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About Your Neighborhood 3. Over the past two years, changes to my neighborhood as a place for. . .

The recently released Highway Safety Manual (HSM) published by AASHTO provides a comprehensive set of tools for evaluating and identifying opportunities to improve safety for highway facilities. Included in the HSM is a quantitative method for predicting crashes on the basis of recently developed scientific approaches. These predictive methods currently exist for three facility types: rural two-lane roads; rural multilane highways; and urban and suburban arterial highways. To enhance precision, each HSM predictive method should be calibrated for location conditions. This paper demonstrates the HSM calibration procedure for total crashes in Oregon. The research identified three critical data collection limitations on information about pedestrian volumes, minor road traffic volumes at rural locations, and minimum sample size for underrepresented crash locations. Most of the calibration factors for Oregon were determined to be considerably lower than the expected value of approximately 1, and this observation was attributed to Oregon crash reporting thresholds and procedures. The paper includes an evaluation of crash severity distribution methods and an assessment of the significance of collision type distributions on the overall predicted crashes.

This paper presents a before-after study of bike boxes at 10 signalized intersections in Portland, Oregon. The bike boxes, also known as advanced stop lines or advanced stop boxes, were installed to increase visibility of cyclists and reduce conflicts between motor vehicles and cyclists, particularly in potential "right-hook" situations. Before and after video were analyzed for seven intersections with green bike boxes, three intersections with uncolored bike boxes, and two control intersections. User perceptions were measured through surveys of cyclists passing through five of the bike box intersections and of motorists working downtown, where the boxes were concentrated. Both the observations and survey of motorists found a high rate of compliance and understanding of the markings. Overall, 73% of the stopping motor vehicles did not encroach at all into the bike box. Both motor vehicle and bicycle encroachment in the pedestrian crosswalk fell significantly at the bike box locations compared to the control intersections. The bike boxes had mixed effects on the motorists' encroachment in the bicycle lane. The number of observed conflicts at the bike box locations decreased, while the total number of cyclists and motor vehicles turning right increased. Negative-binomial models based upon the data predict fewer conflicts with the boxes, particularly as right-turning motor vehicle volumes increase. Observations of yielding behavior at two bike box and one control intersection found an improvement in motorists yielding to cyclists at the bike box locations. Differences in the traffic volumes and location contexts make firm conclusions about the effects of green coloring of the boxes difficult. Higher shares of surveyed motorists felt that the bike boxes made driving safer rather than more dangerous, even when the sample was narrowed to respondents who were not also cyclists. Over three-quarters of the surveyed cyclists thought that the boxes made the intersection safer.

Buffered and protected bike lanes are increasingly recognized as a valuable tool in enticing potential or wary cyclists to use a bicycle for transportation. These facilities—which provide extra space and (in the case of protected bike lanes) physical separation from motor vehicles—have been studied and are preferred by many bicyclists over traditional bike lanes. There has been little research, however, on the difference between buffer types and how they affect people's sense of the safety and comfort of bicycling. This paper uses data from surveys collected for a multicity study of newly constructed protected bike lanes to examine the influence of various hypothetical and actual buffered bike lane designs (both with and without physical protection) from the perspective of current bicyclists ( n = 1,111) and of residents living near the new facilities ( n = 2,283) who could be potential bicyclists. Findings suggest that striped or painted buffers offer some level of increased comfort, whereas buffers with some sort of physical protection, even protection as minimal as a plastic flexpost, yield significant increases in perceived comfort for potential cyclists with safety concerns (the interested but concerned). Of residents living near recently built protected bike lanes, 71% of all residents and 88% of the interested but concerned indicated that they would be more likely to ride a bicycle if motor vehicles and bicycles were physically separated by a barrier.

This report presents a before-after study of bike boxes at 10 signalized intersections in Portland, Oregon. The bike boxes, also known as advanced stop lines or advanced stop boxes, were installed to increase visibility of cyclists and reduce conflicts between motor vehicle and cyclists, particularly in potential-right-hook‖ situations. Before and after video were analyzed for seven intersections with green bike boxes, three intersections with uncolored bike boxes, and two control intersections. User perceptions were measured through surveys of cyclists passing through five of the bike box intersections and of motorists working downtown, where the boxes were concentrated. Both the observations and survey of motorists found a high rate of compliance and understanding of the markings. Overall, 73% of the stopping motor vehicles did not encroach at all into the bike box. Both motor vehicle and bicycle encroachment in the pedestrian crosswalk fell significantly at the bike box locations compared to the control intersections. The bike boxes had mixed effects on the motorists' encroachment in the bicycle lane. The number of observed conflicts at the bike box locations decreased, while the total number of cyclists and motor vehicles turning right increased. Negative-binomial models based upon the data predict fewer conflicts with the boxes, particularly as right-turning motor vehicle volumes increase. Observations of yielding behavior at two bike box and one control intersection found an improvement in motorists yielding to cyclists at the bike box locations. Differences in the traffic volumes and location contexts make firm conclusions about the effects of green coloring of the boxes difficult. Higher shares of surveyed motorists felt that the bike boxes made driving safer rather than more dangerous, even when the sample was narrowed to respondents who were not also cyclists. Over three-quarters of the surveyed cyclists thought that the boxes made the intersection safer.

Sponsoring Agency Code Supplementary Notes AbstractThis report reviews the existing state of the art and also the state of the practice of freight performance measurement. Most performance measures at the state level have aimed at evaluating highway or transit infrastructure performance with an emphasis on passenger transportation. Freight performance measurement ultimately requires evaluation of performance of the entire freight transportation system, which includes highways, waterways, rail, air, and modal connections. This requires considerable expansion of thinking beyond the traditional focus of state Departments of Transportation (DOTs) on highway performance. This project builds upon past and current work in the area of freight performance measurement and incorporates recent literature on the development of these measures. A thorough review of state practices is conducted by surveying state DOT web sites and reporting on the measures most frequently recommended and used by individual states for planning purposes. The emphasis is on the application of performance measures to freight transportation, and the usefulness and limitations of these measures, is discussed.Recommendations are made for potential freight performance measures for each freight mode (air, rail, trucking, and water/marine), including initial information on data availability, validity, and feasibility given existing data for Oregon.Future research needs discussed include additional data collection and development required to support performance measures, what is needed to track system performance changes over time, and testing of measures for their sensitivity and usefulness for policy and decision-making.

Bicycling as a mode of transportation is increasingly seen as a healthy alternative to motorized transportation modes. However, in congested urban areas, the health benefits of bicycling can be diminished by the negative health effects associated with inhalation of particulate matter. Particles of small size (ultrafine particles <0.1 μm) are the most harmful, even during short-duration exposure. Because vehicular exhaust is the major source of ultrafine particles, the impact of traffic levels and bicycle lane characteristics on exposure of bicyclists was studied. Ultrafine particle exposure concentrations were compared in two settings: (a) a traditional bicycle lane adjacent to the vehicular traffic lanes and (b) a cycle track design with a parking lane separating bicyclists from vehicular traffic lanes. Traffic measurements were made alongside air quality measurements. The cycle track design mitigated ultrafine particle exposure concentrations for cyclists. Results showed statistically significant differences in terms of exposure levels for the two bike facilities, as well as correlations between traffic levels and exposure level differences. Results also suggested that ultrafine particle levels and spatial distribution were sensitive to proximity to signalized intersections. Findings of this research indicated that, in high traffic areas, bicycle facility design had the potential to lower air pollution exposure levels of bicyclists.