Maintenance activities account for a substantial portion of the life cycle costs of a roadway and are categorized by means of performance: contract maintenance by outside forces or in-house maintenance by DOT personnel and equipment. The nature and timing of the in-house maintenance tasks can be planned based on currently available asset performance models, but estimating the cost of future work requires knowledge of the current maintenance costs and the trends in maintenance costs.
The purpose of this research was to develop a set of maintenance cost indices that can be updated annually and used to quantify trends of in-house maintenance costs. Indices were developed for the Roadside, Maintenance, Traffic, and Bridge categories of the Standing Maintenance budget. A composite index was also developed to represent overall Roadway Maintenance. The indices were developed in a fixed base, Laspeyres index form with 2014 selected as the base period. A total of 20 maintenance tasks were selected for the basket of goods and collectively accounted for 76 percent of recorded costs in the base year. The unit cost data recorded in work order records was not normally distributed and the median value was selected for use in the calculations. The total quantity for each task was also calculated from the work order records.
Work order data records from 2012 to 2015 were used to demonstrate the index calculations. A spreadsheet tool was developed to facilitate calculating and archiving index values.
