This research synthesized evaluation findings from 24 projects sponsored by the Federal Highway Administration (FHWA) Congestion and Value Pricing Pilot Program (VPPP) between 1991 and 2006. Strategies evaluated included:
- High-Occupancy Vehicle (HOV) to High-Occupancy Toll (HOT) lane conversions with pricing
- Variable pricing of new express lanes
- Variable pricing on existing toll facilities
- Region-wide variable pricing initiatives
- Making driver costs variable
- Other pricing projects (i.e., voluntary cash out and carshare programs).
This source report included an overall assessment of the impacts of value pricing and included detailed findings for several projects.
The body of research conducted over the last decade and a half suggests that variable pricing can reduce congestion and increase vehicle throughput. By influencing traveler behavior and impacting selected travel choices (travel times, routes, trip frequency, and mode of travel) effective pricing strategies can reduce peak-period traffic congestion, increase vehicle and person throughput, and result in more efficient use of highway capacity. The findings indicate that travelers are willing to pay for faster travel times. However, the nature and magnitude of impacts can depend on multiple factors, including the pricing concept, price levels and schedules, coverage, pricing periods, the existing traffic levels, and demographic characteristics.
HOT Lanes on I-394 in Minnesota (MnPASS)
Beginning in May 2005, HOV lanes from Highway 101 to I-94 in the Minneapolis area were converted into dynamically priced HOT lanes. The project included two sections of highway: a three mile east section that had two reversible lanes separated by a barrier from general purpose traffic; and an eight mile west section that had one lane in each direction separated by double-white stripes from general purpose traffic. Traffic heading into Minneapolis (eastbound) could use the HOT lanes facility from 6:00 AM to 10:00 AM, and traffic heading out of Minneapolis (westbound) could use the facility from 2:00 PM to 7:00 PM. The facility was free to buses, HOVs and motorcyclists during peak hours, and all users during off-peak periods.
In order to use the system, MnPASS drivers need to open a prepaid account with a credit card and then attach a transponder tag to the inside of their vehicle’s windshield. Tolls varied up to 20 times per hour depending on traffic density measured by roadway sensors in the toll lanes. Enforcement beacons were mounted above roadways and used to detect valid transponder and notify police when valid transponders were detected. Mobile enforcement readers were also used to confirm that valid transponders were engaged at previous antenna locations. Violation fines were assessed at $142.
Planning, implementation, and construction occurred from 2002-2005. Operations and evaluation occurred from 2005-present. The following preliminary findings were reported in Appendix B of the source report:
- I-394 MnPASS lanes peak-hour volumes increased by 9 to 33 percent between June and December 2005, after implementation of MnPASS.
- Despite increases in volume, travel speeds in HOT lanes have not decreased. At the same time, speeds in the general purpose lanes increased from 2 percent to 15 percent during peak rush hours.
- Preliminary performance data for I-394 MnPASS for the first six months of operations indicates the following:
- Toll trips per week (average): 17,625
- Revenue per week (average): $20,377
- Toll per trip (average): $1.16.
- A technical evaluation of the project released in November 2006 included the following key findings:
- Over 10,000 transponders have been leased by users and the average user chose to pay the MnPASS toll about twice a week.
- Before and after vehicle volumes through the corridor increased during the peak hour by up to 5 percent. This increase occurred while regional volumes in other non-MnPASS corridors observed a decrease.
- Total hours of delay in the corridor have declined appreciably since the implementation of MnPASS.
- Travel speeds increased in the general purpose lanes, as well as the MnPASS lane, providing a reduction in travel times through the corridor.
- Key findings from a November 2006 Attitudinal Study of the I-394 project indicated:
- Dynamic pricing works. Average speeds of 50 mi/hr are maintained 95 percent of the time. Survey results indicate that 85 percent of users are satisfied with the speed of the traffic flow in the MnPASS lane.
- Technology works, More than 95 percent of current customers are satisfied with the all-electronic system; 93 percent are satisfied with the credit card based system of funding accounts; 92 percent are satisfied with the ease of installing the transponder; and 87 percent reported no problems merging into the MnPASS lane.
- Broad support. Approval was consistent across all income groups. Seventy-one (71) percent higher-income, 61 percent middle-income, and 64 percent lower income indicated "strong" or "somewhat" approval of tolling. Support remained strong among carpoolers (60 percent "good idea") and stable among transit users (49 percent "good idea").
- HOV use has not changed. The current mode share of I-394 panelists is comparable to that captured in the first round surveys (pre-operation: 81 percent drive alone and 19 percent carpool).