Mapping the patterns of cost and time overruns in the U.S. highway construction projects: a regional risk analysis

Highway construction projects are inherently complex, with time and cost as risk factors requiring effective management for successful completion. Regional factors—such as climatic conditions and workforce availability—influence cost overruns and time delays in highway projects; thus, addressing these factors through robust risk management is essential for risk mitigation. As part of that goal, this research aims to map the cost and time overrun risk patterns across various regions in U.S. highway projects and examine how transportation agencies can leverage this risk mapping. Data from 186 highway construction projects across the four AASHTO regions were analyzed statistically to evaluate the risks of time delays and cost overruns. A focus group discussion with experts was conducted to validate the findings and identify strategies for leveraging risk mapping. The findings indicated no significant differences among the four regions regarding the overall risks of cost overruns and time delays. However, the northeastern states exhibited the highest incidence of cost overruns, while the western states experienced the most considerable time delays. The southern and midwestern regions demonstrated moderate risk levels in both categories. Eight strategies were identified to address these cost overruns and time delays arising from regional factors through the risk mapping.