Traffic volumes and congestion across Utah have continued to increase in recent years, particularly on arterial streets. This increased traffic volume has amplified the emphasis on implementing access management techniques (i.e., raised medians or driveway consolidation) to alleviate some of the safety concerns associated with access on arterial streets. To determine the safety benefits provided by access management techniques in Utah, an evaluation of the safety performance of arterials in which access management techniques have been implemented within the state was performed. To complete the evaluation, a unique, yet proven, tool available through the Utah Department of Transportation was used. This tool is a geographic information system–enabled, web-delivered data almanac that allows researchers to establish specific filters that can be used to sort crash data, identifying high crash locations and establishing crash trends. Several locations where access management techniques have been implemented in Utah were selected for the safety analysis. Although crash rates were not reduced in every case as a result of the access management techniques, other safety improvements were observed. For example, the access management techniques generally reduced the more serious collision types; this resulted in a decrease in the crash severity. Because the overall severity of crashes decreased, the overall economic cost of crashes was reduced. The cost of installing the access management techniques was more than offset by this reduction in the cost of crashes.

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The intersections of major arterials are designed to facilitate the conflicting movements of numerous vehicles in a manner that is both safe and efficient. Accesses located within the functional area of major arterial intersections complicate intersection activity because additional conflicts arise from ingressing and egressing movements at the accesses. This research analyzed the impact of accesses on crashes within the functional area of major arterials. The effects of access spacing within functional areas and access setback from intersections were addressed. The functional areas of 144 signalized major arterial intersections across the state of Utah were examined. A database was developed and contained the frequency, type, and severity of functional area crashes as well as the intersection and roadway characteristics within the functional area. Statistical analyses were conducted to determine the influence of accesses on crashes within the functional area of intersections. The statistical analyses showed that the existence of accesses within the functional area was correlated with increased crashes and crash severity costs. In particular, an increase in commercial access density was associated with increases in crash totals, crash rates, and rear-end crashes in intersection functional areas. The analyses also showed that study intersections meeting Utah Department of Transportation corner clearance standards exhibited fewer right-angle crashes and lower crash severity costs. Adherence to such standards improves safety and increases efficiency of the transportation network and thus aids jurisdictions throughout the nation in making the most of the existing infrastructure.

Traffic volumes and congestion continue to increase on arterial roads. Safety and performance on those roads are continual concerns. Transportation systems must be evaluated on an ongoing basis to ensure that people and goods can be moved as efficiently and safely as possible. Safety and performance indices provide a method to numerically measure given data about a system so that comparisons and rankings on safety and performance can be made as objectively as possible. One of the sets of tools that have proved successful in improving the safety and efficiency of arterial roads are access management techniques. To determine which roads can most benefit from access management techniques, a prioritization process was developed to guide decision makers in the implementation process. Recommendations were given in the form of a decision tree classifying existing or future road segments into subcategories based on volume, signal spacing, adjacent land use, and other criteria. The objective of this paper is to document the steps followed to develop a performance index-based prioritization process to target arterial roads that would benefit from the implementation of access management techniques. Using the results of the research, decision makers can better determine which sections of roadway may benefit from controlling driveway access, installing raised medians, providing future planning, or looking to a solution other than access management.