Value of Travel Time Reliability in Transportation Decision Making: Proof of Concept—Portland, Oregon, Metro (2014)

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52 C h a p t e r 8 8.1 Second Workshop Summary The research team organized the second workshop and shared the research findings with the policy group on March 27, 2014, at Portland Metro from 10:30 a.m. to 1:30 p.m. Sixteen attend- ees participated in this workshop. Attending agencies included the Oregon DOT, Metro (a metropolitan planning organiza- tion), City of Tigard, Washington County, City of Sherwood, and City of Portland. Attendees also included two SHRP 2 staff members. The workshop’s participants included the following: • Policy Group 44 TriMet (regional transit authority) 44 Oregon DOT 44 Washington County 44 Metro 44 City of Tualatin 44 City of Portland 44 City of Tigard • Workshop Observers 44 Project supervisory team, Transportation Research Board 44 Metro • SHRP 2 L35 Project Team 44 University of Arizona 44 Metro 44 RST International Inc. The workshop presented the research outcomes to the policy group by describing the research and by answering the general question “How does reliability measurement affect decision making in the planning process?” • Overall framework of the research • Data collection: stated-preference approach to determine value of reliability • Tool and model building 44 DynusT and reliability calculation 44 FAST-TrIPs and reliability calculation 44 Integration of reliability into the TDM • Scenario development • Tool application methodology 44 Schematic 44 Reliability impact on paths The workshop included open discussions and a consider- ation of the question “Does information regarding reliability derived in this manner assist you in decision making?” The policy groups listened to all the presented outcomes and engaged in lively discussions about the modeling process and analysis results. The takeaway from the group discussions can be summarized as follows: • The policy group agreed that this project demonstrated that including reliability in modeling and analyzing various competing investment scenarios was a useful and informa- tive process. • The sensitivity and order of magnitude of change of model ridership and scenario performance appeared to be intuitive. • Given the usefulness of the methodology, the next question was how to present reliability-related information to policy makers and the general public. The process of disseminating such methodology and information remains a challenging issue and needs to be addressed in future modeling efforts. • This methodology can greatly contribute to the cost-benefit analysis for most project analyses. Examples presented in the workshop, like adding a lane or taking an existing lane to accommodate BRT, have significant cost implications, and the results show that the presented methodology has a suffi- cient level of sensitivity to support a more robust cost-benefit analysis. The value of reliability, which until now could not be communicated in a quantitative manner, needs to be highlighted in the communication with stakeholders. Policy-Maker Engagement Workshop

53 • Oregon DOT indicated the usefulness of this methodology to help them better quantify the benefit of operations improvement strategies based on a constrained budget. • The group wanted Metro to undertake a larger-scale stated- preference survey of the entire Metro panel to reconfirm the estimated value of reliability obtained in the earlier phase of this project. • A policy group member asked about additional resource requirements for an L35A type of study. After the discus- sions, a consensus was reached that the decision needs to be driven by the modeling needs and questions and that such information should be used to identify the best tool and process to meet the requirements, as well as to justify the time and resource needs for a more sophisticated mod- eling methodology, such as L35A. Although it took the research team nine months to complete this study, most of the time was spent in the initial model building. Future modeling exercises will require much less time, and the Metro staff has acquired practical experience in this effort. Metro felt studies of this nature are a worthy investment of time and effort for an agency to undertake. • Current methodology includes a certain relationship between congestion and reliability and to some extent “predicts” reliability based on a travel time measure. It is highly desirable that Metro use actual traffic data acquired from the third-party provider to calibrate the prediction model so that the model can better represent the reliability measure for the Portland region. By doing so, Metro will have a better approach for forecasting future-year reliability. • The group recognized that rapid advancement of vehicle and communication technologies will effectively reduce highway accidents and consequently reduce this source of unreliability. Nonetheless, the group also recognized the challenges in predicting all future technology-driven improvement and how such advances may affect future impacts on reliability. 8.2 Verifying Shrp 2 L05 Literature review Combining the first and second workshop outcomes, the research team also reviewed and verified the literature review reported by the SHRP 2 L05 research team (Cambridge Systematics 2013b). The L35A team’s comments regarding the L05 literature review are summarized as follows: 1. The traveler cares about reliability. The L35A team con- firmed that this statement has repeatedly been confirmed by policy groups and other research participants. 2. Agencies monitor travel time reliability, but many do not yet use it in planning. The L35A team also confirmed this statement. In the Portland region, the L35A project is the first of this kind of effort to demonstrate the methodology for incorporating reliability into project analysis, and the research team and policy groups reiterated the need for such a methodology, modeling practice, and policy-maker engagement. 3. There are several sources of travel time data for estimating a reliability performance measure. In the Metro region, the agencies have access to Oregon DOT and Metro data that have been collected continuously for years. More recent data from sources such as INRIX or TomTom expand the breadth and depth of data accessibility for Metro. 4. Operations can be incorporated into the planning process. The scenarios analyzed in the L35A project included VMS scenarios. The analysis results demonstrated how that modeling framework and approach exhibit reasonable sensitivity for capturing the performance and benefit of operational strategies. The results of the modeling exercise produced insights about operational strategies. 5. Long-range transportation planning models cannot fore- cast reliability. The Metro modeling staff and policy group both recognized the limitation of the traditional trip- based planning method. 6. Reliability can be monetized. This L35A research adopted a survey approach that allows an agency to obtain an esti- mate of the value of reliability in a cost-effective manner. The value of reliability is found to be 0.82 times the value of travel time; this value is comparable to findings in the literature. The proposed method allows an agency to solicit responses through a stated-preference method from a large group of the general traveling public, permit- ting a cost-effective estimate of a value of reliability mea- sure for the modeling exercise.