Evaluation of Impacts Due to a Bridge Closure: A Case Study of the Mississippi River Bridges in Arkansas

The TRC 2303 report presents a comprehensive analysis of the impacts of bridge closures across the Mississippi River in Arkansas, focusing on four key crossings: I-40, I-55, HWY 49, and HWY 82. Prompted by the emergency closure of the I-40 Hernando de Soto Bridge in 2021, the study evaluates both full and partial closures to quantify economic, safety, and mobility consequences. Using ARDOT’s Road User Cost (RUC) framework and the Arkansas Statewide Travel Demand Model (ARSTDM), the report estimates daily costs and system-level changes in Vehicle Hours Traveled (VHT) for autos, single-unit trucks (SUT), and tractor-trailer trucks (TTT). Partial closures of high-volume bridges like I-40 and I-55 result in substantial daily costs, e.g., up to $2.4 million for I-40 along with widespread VHT increases. This is especially so for TTT, for which 6,902 miles of roadway exhibited more than a 4% increase in VHT under the I-40 closure scenario. In contrast, HWY 49 and HWY 82 closures had more localized effects, with HWY 82 showing the highest auto and SUT impacts but minimal freight disruption. Waterway disruption costs, derived from Automatic Identification System (AIS) data, also rose sharply between 2021 and 2024, with HWY 49 carrying the highest vessel volumes and HWY 82 showing the fastest growth. To support planning, the study delivered a web-based Bridge Closure Impact Analysis Tool that automates cost calculations and visualizes impacts. Mitigation strategies include operational measures, maintenance practices, and planning-based approaches, with partial closures recommended where feasible. Overall, the report equips ARDOT with data-driven tools to prioritize investments, manage emergencies, and maintain transportation resilience across river crossings.