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5 CHAPTER 2 Interstate Asset Management Framework 2.1 Asset Management Overview tional comparisons. Also, note that as a measure of roughness of the pavement surface, IRI does not necessarily provide Part of the challenge of managing the IHS lies in developing an indication of the condition of the underlying pavement cost-effective investment strategies with measurable outcomes structure or substructure. that are mutually agreed upon by agency staff and external Clearly the system owners of different portions of the cor- stakeholders for managing the various assets on the system. ridor shown in Figure 2.1 must consider different factors as Assets need to be managed collectively by asset type, as well as they determine how best to manage their portion of the IHS, by segment, by corridor, by region, and for the system in its en- illustrating the fact that there is no "one size fits all" solution tirety. The challenges only will grow greater as the system ages, to measuring and managing the system. The IHS is of na- and there are more increases in passenger and freight traffic. tional importance, but management of the system must be A hallmark of the IHS is that it was initially constructed to based on balancing challenges at the state, corridor, and local conform to consistent design standards. However, individual levels. An objective approach addressing the needs at these segments of the system now face very different realities result- varying geopolitical levels is essential if the vital interests of ing from factors such as varying physical condition, age, traf- each are to be considered in a rational way. fic characteristics, operating environments, weather, design Transportation asset management is a developing field that standards, and the diverse approaches to operating and main- provides a set of tools and techniques for managing infrastruc- taining the system that have been employed at the state level. ture assets. Asset management is, at its core, a set of guiding Figure 2.1 demonstrates how the variations in condition principles and best practice methods for making informed on the IHS are manifested over a typical corridor based on transportation resource allocation decisions, and for improv- analysis of data from the Highway Performance Monitoring ing the accountability for these decisions. AASHTO defines System (HPMS). The figure plots the Average Daily Traffic asset management as follows (1): (ADT) and pavement condition over one of the cross-country interstate corridors. Variations in ADT are plotted on the Transportation Asset Management is a strategic and system- vertical axis, while International Roughness Index (IRI) atic process of operating, maintaining, upgrading, and expand- ing physical assets effectively throughout their lifecycle. It focuses ranges are shown using different colors. As indicated in the on business and engineering practices for resource allocation and figure, there are significant variations in both traffic and pave- utilization, with the objective of better decision-making based ment condition over the length of the corridor. There are upon quality information and well defined objectives. peaks in traffic levels in several areas of the corridor where the highway passes through urban areas, with particularly high The core principles of asset management have increasingly levels at approximately 700 miles. Pavement conditions are gained acceptance in the transportation community since generally very good (IRI less than 60) or good (IRI between they were initially described in the AASHTO Transportation 60 and 95). However, conditions appear to worsen as one Asset Management Guide (2). These principles hold that asset progresses through the corridor (right side of the graph), management is: based on the increasing occurrence of sections classified as "acceptable" (values between 95 and 170) or "unacceptable" Policy-Driven. Resource allocation decisions are based on (IRI greater than 170). Note that IRI is measured and reported a well-defined and explicitly stated set of policy goals and somewhat differently from state to state, complicating na- objectives.

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6 AADT (vehicles per day in Thousands) 350 300 250 200 150 100 50 0 0 100 200 300 400 500 600 700 800 900 1,000 1,100 1,200 1,300 1,400 1,500 1,600 1,700 Distance Along Corridor (miles) Very Good Good Acceptable Not Acceptable Figure 2.1. Traffic levels and pavement conditions along an interstate corridor. Performance-Based. Policy objectives are translated into internal stakeholders across an agency must define its basic system performance measures that are used for strategic goals and objectives, translating these into a set of performance management and tied to the resource allocation process. measures and targets. This step must be performed factor- Reliant on Analysis of Options and Tradeoffs. Decisions ing in available information on funding levels and customer on how to allocate resources within and across different expectations, and considering the perspectives of all internal types of investments are based on an analysis of how dif- and external stakeholders. Customer expectations are of partic- ferent allocations will impact the achievement of relevant ular importance for management of the IHS, given the impor- policy objectives. tance and level of use of the system. Customers of the system Focused on Yielding Decisions Based on Quality Infor- may be interpreted to include stakeholders in the resource allo- mation. The merits of different options with respect to an cation process (e.g., Metropolitan Planning Organizations and agency's policy goals are evaluated using credible and cur- other planning partners, Federal agencies, and resource agen- rent data. Where appropriate, decision support tools are cies), the traveling public, and private sector freight carriers. used to provide easy access to needed information, to as- sist with performance tracking and predictions, and to per- Analysis of Options and Tradeoffs. Once an initial set of form specialized analysis. goals and objectives has been established, the next step is to Reliant on Monitoring to Provide Clear Accountability analyze options and tradeoffs. In this step, analytical tools are and Feedback. Performance results are monitored and re- used to systematically analyze the impact of different budget ported. Feedback on actual performance may influence levels for a specific set of assets and activities. Note that this agency goals and objectives, as well as resource allocation iterative step is both informed by and informs the develop- and utilization decisions in future budget cycles. ment of policies, goals, and objectives. As analyses are per- formed, an agency may realize the need to revisit its goals, Figure 2.2 summarizes the basic asset management process, objectives, and performance targets. This step establishes the highlighting issues of particular importance for the IHS at concept of an asset management approach that provides each step of the process. The following paragraphs discuss decision-making transparency to the framework development. these steps. Resource Allocation Decisions. Analysis of options and Policy Goals and Objectives. The first step of the process tradeoffs typically results in a target funding level by asset type is to establish agency policy goals and objectives. In this step, and/or treatment, and a set of prioritized candidate projects