A Survey of Preliminary Cost Estimating Approaches across State Transportation Agencies

A successful transportation project’s planning and execution depends on accurate cost estimation. This paper focuses on the preliminary cost estimation techniques used in transportation projects and provides the results of an extensive survey targeting transportation professionals at state departments of transportation (DOTs) in the United States. The purpose of the survey is to learn about the practices, methodologies, tools, and challenges associated with preliminary cost estimation as it is employed across various states. The survey’s methodology and participant demographics are covered in full in the first section of the paper. The survey findings are then explored in detail, indicating the variety of practices employed by DOTs in terms of estimation methods, data sources, and degrees of satisfaction with the current procedures. It also emphasizes the types of estimating tools utilized, the procedures applied to contingency cost estimation, and whether agencies adhere to federally authorized approaches. The research further investigates how agencies handle unit costs, inflation, and cost indices, offering light on regional factors. About 36% state DOTs responded to the survey, and according to the survey, there was no federally prescribed preliminary cost estimating approach and the most common tool was Excel-based tool. It is clear from the survey responses that there is wide variation in practices across the various state DOTs. This study contributes to the field of transportation project management by offering the current state of practice when it comes to preliminary cost estimating approaches for transportation projects. The paper also presents future directions for developing risk-based cost estimating approaches that are suitable for practical usage.