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This article summarizes key findings from National Cooperative Highway Research Program (NCHRP) Project 17-97, “Strategies to Improve Pedestrian Safety at Night” and the Safe Speeds and Safe Roadways pillars of the NCHRP Research Report 1157: Strategies to Improve Pedestrian Safety at Night guidance.

This Minnesota Department of Transportation report examines how local agencies balance safety, liability, and maintenance budgets when applying pavement markings to medium and low volume roadways.

This report provides a first look at 2025 pedestrian fatality data. Preliminary data have been adjusted slightly to account for historical underreporting. GHSA projects 6,732 pedestrians were killed in traffic crashes in 2025, a 7% decrease from 2024 and the third consecutive year with a decline.

The report also analyzes 2024 pedestrian fatality data from the National Highway Traffic Safety Administration’s (NHTSA) Fatality Analysis Reporting System (FARS). These are the most recent federal motor vehicle fatality data available and include specific information on crash characteristics – speeding, hit-andruns, alcohol impairment, time of day, roadway factors and vehicle types – that is not available in the 2025 state reported fatality numbers.

These analyses help explain when, where and why pedestrians are killed on U.S. roads, which can inform what countermeasures to use to help prevent future deaths. For example, in 2024, the percentage of both drivers and fatally injured pedestrians reported as distracted has increased significantly. This suggests additional efforts are needed to ensure people on the road are aware of their surroundings and take action to protect themselves and others.

Anthropogenic noise and light have been shown to impact wildlife behavior, distribution, movement, and population fitness
and survival. Traffic noise and light can inhibit wildlife use of areas adjacent to roads, impair wildlife perception of traffic
risks, and cause a barrier effect to wildlife occurrence and movement well beyond road edges. A critical action being taken
by states to repair wildlife movement across roadways is construction of wildlife crossings, theoretically providing a safe
passage across roads. Planning the location of theses crossings and to some degree their design currently does not take
into account traffic noise and light impacts on wildlife approaching the structures. The authors developed statewide
models of traffic noise and light intrusion into areas adjacent to state highways to aid understanding of wildlife responses to
noise and light and to aid locating and designing crossings to maximize wildlife approach and use. These models have the
added benefit of estimating traffic impacts as part of environmental analysis associated with delivering transportation
projects. The authors used the NoiseModeling software in QGIS and novel light-modeling tools developed in ArcGIS to
model the “noise-scape” and “light-scape” at high-resolution around California state highways. They used different
putative sources of traffic noise and light and model propagation (depending on traffic volumes) of both across adjacent
landscapes out to at least 1 kilometer. The authors tested the models in the field using transects of noise and light
measurements. The outputs were digital (raster) maps that showed the high and low impact areas.

There is a need to understand how transportation provision affects changes in travel including induced travel. Studies are especially needed in places where the increase in travel is substantial. Current research on induced travel in Tennessee has been largely lacking. Prior studies have often used the instrumental approach to isolate the effect of capacity enhancement on travel at the area-wide scale, thus, potentially masking the effect of additional capacity on a single road where improvements have been implemented. This project fills the identified research gaps. This study searches for and identifies instrumental variables at a disaggregate level to further examine the impact of changes in the transportation system on travel. This project operated at the level of individual facilities that experienced capacity enhancement such as road widening or constructing a new lane. The research conducted in this project has led to (1) obtaining local-based evidence of changes in travel after capacity enhancement implementation, (2) identifying drivers of induced travel, and (3) estimating the impact of adding road capacity on travel measured with vehicle miles traveled (VMT) via an instrumental variable (IV) approach at the facility level in Tennessee. Thus, transportation impact analyses will help planning agencies to better understand travel patterns and local transportation impacts of road capacity expansion in metro areas in Tennessee, assist with informed policy decision making, and develop regional and state transportation plans for regional and local transportation projects. The TDOT can use this
research as evidence-based estimates of travel changes in response to adding road capacity. The TDOT and regional agencies will have a better understanding of impacts of induced travel from the road capacity expansion projects and to improve performance, environmental sustainability, and direct capital investment for transportation in Tennessee.

Recycling highway construction materials and minimizing the use of virgin materials can reduce pavement life cycle costs, improve highway network conditions, conserve natural resources, and protect the environment. Although using recycled asphalt pavements (RAP) is beneficial in many aspects, aged binder in RAP gives rise to failure under repeated high axle loads and thermal effects. Thus, in Oregon, the use of RAP is currently limited to about 30% by weight of the mix.

For asphalt mixtures with a higher percentage of RAP, various strategic measures have been developed, including increased binder content, binder grade bumping, rejuvenators, and warm-mix asphalt (WMA) additives. However, selecting the most effective rejuvenators and WMA technology for
Oregon, developing methods and guidelines for choosing the proper amount of additives, and ensuring appropriate mixing to achieve high RAP mixes without compromising the performance of the asphalt pavements is crucial. In addition, practices for better managing the RAP stockpiles at the asphalt plants (including process controls) play an important role in the mix performance and need careful investigation.

This research study addressed the above-mentioned concerns through comprehensive experimental and analytical work, including the evaluation of performance, cost, and environmental benefits of using high RAP, incorporating the strategic techniques. The effect of RAP source variability, as well as inplant variability, has also been studied. Further, the results were confirmed through statistical analysis. Results of the analysis indicate that the performance of RAP mixtures depends on binder content, RAP content, and binder grade. Considering all aspects, the appropriate selection of a strategic technique could enable a 10% higher RAP than the current allowable limit in Oregon, ensuring adequate performance while lowering economic and environmental burdens.

Bridge strikes caused by over-height vehicles frequently damage steel girders and can reduce their load-carrying capacity, requiring rapid and reliable evaluation to ensure structural safety. Current evaluation practices rely on manual measurements that often require traffic disruptions and simplified assessment approaches that do not fully capture the effects of damage. In addition, finite element simulations are time-consuming and computationally intensive to develop for practical rapid evaluation. This study developed an integrated, data-driven framework for the inspection and assessment of damaged steel bridge girders. A semiautomated procedure was developed to process laser-scan point cloud data and extract displacement profiles along the girder span. Machine learning models were trained and validated using a dataset generated from finite element simulations informed by field measurements of actual bridge strike incidents to predict the residual capacity of damaged girders. Explainable artificial intelligence techniques were incorporated to interpret model predictions and identify key parameters influencing structural performance. Results demonstrated the framework’s capabilities in effectively capturing girder displacements, and for accurately and efficiently estimating the residual capacity, to support post-strike bridge evaluation. Measured girder deformations obtained from laser scanning can be used as inputs to the machine learning models for quantifying a girder’s capacity. The predicted capacity can then be incorporated into bridge rating software to compute rating factors, enabling rapid decisions on traffic restrictions and load posting. Additionally, the interpretability results can guide engineers in identifying critical design parameters and prioritizing repair actions.

The objective of this study is to evaluate whether the current SCDOT criterion requiring the roadway subgrade to be 1 ft above the design-event ditch water surface can be relaxed under selected geometric and soil conditions, particularly where larger shoulder widths and flatter side slopes increase horizontal separation between ditch water and pavement structure.

Aggressive driving is a prevalent traffic safety concern that contributes to crash risk and undermines traffic safety culture. Building on Phase 1 work that defined aggressive driving and identified promising intervention points, this Phase 2 study examined two complementary strategies to reduce aggressive driving: supporting bystanders (i.e., spouses/partners, family members, and close friends) to intervene with drivers who engage in aggressive driving, and developing and testing media messages to encourage safer driving among drivers themselves. Key informant interviews were conducted with bystanders. Findings informed the development of a three-step bystander intervention that included expressing concern and connecting to shared values. The intervention was tested with a national sample of 102 bystanders. Results demonstrated increased bystander confidence, greater use of constructive strategies, and perceived reductions in aggressive driving frequency. Participants reported that the strategies were feasible, acceptable, and helpful. Media messages were developed in three main themes: cognitive reappraisal, adaptive response, and prosocial driving. Messages were tested with 864 drivers who reported recent engagement in aggressive driving. Findings indicated that, across message themes, messages were well received, prompted reflection on driving behavior, and supported changes in perceptions related to safety and responsibility. Together, these findings suggest that engaging bystanders and deploying supportive, nonjudgmental messaging are promising, complementary approaches to reducing aggressive driving and strengthening traffic safety culture. Resources were developed: a bystander conversation guide, a community dissemination toolkit, and a messaging development resource.

Pedestrian crosswalks, bike lanes, and medians are key safety devices in a multi-modal highway network. However, there is no statewide map of these assets' locations and types. Such a map would benefit planning, maintenance, safety assessments, and network analyses for ODOT and its partners. Currently, ODOT collects asset information through site visits and surveys, which are labor-intensive and costly across the state's vast road network. GIS databases are created ad-hoc and inconsistently, often by interns. Fortunately, ODOT Engineering Automation regularly collects 3D mobile lidar data, providing geometric and radiometric information. This research reviewed state-of-the-art approaches for detecting and classifying pedestrian crosswalks, bike lanes, and medians, and developed a methodology to extract these features from LiDAR datasets for updating ODOT’s GIS platform. The approach was tested on several datasets and showed good extraction performance, requiring minimal manual cleanup. Lastly, a plan is provided for ODOT to implement this research.

This study investigated the use of co-simulation for evaluating cooperative driving automation (CDA) applications within a work zone environment. The examined use case focused on the merging maneuvers of a single CDA-equipped vehicle into either a CDA platoon or a traffic stream consisting of human-driven vehicles near a work zone with a one-lane blockage. The findings demonstrate that co-simulation can serve as an effective component of automated vehicle and CDA testing, particularly in complex and challenging environments such as work zones. The study further demonstrated that cooperative lane-changing behavior near work zones can be systematically assessed within a controlled simulation environment, and that the resulting performance measures can help identify limitations and guide improvements to existing automated and cooperative driving algorithms and control logic.

Providing safe and secure parking for the more than three million heavy trucks that move over 70% of the nation’s freight is both a local and national issue. This is especially true for a major freight hub such as Louisiana, with its freight-intensive corridors, including I-10 and I-12. Currently, there is only one parking spot for every 11 trucks in the state, and these shortages lead to illegal parking, creating safety, operational, and economic challenges that ripple through Louisiana's freight system. These include non-compliance with Hours-of-Service regulations, economic and freight inefficiencies, and quality-of-life issues for impacted communities. This report presents the results of research that evaluated truck parking conditions in Louisiana and proposes short- and long-term solutions to address these problems. This study employed a mixed-methods approach to data collection and analysis, combining a literature review that synthesized state and national policies and local zoning laws, stakeholder surveys and interviews, GIS and spatial analyses, qualitative thematic analysis, and economic modeling using IMPLAN to assess the impacts of developing truck parking facilities in Louisiana. The cost of not investing in truck parking in the state was also calculated. Data were collected from a wide range of stakeholders, including truck drivers, trucking companies, communities, local government officials, truck parking companies, and law enforcement personnel, providing the necessary input for analyzing issues related to truck parking in Louisiana. Conclusions and recommendations were developed from a rigorous analysis and interpretation of the data. Recommendations focused on identifying priority corridors and locations where optimal benefits from parking investments could be achieved, developing model language for local zoning ordinances to support increased truck parking development in the state, and identifying potential funding avenues and management matrices to help policymakers determine the best approach to financing parking investments. Findings from this study will enable decision-makers to comprehensively address the challenges of providing adequate truck parking in Louisiana, a key to improved freight efficiency, enhanced safety, and more livable communities.