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This work simulates the long-term land use and transportation impacts of upzoning in the region of Seattle, Washington at the parcel level, using UrbanSim and an agent-based travel demand model (SoundCast). Scenario results are compared to illuminate differences in a Business-as-Usual (BAU) future versus two upzoning scenarios that upzone all single-family-use residential parcels in the region or just those in the City of Seattle to 3 dwelling units per parcel. Under BAU, affordability falls 20% and rents rise 6% between 2014 and 2050, as the regional population grows to 5.7 million. With regional upzoning, 68,400 more dwellings are added, with rents 10% lower compared to the BAU future. The housing affordability index falls from 75.3 to 67.31, a significant improvement over the BAU scenario's sharper fall to 60.6. If only the City of Seattle upzones, only 3,400 additional units are predicted, but rents are 5.2% lower than the BAU case. [ABSTRACT FROM AUTHOR]

This study investigates various risk factors associated with pedestrian crash occurrence and injury severity based on 78,497 reported pedestrian-involved crashes across Texas from 2010 through 2019. Crashes are mapped to over 708,738 road segments, along with road design, land use, transit, hospital, rainfall, and other location features. Negative binomial models examine the association between pedestrian crash frequency and various contributing factors, and a heteroskedastic ordered probit model investigates the severity of injuries at the individual crash level. Results from this study show the practical significance of microlevel variables in predicting pedestrian crashes. Proximity to schools and hospitals and presence of transit are all associated with higher pedestrian crash frequencies yet are rarely included in other models. Total pedestrian crash and fatal crash counts rise with the number of lanes, population, and job densities, though greater median and shoulder widths provide some protection. Higher speed limits are associated with lower crash frequencies but more deaths. Pedestrian crashes are more likely to be severe and fatal at night (8 p.m. to 5 a.m.), without overhead lighting, and when involved pedestrians and/or drivers are intoxicated. Use of light-duty trucks also significantly increases risk of severe or fatal pedestrian injury. Though newer vehicle safety features may be argued to lower crash severity or protect vehicle occupants, newer crash-involved vehicles in Texas are not found to deliver less severe pedestrian injury. Pedestrian and driver characteristics—both age and gender—are practically (and statistically) significant. Injury severity rises with pedestrian age, yet younger and/or female pedestrians on straight roadways, off the state (and interstate) highway system, and in the presence of a traffic control device (stop sign or signal) are less likely to be seriously injured, on average. Findings underscore the benefit of enhanced vehicle safety features for pedestrians, campaigns against driving and walking while intoxicated, improved roadway design, enforcement of safety countermeasures near schools and bus stops, and installment of additional traffic controls and streetlights wherever more pedestrians exist. [ABSTRACT FROM AUTHOR]

The emissions and human exposure impacts of electric vehicle (EV) adoption, especially in comparison to conventional gasoline- or diesel-powered engines, depend on numerous factors including geography, electricity generation, and fuel mix. Results of any analysis also vary depending on the nature of data collected and their level of aggregation by time or location. This paper combines several approaches to develop a robust estimate of these impacts specific to the state of Texas by considering marginal emissions by time of day, as well as location of vehicle and power plant emissions. The authors estimate health and other external costs of operating an EV in the state at approximately $62 per year, compared with an average of $136 for a passenger car powered by gasoline. [ABSTRACT FROM AUTHOR]

Motorcycles are an important form of personal transportation used by many Americans. They provide an enjoyable recreational opportunity for many and a convenient, functional mode of transportation for others. However, U.S. motorcycle crash rates are 68% higher (per vehicle-mile traveled [VMT]) than those for other vehicles, and their fatal crash rates are more than 28 times higher. This investigation examines the riding and crash experiences and safety perceptions and recommendations of 238 U.S. motorcyclists. Top rider recommendations to other motorcyclists are to wear a helmet, to avoid riding under the influence (of alcohol or drugs), and to obtain motorcycle training. Ordered probit model results for helmet-use prediction suggest that those who ride on a daily or weekly basis and have received formal motorcycle training are more likely to wear a helmet. Other results show that rider training is most common among those who wear a helmet, ride on a weekly or monthly basis, and ride to and from work, school, and/or errands. Negative binomial model results for crash count experiences suggest that long-distance riders and those with criminal convictions are at greater risk of crashing than others, whereas those who have not received motorcycle training are less likely to have been involved in a crash at some point in their riding history. [ABSTRACT FROM AUTHOR]

This article explores the traffic, land use and welfare impacts of road pricing in the Austin (Texas, USA) region, including the introduction of planned toll roads, bridge tolls, and a downtown cordon toll. Different tolling strategies are examined, including fixed versus variable toll rates. The travel demand model (TDM) incorporates joint mode and time-of-day choice models, as well as multinomial model of destination choice, relying on a full feedback of travel times and costs. Austin-calibrated DRAM-EMPAL models are used to predict future household and job distributions. Results include traffic redistribution over space and time, long-term location choice changes, and traveler welfare implications. While the proposed toll roads to generate revenues and enhance traveler options, their estimated project costs are not estimated to exceeds such benefits. In addition, the bridge tolls are expected to successfully redistribute traffic, while the downtown area appears highly sensitive to cordon tolls. [ABSTRACT FROM AUTHOR]