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The COVID-19 pandemic has had far-reaching impacts on public health and safety, economics, and the transportation system. To reduce the spread of this disease, federal and local governments around the world have introduced stay-at-home orders and other restrictions on travel to “non-essential” businesses to implement social distancing. Preliminary evidence suggests substantial variability in the impacts of these orders in the United States, both across states and over time. This study examines this issue using daily county-level vehicle miles traveled (VMT) data for the 48 continental U.S. states and the District of Columbia. A two-way random effects model is estimated to assess changes in VMT from March 1 to June 30, 2020 as compared with baseline January travel levels. The implementation of stay-at-home orders was associated with a 56.4 percent reduction in VMT on average. However, this effect was shown to dissipate over time, which may be attributable to “quarantine fatigue.” In the absence of full shelter-in-place orders, travel was also reduced where restrictions on select businesses were introduced. For example, restrictions on entertainment, indoor dining, and indoor recreational activities corresponded to reductions in VMT of 3 to 4 percent while restrictions on retail and personal care facilities showed 13 percent lower traffic levels. VMT was also shown to vary based on the number of COVID case reports, as well as with respect to other characteristics, including median household income, political leanings, and how rural the county was in nature.

Distracted driving is among the leading causes of motor vehicle crashes in the United States, though the magnitude of this problem is difficult to quantify given limitations of police-reported crash data. This study leveraged data from the second Strategic Highway Research Program Naturalistic Driving Study to gain important insights into the risks posed by driver distraction on both freeways and two-lane highways. More than 50 types of secondary tasks were aggregated into ten distraction type categories and mixed-effects logistic regression models were estimated to discern how the risks of near-crash events varied by distraction type while controlling for the effects of driver, roadway, and traffic characteristics. In general, the types of distractions that created the most pronounced risks were those that introduced a combination of cognitive, visual, and manual distractions. For example, drivers who used cell phones were subject to higher risks and these risks tended to be most pronounced when both visual and manual distractions were involved. Likewise, risks tended to be highest when drivers reached for other objects inside the vehicle, engaged in personal hygiene-related activities, or focused on activities occurring outside of the driving environment. Although the same factors tended to increase near-crash risk on both types of facilities, the impacts of several factors tended to be more pronounced on two-lane highways where interaction with other vehicles occurred more frequently. From a policy standpoint, the results of this study provide further motivation for more aggressive legislation and enforcement of distracted driving.

Research was conducted to assess the effectiveness of a dynamic speed feedback sign (DSFS) as a speed reduction strategy at speed transition zones along five high-speed rural highways in northern Michigan. The DSFS was positioned on the shoulder in advance of the reduced speed limit at each community and was programmed to display speeds of approaching vehicles alternating with the upcoming reduced speed limit. Using handheld LIDAR guns, vehicle speeds were tracked through each speed transition area before and after installation of the DSFS. The DSFS was found to have a significant speed reduction effect throughout each of the five speed transition zones. The speed reductions generally began when the DSFS came into the motorists’ view, and the speed reduction effect increased as motorists approached DSFS. The greatest speed reduction effects were observed at the DSFS location itself, where speeds were 3.2 to 7.8 mph lower with the DSFS present, and these reductions were sustained on entry to the community. Similarly, drivers were 78.8 to 92.4% less likely to exceed the reduced speed limit with the DSFS present. Positioning the DSFS further upstream typically resulted in earlier speed reductions, although this effect became negligible once vehicles reached the reduced speed zone entering the community. Based on the study findings, continued use of DSFS for speed management at speed transition zones entering communities on high-speed rural roadways is recommended. When used in this context, the DSFS should be positioned 250 to 650 ft upstream of the reduced speed limit.

Urbanization and population escalated Motorized Vehicles (MVs) use and caused serious environmental, health and traffic issues. These can be tackled by increasing Non-Motorized Vehicles (NMVs, walk and Bicycle) share and decreasing the MV usage. The purpose of this paper is to study the potential of NMVs usage in Rewa city (Tier 3), India. Many studies have been conducted in Tier 1 and 2 cities of India to get an insight on willingness to use NMVs but Tier 3 cities are seldom studied. This study is an attempt to explore the factors that influence NMV usage. Are these factors different from those of Tier 1 and 2 cities? Revealed Preference (RP) and Stated Preference (SP) data was collected using a paper questionnaire and both mandatory and non-mandatory trips were studied and certain MV restrictive and NMV oriented policies were asked. It was found that 27 and 11 percent of the respondents of mandatory and non-mandatory trips were currently using NMVs. It was also observed that as the age, occupation level, income level, vehicle occupancy increases the willingness to use NMVs increases and it decreases rapidly after 3kms in both types of trips. Logistic regression models were developed, to estimate the probability of willingness to use NMVs which showed an accuracy of 80 percent in the prediction of willingness level. The study gives an insight on factors influencing the NMV usage and are compared with large cities, moreover, it helps in understanding various infrastructural and policy provisions that can encourage NMV usage.

Distracted driving is among the leading causes of roadway crashes worldwide. However, due to limitations of police-reported crash data, it is often challenging to understand the nature and magnitude of this problem. Distraction has also been shown to affect driver speed selection, which is important as both mean speed and speed variance have substantive impacts on crash risk. This study utilizes naturalistic driving data to investigate the relationship between the engagement in various secondary (non-driving) tasks and driver speed selection under different driving contexts. Separate analyses were conducted for low-speed and high-speed driving environments. Two-way random effects linear regression models were estimated for both speed regimes, while controlling for driver, roadway, and traffic characteristics. The differences were assessed based upon ten types of secondary tasks. In general, engagement in all tasks was found to decrease speeds in high-speed environments while the effects were mixed in low-speed settings. The changes in speeds were much pronounced for secondary tasks that include a combination of visual, manual, and cognitive distractions, such as cell phone use. Among all secondary tasks, an average episode of a driver talking on a handheld cellphone was associated with a 6-mph speed reduction in high-speed environments, but a 3.5-mph increase in low-speed settings. In addition to examining impacts on speed selection, the risk of involvement in crash and near-crash events was also evaluated in consideration of the type and duration of distraction. Interestingly, distractions tended to show similar relationships, in both direction and magnitude, with the risk of involvement in both crash and near-crash events. From a policy standpoint, this study provides further motivation for legislation and other programs aimed at curbing distracted driving.

Increased pollution, congestion, traffic jams, higher travel cost, travel distance, travel time, accidents, and dependence on imported oil, etc., are the major problems that the countries in the world are facing today. Non-motorized transport or active transport is one of the measures to conquer such problems. The trips conducted by non-motorized modes are important because these are a very flexible solution to accessibility, especially where the resources are scarce. These are capable of generating employment and poverty alleviation. In addition to this, the total cost of non-motorized traffic infrastructure along with operating costs is 4–8 times cheaper than that needed for motorized vehicles. Studying these trips will help planners to understand the needs of non-motorized trip makers. By knowing this, one can design facilities and policies for the use of non-motorized vehicles. This paper aims to present information about the modal share of non-motorized trips, importance of these trips in present scenario, factors affecting non-motorized vehicles, and policies and design needs which can help in increasing the modal share of non-motorized trips.