis techniques to Florida conditions and the feasibility of implementing these analysis techniques in the FDOT LOSPLAN software.The main recommendations resulting from that project were:
The current HCM 2000 method for determining automobile LOS (based on average travel speed by arterial class) should be retained in ARTPLAN and the forthcoming HCM 2010.
Since the bicycle and pedestrian facility models do not produce LOS rankings across the full range, consider a reevaluation of the models that could lead to the development of two or three facility models, being distinguished by roadway type (e.g., local, collector, arterial).
Given the previous recommendations, and to better coordinate the LOS classification schemes between modes, it was recommended that the automobile, bicycle, and pedestrian modes use the same number of LOS threshold value classifications, probably two or three classes.
FDOTâ��s project manager and the University of Florida Principal Investigator strongly supported those recommendations.
In July 2009, the national Transportation Research Boardâ��s Highway Capacity and Quality of Service Committee (HCQSC) met and decided what auto, bicycle, pedestrian and transit techniques for arterials would appear in the 2010 HCM. It decided not to include the proposed NCHRP 3-70 auto LOS methodology. Rather it decided to eliminate arterial classification altogether and use a new service measure (%FFS instead of absolute speed).Although some committee members felt that travelers may evaluate conditions differently for at least two arterial classifications (namely, high-speed/low-signal-density arterials versus low-speed/high-signal-density arterials), no documented research could be presented and, therefore, the decision to eliminate arterial class was made.
The proposed NCHRP Project 3-70 models for the bicycle, pedestrian, and transit models were accepted by the HCQSC without modification. The bicycle and pedestrian models were largely based on, and developed from, FDOTâ��s bicycle and pedestrian LOS models. Over the last eight years, two of the criticisms of FDOTâ��s bicycle and pedestrian models are they are not sensitive enough to different facility types (e.g., arterials vs. local streets) and the LOS does not change enough when bicycle and pedestrian improvements are made along state arterials.
The objectives of this project are to: 1) recommend the appropriate number of arterial classes and the corresponding LOS thresholds for the auto, bicycle and pedestrian modes; and 2) make the corresponding updates to FDOTâ��s ARTPLAN software.
Transportation Research Center Lily Elefteriadou, Ph.D., TRC Director
University of Florida Civil & Coastal Engineering
512 Weil Hall | PO Box 116500 | Gainesville, FL 32611-6580
352.392.9537, Ext. 1409