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

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40 C h a p t e r 6 6.1 Study area The Southwest Corridor Plan, which is illustrated in Appen- dix A, integrates multiple efforts: local land use plans to iden- tify actions and investments that support livable communities; a corridor refinement plan to examine the function, mode, and general location of transportation improvements; and a transit alternatives analysis to define the best mode and alignment of high-capacity transit to serve the corridor. The plan is a part- nership between Metro, Multnomah County, Washington County, the Oregon DOT, TriMet (the Portland region transit agency), and the cities of Portland, Sherwood, Tigard, Tualatin, Beaverton, Durham, King City, and Lake Oswego. The project uses a technical advisory committee, a project team leaders’ group, and a steering committee made up of representatives of local jurisdictions to advise and contribute to the process. A project map of the Southwest Corridor Plan is shown in Figure 6.1. 6.2 Descriptions of Scenarios Scenarios analyzed by this study are described as follows: • Scenario 1. This scenario included only the base network without any BRT or intelligent transportation system strat- egy. No reliability measure was modeled; that is, DynusT and FAST-TrIPs assignments were based entirely on travel time without incorporating travel time reliability. • Scenario 2. This scenario was similar to Scenario 1 except that reliability measures were included. • Scenario 3. This scenario incorporated BRT into the base network on Barbur Boulevard operating in mixed traffic. This scenario was equivalent to a typical transit route, but with improved bus frequencies and fewer stop locations. These alterations represented a minimal improvement to the transit service within the corridor without any change in existing transit or auto right-of-way (ROW). • Scenario 4. This scenario was similar to Scenario 3 but with BRT operating in a dedicated ROW by taking up one existing lane. • Scenario 5. This scenario was similar to Scenario 3 but with BRT operating in a dedicated ROW by adding one lane. • Scenario 6. This scenario was Scenario 3 with the addition of several variable message signs (VMSs) along Barbur and I-5. • Scenario 7. This scenario was Scenario 4 with the addition of several VMSs along Barbur and I-5. • Scenario 8. This scenario was Scenario 5 with the addition of several VMSs along Barbur and I-5. Scenarios 9 through 15 were similar to Scenarios 2 through 8 with reliability measures not being considered. All scenarios are summarized in Table 6.1. Cross sections of the scenarios are shown in Figures 6.2 through 6.4 to better illustrate their differences. BRT line coding and the VMS locations along the Southwest Corridor are shown in Figures 6.5 and 6.6, respectively. 6.3 Scenario Coding Scenarios 3, 4, and 5 included the following adjustments to the local bus network in coordination with BRT service: • Route 12 frequency was reduced between Tigard and downtown Portland where BRT service operates. • Route 76 was rerouted from SW Hall Boulevard to SW 72nd Avenue in Tigard to avoid duplicating BRT routing. • Route 94 frequency was increased between Sherwood and Tigard. In all the scenarios beyond the first two—which were essen- tially the base network—modeling the scenarios entailed cod- ing the BRT plus “Other Buses” changes into the DynuStudio FAST-TrIPs base network. After running the new transit cod- ing in FAST-TrIPs, the standard DynusT model was run to Scenario Descriptions

41 Figure 6.1. Southwest Corridor project map. Figure 6.2. Cross sections of Scenarios 1, 2, 3, and 6. Figure 6.3. Cross sections of Scenarios 4 and 7. Table 6.1. Scenario Summary Scenario Reliability Interaction with Other Traffic Existing or New Lane VMS 1 No na na No 2 Yes na na No 3 Yes Mixed with Traffic na No 4 Yes Dedicated Lane Existing No 5 Yes Dedicated Lane New No 6 Yes Mixed with Traffic na Yes 7 Yes Dedicated Lane Existing Yes 8 Yes Dedicated Lane New Yes 9 No na na No 10 No Mixed with Traffic na No 11 No Dedicated Lane Existing No 12 No Dedicated Lane New No 13 No Mixed with Traffic na Yes 14 No Dedicated Lane Existing Yes 15 No Dedicated Lane New Yes Note: na = not applicable.

42 Figure 6.4. Cross sections of Scenarios 5 and 8. Figure 6.5. Southwest Corridor BRT line coding.

43 Figure 6.6. Variable message sign (VMS) locations. Run FAST TrIPs to produce dwell time information for DynusT Run DynusT to produce transit schedule and stop time information for FAST TrIPs Run FAST TrIPs Figure 6.7. Scenario coding flowchart for Scenarios 1 and 2 (base network). Run FAST TrIPs to produce dwell time information for DynusT Run DynusT to produce transit schedule and stop time information for FAST TrIPs Run FAST TrIPs Add Bus + Other Buses coding to transit system Figure 6.8. Scenario coding flowchart for Scenarios 3 and 6 (BRT in mixed traffic). create the transit schedule, which was then fed into FAST- TrIPs. The process generally followed the steps shown in Figure 5.8. The flowcharts of Figures 6.7 and 6.8, respectively, show the coding process for Scenarios 1 and 2 and Scenar- ios 3 and 6. For Scenarios 4 and 5 (and similarly for Scenarios 7 and 8), the process varied slightly, as these scenarios assumed that BRT runs on a separate ROW dedicated solely to high-capacity transit. In these scenarios, instead of coding ROW directly, DynusT was run twice. The first run was with very little demand to simulate the situation that buses were traveling in free-flow conditions, and the second run was with full demand to simulate buses traveling in full-demand conditions. After these two separate DynusT runs were completed, the two AltTime_Transit.dat files were used to produce the FAST-TrIPs transit schedule. The file from the full-demand DynusT run was used for coding transit for the entire system, and the BRT coding section was substituted from the results of the free-flow DynusT run. This coding reflects a bus running in a dedicated ROW and was fed into FAST-TrIPs. The coding for these sce- narios is illustrated in Figure 6.9. Although different services (e.g., bus, BRT, rail) may be run separately in DynusT, or if some routes are not simulated (e.g., rail) and so are separate, all the routes should be pro- vided to FAST-TrIPs in a single file (ft_input_stopTimes.dat). 6.4 Model Feedback Framework The feedback framework implemented for this project as shown in Figure 6.10 started from initial DynusT and FAST- TrIPs assignment to obtain skim (zone-to-zone travel time) information. The skim information was then returned to the mode choice model in the Metro TDM to estimate the mode shift due to the change of skim data that resulted from the initial assignment. The new estimated demand informa- tion for all the modes was then fed into DynusT–FAST-TrIPs again as the final assignment. The results reported here are from the final runs.

44 Figure 6.9. Scenario coding flowchart for Scenarios 4, 5, 7, and 8 (BRT in dedicated right-of-way). Figure 6.10. Feedback framework.