A framework for determining the impact of deferred maintenance and/or obsolescence of a highway system

In the early 1980's, the decline in the U.S. infrastructure was highlighted by a report entitled America in Ruins: Beyond the Public Works Pork Barrel. A series of reports followed trying to assess the condition of the infrastructure. One of these reports, Fragile Foundations, assigned grades to the various infrastructure systems and concluded that "the quality of America's infrastructure is barely adequate to fulfill current requirements and insufficient to meet the demands of future economic growth and development."

This research develops a framework to account for the impact of deferred highway maintenance and/or construction on user and non-user benefits. This will aid the decision-making process and help guide the effective use of scarce financial resources. The framework proposes the concept of a Comprehensive Level of Service for highways using a combination of both maintenance (Level of Operation) and capacity (Level of Availability) indicators. Highways, like equipment, are affected by deterioration and obsolescence, obsolescence being the inability to function as designed. Deterioration, defining the physical level of service, comes from the aging of physical materials over time. Obsolescence, defining the functional level of service, comes from increased usage. Together, they result in overcrowding, congestion and increased economic costs to both users and non-users.

A mathematical model is developed that allows simulation of the impact of deferred highway maintenance based on the concept of a Comprehensive Level of Service. System dynamics is the simulation methodology utilized as it allows incorporation of social, technical, economic and political issues into a laboratory setting to analyze change. The framework, permitting evaluation of the future implications of current policy decisions, is demonstrated through scenario analysis. The scenarios include an analysis of various highway maintenance investment levels and of the trade-off between highway maintenance and highway improvement. These scenarios demonstrate the impact of maintenance and construction investments on a highway system through a user and non-user benefit analysis.