Procedures for the Estimation of Pavement and Bridge Preservation Costs for Fiscal Planning and Programming

Facility preservation generally refers to the set of activities that are carried out to keep a facility in usable condition until the next reconstruction activity. For fiscal planning and programming, it is necessary to know the expected costs of preservation projects and how long they would last. Such information, coupled with minimum standards and facility inventory data enable estimation of overall monetary needs for bridge and pavement preservation, and would assist INDOT in undertaking appropriate programming and attendant financial planning over the long term. However, detailed engineering analyses are not possible every year because of the time and effort involved, therefore simple procedures to help estimate annual pavement and bridge preservation needs are useful for long-term fiscal planning. The study methodology consisted of first undertaking a full analysis based on engineering principles and detailed work in order to determine pavement and bridge needs for a period of time. Then simple procedures to estimate yearly pavement and bridge preservation costs were developed and the results were compared to the detailed engineering needs. Deterioration and cost models to establish engineering needs were developed using an array of statistical techniques including analysis of variance and regression analysis. Using the deterioration models, system inventory and minimum standards, the level of physical needs was determined for the entire pavement and bridge network over the analysis period. Finally, using the identified physical needs and developed cost models, the monetary needs were estimated. An age-based approach (that considers fixed time intervals instead of deterioration trends and minimum standards) was used for the bridge preservation needs. Based on the historical expenditure records and the amount of work performed in the past, simple regression models were developed to estimate future annual pavement and bridge preservation needs. The results obtained proved to be consistent with the engineering analysis