CHAPTER 5. CASE STUDIES OF HOT LANE CONVERSION PROJECTS
The purpose of this chapter is to identify lessons learned from three
case studies of HOV to HOT conversion projects:
- I-15 Express Lanes (San Diego, CA)
- MnPass (Minneapolis, MN)
- I-25 Express Lanes (Denver, CO)
Figure 5-1: Location of Hot Lane Case Studies
These three case studies were chosen to supplement the growing body
of research exploring the relationship between program objectives, system
design, concept of operations, toll collection strategies and operational
requirements. Each case studies attempts to identify outcomes (intended
and unintended) based on specific operational choices and address key
lessons learned, or best practices in the planning, design and implementation.
5.1 Data Collection Approach
Information available form published data for each of the operational
case study sites was integrated with focused interviews conducted at
the project site, when possible. To provide a common baseline, or starting
point for the interviews, a focused interview guide was developed to
facilitate in-depth probing of key project development issues and challenges
in four main areas, including:
- Public Outreach and Communications
- Planning and Policy
- System Design Procurement
- Management & Operations
5.2 Focused Interviews
The three systems were specifically chosen for the case studies because
they were converted from HOV lanes to HOT lanes or were in the planning
process for expanding existing facilities to HOT lanes and had been
operational for at least one year.
On-site interviews with the management and operations staff were conducted
at the I-15 Express Lanes in San Diego, California and MnPass in Minneapolis,
Minnesota. For I-25 Express Lanes in Denver, Colorado, remote discussions
were conducted with key management staff. As mentioned previously, the
interviews were designed to address specific issues and challenges faced
at each stage of project development to include public outreach, planning,
design, implementation and operations. Tables 5-1 and 5-2 provide a
comparative summary comparison of the three operational case sites key
site properties and operational characteristics.
Table 5-1: List of Desirable Elements
||# Access Points
||GP - ML Separation
|| 11 mi
|| 8 mi - SLn
3 mi - 2 Ln Rev.
| Multiple - SL
Rev. Entry / Exit
| 7 WB 6 EB
|| Double White, Rev. with Barrier
|| 8 mi
|| 2 Ln Rev.
||Entry / Exit
|| Rev. with Barrier
| 12 mi
|| 2 Ln HOT
|| Double Yellow, Movable Barrier
||3 mi SLn
7 mi 2 Ln Rev.
| Entry / Exit
|| Double White, Rev. with Barrier
Note: I-15 HOT expansion includes four lanes (two in each direction),
with movable barrier separation in southern section and double yellow
strip separation in northern section between HOT and general use lanes.
Table 5-2: Operational Characteristics
||Hours of Ops
|| SL HOT
| AM Peak
| 2 axle, HOV+2 Buses
|| Only SOV
|| R2L HOT
|| AM Peak
|2 axle, HOV+2 Buses
|| Only SOV
| AM Peak
|Trucks, HOV+2 Buses
|| Only SOV
The following sections briefly summarize the key findings from the
focused interviews for each of the operational sites, SANDAG’s
I-15 Express Lanes, MnDOT’s MnPass, and CDOT’s I-25 Express
5.3 San Diego, CA I-15 Express Lanes
The I-15 Express Lanes (FasTrak) opened in January 1997 as a three
year value pricing demonstration that has been operational since transitioning
from HOV only to HOT Express Lanes in January 2000. The original facility
was an 8-mile, two lane, reversible HOV facility. With over 10 years
of operational experience, SANDAG will expand the existing reversible
facility to four bi-directional HOT lanes with multiple intermediate
access locations of over 20 miles in length.
5.3.1 Project Objectives
- Provide additional highway capacity on what had been a largely
underutilized HOV facility.
- Provide better management and utilization of the HOV lanes.
- Achieve and maintain LOS C or better.
- Generate enough revenues to support ongoing operations and maintenance.
- Support new express transit service through toll revenues.
- Improve highway and transit in the corridor.
- Extend the original reversible lane segment to include and additional
12 miles of converted HOV lanes into an HOT corridor.
5.3.2 Concept of Operations
- The reversible section was operational only during the AM and PM
peak periods and closed during the non-peak period.
- As the facility expands operations for both HOV and HOT will be
24/7. System will use movable barriers on the new extension.
- As with the existing reversible sections, HOV 2+ and transit will
travel at not cost (free) while SOVs will be tolled for use of the
facility. Trucks will not be permitted to use the facility.
- Current policy only requires SOV users to have a transponder. However,
transponder use for HOV users is under consideration.
- While under consideration, there is currently no electronic enforcement,
only manual enforcement provided by enforcement officers.
- Dynamic Pricing has been employed from the initial pilot system.
Toll rates vary, on average from $.50 to $4.00 with a maximum of $8.00.
5.3.3 Innovative Project Features
- Having local and state leadership engaged in discussions early
and often throughout the planning and design phases.
- Using dynamic pricing with adjustments based on time of day, congestion
levels, and travel time differential with the general purpose lanes.
Rates may be adjusted every 6 minutes.
- Sharing revenues with BRT in corridor widely accepted by transit
agencies and the public.
5.3.4 Major Project Challenges/Mitigation Actions
- Higher risk of SOV use violations with continued manual enforcement
by CHP – Prior to the expansion of the I-15 Express Lanes, enforcement
was easier because it was a reversible lane facility that allowed
access at a single toll point, with wide shoulders and one enforcement
area. With multiple access points and limited shoulder widths, mobile
enforcement will be needed to effectively target toll violations.
- The implementation of dynamic pricing required both local public
and political support. Early and frequent (on-going) public awareness
initiatives that included public outreach, active marketing and surveys
contributed to the ready acceptance of dynamic pricing.
5.3.5 Major Lesson Learned
- Enlist the support of a strong political champion at both state
and local levels to provide advocacy for HOT lane conversion.
- Roll out an extensive public outreach program involving stakeholder
interviews, focus groups, and taskforces in parallel with early project
- Conduct corridor level market research early in the project and
- Share information and research among other agencies, especially
those involved along the corridor.
- Recognize the need for employing ITS technology to enhance the
program and for adding to regional ITS capabilities.
5.3.6 Keys to Project Success
- The HOT program must provide viable and recognized travel options
for the public.
- For project acceptance strong stakeholder and public outreach programs
are a necessity.
- When possible it is important to develop a revenue plan that includes
a transit component.
5.4 Minneapolis, MN I-394 Express Lanes
The I-394 Express Lanes, better known as MnPass, became operational in
May 2005 and has nearly two years of operational lessons learned since
5.4.1 Project Objectives
- To improve efficiency of I-394 and to increase person and vehicle
carrying capabilities of the HOV lanes.
- To maintain free flow speeds for transit and carpools.
- To improve highway and transit operations in the corridor with
the revenues generated.
- To use electronic toll collection without toll booths.
- To employ dynamic pricing and in-vehicle electronic enforcement.
5.4.2 Concept of Operations
- Conversion of the existing HOV lanes to HOT lanes with concurrent
travel to be operated 24/7 while operating the two-lane reversible
section for HOT operations EB during the AM Peak and WB for the PM
- Only SOVs are tolled while HOV 2+ and Transit are not tolled (free).
Trucks are not permitted to use the facility.
- For the non-reversible section there is no barrier between the
HOT lanes and adjacent GP lanes. Only double white stripe is used
to delineate HOT-GP separation.
- For the HOV converted segment there are multiple mid-point access
locations to the HOT facility. Access to and from the reversible lane
segment is controlled by three gates that are closed manually prior
to beginning reverse operations.
- Variable dynamic tolling is used during peak travel times with
an average toll rate between $1 and $4, with a maximum of $8.
5.4.3 Innovative Project Features
- The engagement of state leadership early and often throughout the
planning and design phases was instrumental in passing key legislation
and project acceptance.
- A local taskforce, the I-394 Express Lane Community Taskforce,
was created to address issues, desires and design options.
- The program received local and state support by ensuring that 50%
of revenues generated were shared with transit for improvements.
- To maintain support and to encourage continued growth, it is important
to conduct continuing and comprehensive evaluations of the facility
to provide to the public and for use in marketing campaigns.
5.4.4 Major Project Challenges/Mitigation Actions
- Prior to the conversion to HOT lanes there was a high rate of HOV
lane violations, over 20%. To maintain the integrity of the HOT facility
a more effective enforcement presence was needed to detect and to
deter violators. Mobile violation detection equipment was employed
along with contracts with three law enforcements agencies along the
corridor to beef up law enforcement presence. Contracts are with Minnesota
Highway Patrol, Minneapolis Police Department and the Golden Valley
- Opposition from pro-transit constituent groups had to be convinced
that HOT lanes would provide a strong benefit to transit. With the
strong projections provided from the Toll and revenue studies, and
the proposed sharing of the revenue generated, the pro-transit constituent
groups became strong supporters.
- The added SOV traffic on the HOT lanes created unexpected traffic
backups in the downtown area that increase congestion. After opening
of the HOT facility MnDOT constructed an auxiliary lane to provide
additional vehicle storage capacity to mitigate the congestion created
by the added SOV traffic.
5.4.5 Major Lesson Learned
- Have a fiber backbone and communications infrastructure in place
to implement an effective traffic management system.
- The establishment of the I-394 Express Lane Community Task Force
was critical to getting buy-in from the Governor, state legislators,
and community groups. It provided an opportunity for the community
to engage the decision makers early and often through a participatory
- Don’t create new traffic problems and be prepared to add
capacity to address unexpected congestion hot spots.
5.4.6 Keys to Project Success
- Implement an effective enforcement strategy to regulate demand
and to maintain the integrity and effectiveness of the facility.
- Establish a robust public outreach and coordination framework through
which to build political and public support.
- Develop a revenue plan that featured a transit component was critical
in earning the trust and support of the transit community.
5.5 Denver, CO I-25 Express Lanes
The I-25 Express Lane opened in June 2006. Like SANDAG’s I-15 Express
Lanes, I-25 Express Lanes consists of two segments: a 2-mile reversible
segment and a 7-mile barrier-separated HOT lane segment.
5.5.1 Project Objectives
- Improve the efficiency and capacity of I-25 HOV/HOT lanes.
- Expand menu of travel options to the motoring public.
- Use the facility as a showcase congestion management tool.
- Generate sufficient revenue to cover operating expenses.
5.5.2 Concept of Operations
- The reversible section is operational during AM and PM peak periods.
During non-peak periods the section is open outbound only.
- The HOT section (converted HOV) is only operational during the
AM and PM peak periods.
- The entire facility is barrier separated with single entry and
- SOV’s are tolled for use, while HOV2+ and transit travel
without being tolled (free). Trucks over 3-axles using the facility
are charged a premium rate of $18.00 plus the base toll rate which
is per axle based.
- All HOT users, SOV, bus and trucks are required to have transponder.
- A fixed variable toll rate based on time of day dynamic tolling
is used. Toll rates average between $.50 to a maximum of $3.25).
- VES enforcement is automatic using license plate photo and optical
character recognition technology.
5.5.3 Innovative Project Features
- Instead of using LOS, bus travel speed is used as a performance
measure on travel time. If bus speeds or time degrades by 8 min, 45
seconds then the toll rate is raised to push SOVs off of the facility.
The tolls are increased on a pre-determined fixed amount based on
time of day.
- The facility has single ingress and egress points with the northern
section interfacing to two distributor connections and the southern
end feeding directly into downtown.
- The facility has a single tolling point that requires traffic to
divide into lanes for HOVs (free) and non-HOV (tolled) vehicles.
- During off peak hours the reversible lanes are switched using multiple
gates along the facility to restrict access from direct access ramps.
All gate closing is completely automated.
- Customer Service Center is outsourced to existing E-470 Service
5.5.4 Major Project Challenges/Mitigation Actions
- HOV/HOT violations are captured automatically for undetected transponder
reads using V-tolls, or video tolls.
- Vehicle occupancy violations done by visual on-site inspection
by Highway Patrol.
- Automatic vehicle classification system is required for axle classification
needed to capture trucks with more than three axles.
- The reversible lane section in downtown required that travel through
the section be safely and efficiently revered. Gates are used at the
entrance and exit points as well as the direct access ramps to restrict
access. Gate closing is completely automated, is done during off-peak
hours is connected with traffic operations via a verifiable communication
link to verify gate status.
5.5.5 Major Lesson Learned
- Have a political champion to ensure successful project implementation.
- Avoid justifying HOT lanes implementation as a revenue generation
strategy for added capacity. Establish the primary program objective
of HOT lane implementation as a congestion management tool.
- Ensure that managed lane projects are included in MPO plans early.
5.5.6 Keys to Project Success
- Promote future projects as “congestion relief” and
promote early to the public. Don’t promote revenue enhancement;
advocate use as a congestion tool.
- An effective enforcement strategy is a must for a success.
- A strong political champion at both state and local levels is key
to successful project development and implementation.