8  Increase travel time reliability and predictability

Increase travel time reliability and predictability for travel on highway and transit systems.

8.1 Transit on-time performance

Metro Transit buses departed on-time 84% of the time in 2022. Light rail and Northstar commuter rail, departed on-time 75% and 95% of the time in the same year, respectively. On-time performance is one way to communicate transit reliability. Metro Transit considers a bus or train on time if it departs up to one minute before or five minutes after its scheduled time. On-time performance is measured at a set of stops, called time points, along each route rather than at every stop.

Metro Transit’s goal for on-time performance is generally to improve compared to the previous year. This has been challenging post-pandemic and performance decreased for buses and light rail compared to 2021. Many factors influence on-time performance, similar to those that affect roads and highways like weather conditions, large events, and roadway or rail conditions and maintenance. In addition, the operator shortage continues to limit Metro Transit’s ability to mitigate disruptions or delays to service. Learn more about the Metro Transit workforce in Section 3.1.

Figure 8.1: Annual bus and bus rapid transit on-time performance by service type and route, 2019 to 2023.

Figure 8.2: Annual light rail and commuter rail on-time performance by service type and route, 2019 to 2023.

8.2 Freeway planning time index

The Texas Transportation Institute’s (TTI) Urban Mobility Report compiles data on transportation system performance for metropolitan areas throughout the United States. These data can be used to measure changes in the performance of the Twin Cities’ highway system over time and provide a rough comparison with similar peer urban areas in the United States. These peer urban areas are Baltimore, Cincinnati, Cleveland, Dallas, Denver, Milwaukee, Pittsburgh, Portland, Seattle and St. Louis. TTI published their most recent data (2020) in 2021.

Reliability serves as a proxy for congestion, and is measured with the planning time index, represents the total travel time that should be planned for a trip to be late on only one work trip per month (1 out of 20 days). A higher planning time index indicates a greater level of congestion. According to 2017 data from the Texas Transportation Institute, the freeway planning time index in 2019 for the Twin Cities region was 1.77 for automobiles, ranked 7th among urban areas evaluated. An index of 1.77 means that for one work trip per month the total travel time will exceed 1.77 times what it takes to make the same trip in light traffic.

Peak hour excessive delay, a federally required measure, can be found in the Appendix.

Figure 8.3: Freeway planning time index from 2017 to 2019 in the Twin Cities and peer regions. Source: TTI Urban Mobility Report, 2021

8.3 Daily delay per commuter

To the typical commuter, the amount of time spent in congestion is generally more important than the number of congested freeway miles. In 2019, the average Twin Cities auto commuter spent 10 minutes delayed in traffic on an average day. In 2020, average daily delay dropped to 5 minutes mainly due to the COVID-19 pandemic. These figures account only for the two peak travel time periods, which are weekdays from 6:00 a.m. to 10:00 a.m. and 3:00 p.m. to 7:00 p.m. While delay is anticipated to increase from 2020 levels, the region has less daily delay than similar sized metro areas.

Figure 8.4 depicts the delay by year. Like its peer regions, the metro area had experienced moderately increased annual delay until 2019, when the COVID-19 pandemic substantively changed travel.

Figure 8.4: Peak hour commuter delay 2010 to 2020 in the Twin Cities and across peer regions. Source: Texas Transportation Institute Urban Mobility Report, 2021

8.4 E-ZPass Express Lanes

The E-ZPass network (previously known as MnPASS) is a system of high occupancy toll (HOT) lanes that allow high-occupancy vehicles to travel for free during congested periods of the day. Solo motorists may also choose to pay a fee to use the lanes during these periods. The average fee for a solo motorists was $0.85 in 2022.

To learn more about the daily number of people in E-ZPass lanes, see Section 2.1.

8.4.1 E-ZPass network expansion

The E-ZPass network is designed to reduce congestion during peak periods and incent carpooling and transit over single occupancy vehicles. Since its inception in 2005, the system has expanded and now includes a total of 92 lane-miles. The system is concentrated on key freeways that carry the highest volume of people. The most recent expansion is on I-35W north.

Due to its success, MnDOT is examining the feasibility of expanding the system. Corridors currently under the environmental review process include Highway 252/I-94 between Brooklyn Park and Minneapolis, and I-94 between downtown Minneapolis and downtown St. Paul. Longer-term expansion possibilities include

  • Highway 169 between Golden Valley and Brooklyn Park
  • I-35 between Lakeville and Burnsville
  • Highway 36 between Roseville and Maplewood
  • I-35W North Gateway between downtown Minneapolis and Roseville
  • Highway 77 (Cedar Avenue) between Apple Valley and Richfield

Figure 8.5: E-ZPass Miles over time

8.4.2 E-ZPass reliability

In the context of transportation, reliability refers to the consistency or dependability in travel times from day-to-day or hour-to-hour. Reliability is important to drivers and passengers as it accounts for extreme events and the intensity of congestion at particular times or on particular days, thus allowing travelers to better anticipate delays and plan accordingly.

E-ZPass lanes are far more reliable than general purpose lanes during peak periods and provide relatively consistent travel times at all times. Figure 8.6 illustrates the travel time reliability of E-ZPass lanes versus general purpose lanes along north-bound I-35W. Whereas a trip using general purpose lanes may vary in length from 12 minutes to over 18, E-ZPass lanes did not fluctuate more than minute during the course of an average day in 2021.

Figure 8.6: Travel time reliability on E-ZPass lane versus general purpose lanes