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As a low-cost countermeasure to rural intersection crashes, transverse rumble strips (TRS) provide an audible and tactile warning to drivers approaching an intersection with the primary goal of decreasing crashes that result from running a stop sign. The objective of this project is to evaluate the effectiveness of different TRS patterns on stopping behavior at rural stop-controlled intersections. Eight rural intersections in St. Louis County, Minnesota, were selected as test sites. Milled-in rumble strips were installed at the sites that varied in terms of number of panels (2 or 3) and number of rumble strips per panel (6 or 12). Speed, traffic volume, and video data were collected at each site before, 1 month after, and 9 months after TRS installation to evaluate various crash surrogate metrics. The most significant metrics affected by TRS configuration included percentage of vehicles engaging in a full/rolling stop at the intersection, change in average speeds on the approach near the intersection, percent of vehicles traveling 45 mph or more, and percent of vehicles engaging in late braking. A qualitative summary of the various metrics suggested that the 3-panel, 12-rumble strip design performed the best. Noise analyses were also conducted to assess whether the number of rumble strips per panel (6 or 12) affected exterior and in-vehicle noise. No significant differences in exterior noise were found, and both panels produced sufficient in-vehicle noise to alert a drowsy driver. As a result, noise was not a factor in selecting one panel type over another.

While pedestrian safety countermeasures contribute to reducing vehicle-pedestrian crashes, their impacts on winter maintenance operations are sometimes overlooked during design. There is a need to investigate the best practice guidance and solutions for the design, installation and maintenance of pedestrian safety features for year-round maintenance. To address this, we conducted a search of literature as well as agency interviews to identify and document current best practices for designing and implementing pedestrian safety countermeasures for year-round maintainability. The countermeasures reviewed included curb ramps, crosswalk markings, corner radii, curb extensions, refuge islands, and speed humps and raised crosswalks. The information collected allowed for the development of conclusions and recommendations for these features. The design dimensions and features of pedestrian curb ramps are established by the Americans with Disabilities Act and should have a slope of greater than 1:12 and a maximum cross slope of 1:50. Durable materials can be used for crosswalk markings, and these can be grooved into the pavement to provide protection from abrasion. Bulb-outs should use a 1:2 or 1:3 upstream taper and a 1:3 downstream taper. When used, tight radii of 15 feet or less should be employed. Refuge islands can range from 6 feet or greater in width, 24 feet to 40 feet in length, with a 4-foot or greater walkway width. Finally speed humps and tables should be between 3-4 inches in height, with lengths of 12-14 feet (humps concave in shape) and up to 22 feet (tables).

This toolbox was developed to provide a summary of information that local agencies should be aware of to prepare for connected and autonomous vehicles (CAVs). The main goal of this toolbox is to assist local agencies in preparing for CAVs in the short term--5 to 10 years. Since local agencies are not generally expected to have the resources to become test beds; this report provides information so that local agencies can leverage ongoing activities and resources to prepare for CAVs.

The installation and maintenance of pavement markings represents a significant financial investment for local agencies. Local agencies need a mechanism to better understand the value; cost; and need for markings along their roadways to make the best use of available budgets. This project developed a prioritization approach and spreadsheet tool (link provided in box 15) to assist local agencies in meeting this need. Multicriterion decision analysis using the simple additive weighting method was employed to assess the multiple factors/criteria that affect pavement marking decisions. An Excel spreadsheet tool was developed to implement this approach using different pavement marking alternatives; including centerlines; edgelines; centerlines and edgelines; high-visibility markings; and enhanced-durability markings. The criteria considered by the process include project type; County Roadway Safety Plan (CRSP) rating; functional classification; pavement condition; traffic volume; age of current markings; pavement width; preferences for marking costs; desired marking durability; and crash reduction potential. This tool is posted on the Local Road and Research Board (LRRB) website in the "Resources" section at the following URL: https://lrrb.org/resources/. Factor weights are used to assign a relative importance to each of these criteria for a respective alternative compared to other alternatives. The result is a performance rating score for each marking alternative relative to all model criteria and factors that provide users with information on the relative performance of different marking alternatives in comparison to one another and an estimated project cost for the highest ranking alternative for a site. The highest scoring alternative represents the marking that should be considered for use. Additionally; the tool ranks all sites being evaluated compared to one another based on the highest rating scores from each individual site.

The Pavement Marking Prioritization Tool provides a means for users to estimate the cost of pavement marking projects.