The Michigan Department of Transportation is in the process of determining its position on the level of additional funding required for the Michigan state-owned (“I,” “U.S.,” and “M” roads) highway and transit systems. Determination of funding needs is part of the 25-year planning process required by the federal government and that the department is currently in the midst of. While a final funding needs analysis is not complete, interim reports have determined the backlog of highway reconstruction needed to complete and maintain the department’s 10-year goal of having freeways in 95 percent “good” condition, with non-freeways at 85 percent “good.” These measures of “good” are based on Remaining Service Life (RSL) calculations that take a different approach to roadway evaluations than the often publicly reported International Roughness Index (IRI) conditions. The differences in these systems are described more fully in a later section on Pavement Condition.
Table 5 summarizes MDOT’s estimates of 2005 state trunkline backlog need for various types of urban and rural reconstruction, resurfacing, expansion of lanes, etc. The backlog does not include county/city needs, and is over and above what can be done with available funding. In order to meet the road condition goal, as of 2005, there is a backlog of 543 lane miles of freeway and 264 lane miles of non-freeway requiring reconstruction. In addition, in order to reduce congestion to acceptable levels, at 2005 year end, there was a need for 722 lane miles of new freeway lanes (major and regular urban), and 1,387 lane miles of new non-freeway expansion. There was also a backlog of 464 state bridges needing replacement, and 331 needing major preventive maintenance. Costs per lane mile for reconstruction are in the $0.8 to $1.3 million per mile range, with capacity expansion costs ranging from $3 million to $26.6 million per lane mile. Bridge costs range from $0.6 to $1.1 million for each depending on the setting and type.
Based on the MDOT need estimates and the author’s estimates of construction costs per lane mile, there is a backlog of $13.8 billion in investment needs. This includes some $11.4 billion of lane expansion projects, $848.9 million for reconstruction, and $939.6 million for resurfacing. The expansion projects are costed assuming some 100 urban freeway miles would be at a major cost of $26.6 million per lane mile, with the remaining urban freeways (317 miles) costed at a lower rate of $10 million per lane mile. However, as MDOT notes in their report, not all of the capacity expansion will be needed given the benefit of various demand mitigations strategies. If $2 billion in lane expansion needs can be avoided, this would lower the total investment need to $11.8 billion. While new needs will continue to be added each year, the current backlog investment spending would be spread over 10 to15 years. At that rate, there is an annual need for an additional $0.787 to $1.18 billion per year. It is also important to point out that this need analysis reflects a perfect world where all needs are addressed. Some needs are greater than others and it is likely that the needs list will be prioritized each year and that some needs will never be fully addressed.