Reliable estimation of investment and life-cycle costs from road projects to single road assets

Abstract

The estimation of investment costs of road projects is a key task at every stage of planning and implementation. From the initial project idea to detailed planning and legal approval, the costs of transport infrastructures play a decisive role for investors, authorities, and the public. Although each project is different and some deviations between estimation and actual costs are to be expected, there is ample evidence from the literature on systematic underestimation and the main reasons for this effect. Beyond investment costs, reliable estimations of life cycle costs from single assets and projects up to entire road networks are of an increasing importance to determine budgeting needs, preserve asset value, and define contracts between stakeholders. In all cases, systematic methods and a large database on road projects and individual measures are needed to provide a sufficient basis for cost estimations and validation. This paper tries to fill this gap by providing unit costs both at the project and asset level for construction and rehabilitation measures with adjusted prices for the year 2022. Thereby, the cost estimates are based on extensive research and collected cost data from projects on regional roads and highways in Austria over the last two decades. In addition, the paper presents calibrated standardized live cycle costs for key road assets together with life cycle cost factors providing the means to estimate life cycle costs based on construction costs alone. Finally, the adjustment of prices for different regions and years of construction are highlighted, allowing for a validation of individual project appraisals.