A Systems Approach to Pedestrian Safety, PHASE II: Using System Dynamics Tools to Examine Congestion Pricing Policies

University Transportation Centers Program2021PDFTech ReportNaumann, Rebecca BSingichetti, BhavnaKuhlberg, JillSabounchi, Nasim SLich, Kristen HassmillerSandt, LauraMarshall, SteveUniversity of North Carolina at Chapel HillCity University of New YorkCollaborative Sciences Center for Road SafetyUnited States. Department of Transportation. University Transportation Centers (UTC) ProgramUnited States. Department of Transportation. Federal Highway AdministrationCollaborative Sciences Center for Road SafetyUnited StatesNew YorkCongestion pricingPedestrian safetyPolicy analysisSimulationTravel demand managementSpeedPedestriansSafetySystemsCongestionCordon PricingZone PricingBibliometricSimulation ModelingSystem DynamicsCSCRS-R21Collaborative Sciences Center for Road Safety (Grant #: 69A3551747113)Final report (August 2019-July 2021)Pedestrian deaths in the U.S. have increased substantially over the last several years. Between 2009 and 2019, the number of pedestrian deaths increased 51%, from 4,109 to 6,205. The majority of these deaths (82%) occurred in urban areas. In a previous project (Phase 1 of this work), we engaged a diverse range of experts familiar with different aspects of pedestrian injury and death in the application of qualitative systems science tools to explore hypothesized and interconnected factors underlying the overall increase in pedestrian death rates. Detailed maps were created to depict these interconnections and clearly lay out the hypothesized mechanisms causing pedestrian death increases. The overall goal of this Phase 2 project was to develop a quantitative system dynamics simulation model that could be used as a learning tool to explore the pedestrian safety impacts of specific, current policy approaches in a defined U.S. setting. Given the recent focus and proposed implementation of congestion pricing policies in theU.S. (and specifically in New York City), we chose to explore the pedestrian safety impacts of these policies, illustrating how system dynamics tools can be used to create virtual learning environments and explore potential system-wide effects of policies prior to implementation. To inform the model we also completed a bibliometric analysis of congestion pricing policy research broadly, as well as a detailed review of congestion pricing policy studies focused on safety impacts. These reviews and analyses illuminated several key gaps for future research consideration, including gaps in equity considerations of these policies, policy impacts on specific road user types (e.g., pedestrians, bicyclists), and safety impacts for all road users. Our system dynamics model leveraged findings from these detailed reviews, as well as findings from Phase 1 of this work and a variety of data sources from New York City to examine potential congestion pricing policy impacts on pedestrian safety. We explored a variety of congestion pricing policy-related scenarios, examining differences in how such policies might be configured and revenue invested. While several of the policy scenarios resulted in similar congestion reductions, there was considerable variation in the pedestrian injury outcomes by scenario type. Some scenarios (e.g., scenarios that discontinued or reduced pedestrian infrastructure support or increased charges on for-hire vehicles) had deleterious effects on pedestrian injury counts, while others (e.g., scenarios investing a proportion of policy revenue in pedestrian infrastructure improvements pre- and/or post-policy implementation) offered improvements in pedestrian safety. A key policy take-away from this work is that a CPP combined with other pedestrian efforts has considerable potential for positive gains in public health.140