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2 CHAPTER 2 Understanding Network Performance Measurement Linking planning and operations. Increased attention has been paid to bringing operations into the mainstream System performance depends critically on how planning and project development process. Though plan- the parts fit and work together, not merely on ning and operations have traditionally been addressed sep- how well each performs independently; it arately, there is increased realization that data collected for depends on interactions rather than on actions. operations purposes also can support the planning process Furthermore, a system's performance depends and that the planning process must address operational on how it relates to its environment--the larger needs and evaluate operational solutions (e.g., incident system of which it is a part--and to other sys- management and intelligent transportation systems [ITS]) tems in that environment (Ackoff, 1980, p. 7). alongside traditional capacity solutions). This integration is considered both as part of the CMP and as part of state met- Traditionally, transportation planning and project devel- ropolitan planning more broadly. The FHWA has authored opment practice has focused on the impacts of discrete types guidebooks to address linking planning and operations at of investment strategies in relation to specific transportation both state and metropolitan levels. Corridor coalitions. Growth of corridor coalitions has goals, with goals most often tied to a modal or even functional aspect of the transportation system, funding source, or par- spurred an increase in addressing transportation system ticular transportation function. This silo-based approach to needs across long-distance corridors using a wide range of planning and project development has carried over into per- strategies (e.g., capacity additions and operational improve- formance measurement, with measures that assess individual ments) and modes (e.g., highway, rail, and transit). These investment options and do not provide a true systems-level coalitions are increasing the recognition of freight move- perspective. Federal funding programs, organizational barriers, ments and their impact on the system, especially over long- and other factors mean that performance management tech- distance corridors. niques are often applied within silos. Furthermore, although These efforts have attempted to address the multiple several transportation organizations have begun to develop impacts of transportation projects (i.e., transportation, more comprehensive performance measures that better reflect economic, environmental, and community) and an under- their diverse planning goals and objectives, measuring per- standing that traditional new-capacity projects are no longer formance for the transportation network and using measures feasible in many areas and have to be fully justified when they across various stages of the transportation planning process are considered. remains a challenging endeavor. Several recent trends in systems planning and performance measurement have begun to increase the amount of attention Network Performance paid to network- or systems-level performance measurement. Measurement Framework Though the list is not comprehensive, some of the most impor- Components of Network Performance tant examples include Define the Network Congestion management. The growth of the congestion management process (CMP) has resulted in agencies con- From the traveling public's perspective, transportation sys- sidering a broader range of strategies to tackle congestion, tems are not bounded by the jurisdictional boundaries or including, in particular, multimodal investments. functional mandates that tend to drive current planning and

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3 project development processes. These transportation system projects, in particular, are a growing component of planned boundaries are a result of transportation planning and fund- investments. These types of investments function differently ing mechanisms needed to develop, operate, and maintain by providing additional capacity through more efficient traffic transportation infrastructure within the context of a larger operations and smoother traffic flow, without requiring new regulatory and political framework. As such, a way is needed roadway infrastructure. They are multistrategy in that there to communicate performance of transportation investments are multiple approaches to achieve an agency's goals. Similar that makes sense to the system user. Network performance to challenges associated with multimodal measures, compar- measures are intended to span these boundaries in order to ing the benefits of smaller-scale investments, such as system produce a more meaningful picture of transportation per- operations projects, to larger roadway projects is hindered formance and, as a result, communicate to transportation by limitations of commonly used technical tools, which have stakeholders why particular investment strategies are chosen been developed over decades to assess the impacts of added for funding and how well they are meeting expectations. roadway capacity. The same can be said for other types of Transportation agencies already are beginning to work smaller-scale investment strategies intended to improve traf- together across jurisdictions and scales of government (e.g., fic flow and transportation efficiencies (e.g., travel demand state, regional, and local) to improve performance measure- management measures). ment. Because differences exist between various agencies' In addition to the jurisdictional, functional, and modal organizational and functional mandates, it can be challeng- factors highlighted above, network performance measures ing to develop a common set of multijurisdictional perfor- also can be applied to span the various stages of the plan- mance measures to assess the impact of the system in relation ning process, including project identification, evaluation, to mutual goals and transportation objectives. With multi- selection/programming, and development (environmental ple jurisdictions working together, the number of potential review and construction). Often, these stages of the plan- actors compounds issues (e.g., what performance data is to ning process are managed by different agencies or groups be collected, which data matters, and how data can be used within particular agencies, and the methods for perfor- to inform decision making). Yet collaboration of multiple mance evaluation at various stages can be very different. For actors can ultimately yield more meaningful and compre- example, a newly identified project may be evaluated in hensive measurements. Use of performance information terms of a congestion reduction metric, programmed for can be increased and improved through collaboration and funding based on a cost-benefit metric that may include dialogue between jurisdictions and across scales of govern- other benefits, and administered through the project devel- ment (interagency) or between individual units within an opment processes based on a project deliverability/readiness agency (intra-agency). metric. This multistage aspect is a critical dimension of net- Agencies also are increasingly setting goals to improve work performance measurement, because it links planning multimodal mobility and accessibility. Agency performance to implementation. measures already are commonly used to assess various indi- vidual modes, but most often in isolation of one another. Framework for Implementing There are challenges to measuring multiple modes across a Network Performance network, or the connectivity of modes within or between sys- tems, with the most common being technical issues associ- This handbook provides a framework and a set of scenar- ated with predicting multimodal effects of projects and plans ios to help transportation agencies define approaches and using tools limited by network scope and detail. As interagency specific performance measures to address network perfor- and intra-agency partnerships increase and tools improve, mance. Figure 2.1 presents the basic framework, building on agencies can develop and use multimodal measures to assess the dimensions identified above. The left half of the diagram a broader array of investment strategies, improve decision- indicates the dimensions and the right half describes the basic making processes, and determine if the transportation net- process for considering network performance. work as a whole is improving mobility and accessibility for The remainder of this section describes this process for all system users. A related issue is that the measures are typ- addressing network performance. ically associated with investment options that fall within a particular silo. For example, many agencies report some mea- Define the Network sure of overall congestion. However, they typically do so only in the context of roadway investments, rather than including It is important to define the network part of network per- multimodal investments. formance early in the process. Put simply, the network is the Similarly, many agencies are setting goals to provide needed combination of (1) the relevant agencies or jurisdictions-- transportation capacity through more cost-effective projects, state, regional, and local--that have existing or proposed rather than traditional roadway widenings. Systems operations infrastructure within the geographic area under consideration

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4 Network Performance Network Performance Dimensions Analysis Process Multiple Jurisdictions Define the Define the Network Partnership Multiple Modes Identify Relevant Strategies Multistrategy Identify Relevant Measures Multistage Use Measures to Evaluate Strategies Figure 2.1. Network performance measurement framework concept. and (2) the relevant transportation modes. As an agency or city congestion issues might not examine local transit but def- set of agencies begins to address a congestion problem (or a initely include intercity rail. safety, renewal, or environmental problem), considering the full set of relevant agencies and modes to include in the net- Define the Partnership--Organizing Principle work will improve their understanding of the specific prob- of the Handbook lem and the potential range of solutions. Defining the network will depend, in part, on the scale of Along with defining the network, it is important to define the problem under consideration. For example, a focus on the partnership. Who is involved and has a voice or control commuting challenges to a specific destination might con- over decisions? Though several important dimensions of sider all modes and all types of travel, while a focus on inter- network performance have been defined, the partnership

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5 dimension is used to organize this handbook. Partnerships ple, a state may want to evaluate tradeoffs across capac- refer to the forum used by a set of agencies measuring net- ity expansion and operations investments to address work performance (as well as tackling other issues). Partner- congestion. The measures and considerations identified ships are primary because nothing else can happen without in this handbook may be useful for these circumstances them. Until a set of agencies agrees on an approach and a as well. forum to make decisions, network performance measure- ment cannot take place. The specific partnership arrange- ment will respond to the conditions and questions that the Define Network-Level Performance Measures individual agencies have. Three basic types are relevant: What are network performance measures and how are they used to measure transportation network performance? 1. Single region. The most common existing partnership Though no specific definition of transportation network per- model for considering network performance is the metro- formance measures exists, the measures encompass certain politan planning organization (MPO) or other regional criteria and qualities. Network performance measures agency. MPOs provide a deliberative forum for making regional decisions. These bodies can consider the entire transportation network and tradeoffs among modes and Address the regional, state, or multistate impacts of indi- strategies. In some states, there is a similar collaborative vidual decisions; approach, at least across modes, but MPOs are more Are derived from a process that involves multiple actors common. The MPO is federally defined with require- working in collaboration; ments for inclusion. May span multiple jurisdictions, modes, investment 2. Peer-to-peer. With the growth of metropolitan areas and strategies, and stages of the plan and project development the increased recognition of multiregional and multistate process; issues, such as long-distance freight movements, a new Are connected with broader outcomes and systemwide form of partnership is emerging to address these issues. performance objectives; These partnerships are between agencies (two or more Measure the performance of a transportation network, not MPOs, or two or more states) that are peers. Network per- only individual facilities; and formance measures can be useful for supporting two dif- Are supported by data and tools that provide a fair com- ferent types of peer-to-peer partnerships: parison of different types of investment strategies. State-to-state partnerships are increasingly common through various corridor coalitions that have been established for individual projects (e.g., the I-10 Corri- Define Network Performance Strategies dor Coalition) or on an ongoing basis (e.g., the I-95 Cor- One of the key dimensions of network performance is the ridor Coalition). In addition, sets of states often develop consideration of multiple types of strategies. The significant multistate compacts to address individual transporta- cost of and lack of physical space for new transportation tion challenges. capacity (whether highway or transit) have increased the inter- MPO-to-MPO partnerships for performance measure- est in system operations solutions. Like modal silos, perfor- ment are less common, but the growth of metropolitan mance measurement has often been conducted separately for areas has increased the need to address transportation different types of strategies. Again, defining the appropriate issues across MPO boundaries. In several states, indi- strategies will depend on the scale of the effort under consider- vidual MPOs are defined by county boundaries, and the ation and the modes and jurisdictions involved in defining the true area of commuting spans these boundaries. In addi- network and partnership. tion, megaregions are increasingly spanning multiple multicounty MPOs. 3. Intra-agency partnerships. Because partnerships are Apply Network Performance Measures the organizing principle of this handbook, individual agency attempts to consider the network-level implica- Applying the network performance measures will depend tions of transportation decisions have not been the focus. on context. Examples of application may include the following: However, even within a given agency, there are often different groups with responsibilities for different pieces Corridor-level performance measures. Measure investment of the system or different types of investment. For exam- strategies across an entire corridor that spans jurisdictions