High Occupancy Vehicle Lanes

High Occupancy Vehicle Lanes Mass Rapid Transit Divyaraj P. Jhala (UTP 0409) 3/12/2010

High Occupancy Vehicle Lanes

Faculty Of Planning And Public Policy, CEPT UNIVERSITY 1

Table Of Contents

CHAPTER 1: INTRODUCTION OF HIGH OCCUPANCY VEHICLE LANES................................ 2 ADVANTAGES OF HOV FACILITIES :............................................................................................................................... 4 QUALIFIED VEHICLES .................................................................................................................................................. 6 TYPES OF HOV FACILITIES .......................................................................................................................................... 7 HOURS OF OPERATION ............................................................................................................................................... 8

CHAPTER 2: HIGH OCCUPANCY LANE CAPACITY................................ ................................ ..... 9 DEFINING HOV LANE CAPACITY .................................................................................................................................. 9 OPTIONS FOR USING AVAILABLE HOV LANE CAPACITY ................................................................................................. 11

CHAPTER 3: EVALUATION OF H.O.V. LANES ................................ ................................ ........... 16 PURPOSE AND SCOPE OF HOV PROJECT EVALUATIONS ................................................................................................. 16 BENEFITS OF CONDUCTING BEFORE -AND-AFTER EVALUATIONS ...................................................................................... 17 APPROACH FOR EVALUATING FREEWAY H.O.V. FACILITIES ............................................................................................. 18 SUGGESTED OBJECTIVES , MEASURES OF EFFECTIVENESS , THRESHOLDS , AND DATA NEEDS ................................................. 19

CHAPTER 4: CASE STUDY: THE EVOLUTION OF THE HOUSTON HOV SYSTEM .............. 28 OVERVIEW OF HOUSTON AREA ................................................................................................................................. 29 METHODOLOGY ADOPTED FOR CASE STUDY ................................................................................................................ 30 EVOLUTION AND USE OF THE HOUSTON HOV LANE SYSTEM ............................................................................ 30 Development and Operation of the HOV Lane System......................................................................................... 30 USE OF THE HOV LANE SYSTEM ................................................................................................................................ 36 ISSUES TO BE CONSIDERED FOR DEVELOPING AND OPERATING MANAGED LANES .............................................................. 40 ONGOING CONSIDERATION OF ENHANCEMENTS ........................................................................................................... 40

REFERENCES: ................................ ................................ ................................ ................................ ... 42



Chapter 1: Introduction of High Occupancy Vehicle Lanes

In the face of growing urban congestion, the range of strategies to maintain and

improve highway service is also increasing. The traditional approach has been the addition of

general-purpose lanes. However, because of the high costs and impacts of creating new

capacity, increasing attention is also being given to strategies that make the maximum use of

existing highway capacity.

These strategies focus on both highway supply and demand. The most basic supply-side

measure is the provision of additional roadway capacity. Given the environmental concerns and

cost of adding new capacity, Departments of Transportation (DOTs) are also making increased

use of Intelligent Transportation Systems (ITS) technologies to support improved operational

efficiency on existing facilities by focusing on operational control and the provision of real time

user information.

At the same time, transportation officials are using a range of demand management

strategies to influence user demand and provide preferential services to certain vehicle types.

One such strategy, High Occupancy Vehicles (HOV) lanes, reserves existing or new highway

lanes for the exclusive use of car pools and transit vehicles. In some areas, DOTs are expanding

HOV lanes into metropolitan area-wide networks. An additional management strategy uses

variable prices on tolled facilities to attract motorists to lower priced off-peak times, thereby

maintaining higher service level volumes during peak periods.

In transportation engineering and transportation planning, a high-occupancy vehicle

lane (also called an HOV lane or carpooling) is a lane reserved for vehicles with a driver and one

or more passengers. These lanes are also known as carpool lanes, commuter lanes, diamond

lanes, express lanes, and transit lanes.

HOV facilities are intended to help maximize the person-carrying capacity of the

roadway. This is done by altering the design and/or the operation of the facility in order to

provide priority treatment for high-occupancy vehicles. The definition of an HOV can include

buses, Vanpools, and Carpools. By encouraging greater use of these modes, HOV projects

increase the number of people, rather than the number of vehicles, being carried on a freeway

or roadway.

A primary concept behind these priority facilities is to provide HOVs with both travel

time savings and more predictable travel times. These two benefits serve as incentives for

individuals to choose a higher-occupancy mode. This, in turn, can increase the person-

movement capacity of the roadway by carrying more people in fewer vehicles. In some areas,

additional incentives, such as reduced parking charges or preferential parking for Carpools and



Vanpools, have been used to further encourage individuals to change their commuting habits.

The success and acceptance of HOV projects can be influenced by these supporting facilities,

services, and programmes. Thus, H.O.V. Facilities often involves variety of elements aimed at

encouraging commuters to use buses, vanpools or carpools. Figure 1

shows buses, Vanpools, and Carpools can accommodate more persons in fewer vehicles than automobiles with only one person.

The intent of H.O.V. facilities is not to force individuals into making changes against their will. Rather the objective is to provide cost effective travel alternative that a significant volume of commuter will find attractive to change from driving alone to using a higher occupancy mode. The HOV lanes and other supportive elements help provide the incentives to encourage this mode change.

H.O.V. Facilities may focus on meeting one or more of three common objectives. Those Objectives are: Increase Average Number of Persons per vehicle: The travel time savings and travel

time reliability offered to high- occupancy vehicles provide incentive for single occupant

automobile driver to change from driving alone to using a bus, carpool or vanpool. Thus, major

objective of H.O.V. project is to move people rather than vehicles. This, in turn increases

average number of people per vehicle on road way or travel corridor.

Preserve the Person-Movement Capacity of the Roadway: Opportunities to expand

the vehicular capacity of freeways are limited in many areas. HOV lanes, when implemented in

appropriate corridors and operated properly, can help ensure future capacity is available to

serve anticipated growth in person travel. An HOV lane, which can move two to five times as

many persons as a general-purpose lane, may effectively double the capacity of the roadway to

move people. In addition, the vehicle occupancy levels required to use an HOV lane can be

raised as needed in response to congestion on the facility. This helps ensure that the HOV lane



continues to offer the high speeds and reliable trip times that are essential to HOV facility

success.

Enhance Bus Transit Operations: HOV lanes offer a number of advantages to transit

operators. Travel times, schedule adherence, and vehicle and labor productivity all can

improve. HOV lanes may offer a safer operating environment for buses. All of these factors help

in attracting new bus riders and in enhancing the operations of the service.

High Occupancy Toll (HOT) lanes: Combines HOV and pricing strategies by

allowing single occupancy vehicles to gain access to HOV lanes by paying a toll. The lanes are

“managed” through pricing to maintain free flow conditions even during the height of rush

hours. The appeal of this concept is tri-fold:

• It expands mobility options in congested urban areas by providing an opportunity for

reliable travel times to users prepared to pay a significant premium for this service;

• It generates a new source of revenue which can be used to pay for transportation

improvements, including enhanced transit service; and

• It improves the efficiency of HOV facilities.

The combined ability of HOT operations to introduce additional traffic to existing HOV

facilities, while using price and other management techniques to control the number of

additional motorists and maintain high service levels, renders the HOT lane concept a promising

means of reducing congestion and improving service on the existing highway system.

ADVANTAGES OF HOV FACILITIES : High-occupancy vehicle facilities have most commonly been used in roadway corridors that are

either at, or near, capacity, and where the physical and/or financial feasibility of expanding the

roadway is limited. When properly planned and implemented, HOV facilities can offer a number

of advantages. Some of the advantages of high-occupancy vehicle projects that should be

considered in the planning process include the following:

Trip Time Reliability: Traffic volumes on H.O.V. lanes are managed to ensure superior,

consistent, and reliable travel times, particularly during peak travel periods.

Travel Time Savings: H.O.V. lanes allow High occupancy vehicles and paying non-HOV motorists

to travel at higher speeds than vehicles on congested general-purpose lanes.



Transit Improvements: HOT lane revenues may be used to support transit improvements, and

new HOT lane facilities provide faster highway trips for transit vehicles.

Enhanced Corridor Mobility: Improved trip time reliability, higher speeds, travel time savings,

and possible transit improvements all lead to greater mobility at the corridor level.

Environmental Advantages: Compared to general-purpose lanes, H.O.V. lanes may provide

environmental advantages by eliminating greenhouse gases caused by stop-and-go traffic, and

by encouraging people to use carpools and mass transit, thereby reducing the number of cars

on the road.

Trip Options: In congested corridors with HOV facilities and transit service, HOT lanes provide

SOV motorists with an additional travel choice: the option of paying for a congestion-free,

dependable and faster trip.

Costs: - While actual implementation costs depend on the type of facility and the site, when

compared to other fixed-guide way transit alternatives or the addition of multiple general-

purpose lanes, HOV priority treatments often represent the low end of the cost scale. This is

especially true when the HOV treatment is developed within existing freeway rights-of-way.

Implementation lime -HOV facilities can be planned and implemented within reasonably short

time periods. While the exact timing depends on the type of facility and site, major HOV lanes

have been planned designed and constructed within a three- to eight-year time period.

Staged implementation: HOV facilities allow for the staging of construction, and can often

be opened for use as the individual segments of the overall project are completed.

Lower Risk - Compared to other fixed transit improvements, HOV facilities may represent a

lower risk option. Should the HOV lane not be sufficiently utilized, it may be converted to other

uses, such as mixed-flow operation or emergency shoulders.

Multi-Agency Funding: HOV facilities are often eligible for funding from a variety of sources.

Federal highway and transit funds can be used for HOV projects, and state and local

transportation funds have often been used.

Multiple User Groups: Most HOV facilities are used by not only transit vehicles but also by

Carpools and Vanpools. Thus, multiple user groups have access to the facility, providing a wider

base of support. Also, Carpools are served at low marginal costs and can offer an effective



means of serving suburban travel patterns that are sometimes difficult to serve with

conventional transit.

Operating Speeds: Bus services on HOV lanes are usually express or limited-express. As a

result, the line-haul speeds are usually high, with many operating at or above 50 miles per

hour.

Flexibility: Buses, Carpools, and Vanpools can use the existing street system for the collection

and distribution portions of the trip. This can provide a good deal of flexibility in service

orientation, especially in matching service needs to changing demands. Park-and-ride lots and

other support facilities need not always be located directly adjacent to the HOV lane, allowing

for the ability to utilize less expensive land remote from the facility.

Time Adjustable Operation: Some priority facilities operate only in the peak periods and are

used for other purposes at other times. In addition, the occupancy requirements on the facility

may be different during different times of the day. This provides for the ability to increase the

person carrying capacity of the facility in the future without needing to expand the vehicular

capacity.

QUALIFIED VEHICLES Qualification for HOV status varies by locality, and may require more than two people.

Qualification for HOV status varies by locality, and may require more than two people. When an

automobile is used as an HOV, the group of people using it is often called a carpool, though the

term HOV includes buses and vans. However, bus lanes may not necessarily be intended for use

by carpools. An HOV or carpool may be allowed to travel on special road lanes, on which

vehicles not meeting minimum occupancy are prohibited, called restricted lanes, carpool lanes

or diamond lanes. In some cases, single occupant vehicles are allowed provided that they are

hybrid vehicles or use native fuels.

In some regions, buses are allowed to travel on the road shoulder when traffic becomes

heavy, but it is often still illegal for cars (even HOVs) to take the shoulder to get around traffic

jams. HOV facilities are open to buses, Vanpools, and Carpools. Most facilities also allow use by

taxis meeting the occupancy requirements, and allow police and emergency vehicles to use the

lanes without meeting the occupancy requirements. The carpool occupancy requirements for

existing HOV facilities vary between 2+ and 3 + persons per vehicle. No facilities currently use a

4+ requirement. Some HOV facilities may adapt various occupancy requirements, like in



morning and evening peak hour it is 3+ while in other cases it is 2+. The Katy Transit way in

Houston is the only HOV facility with variable occupancy requirements. A 2+ requirement is

utilized during all operating periods except during the morning and afternoon peak hours, when

a 3+ requirement is in effect.

TYPES OF HOV FACILITIES High-occupancy vehicle facilities on freeways or separate rights-of-way are generally

classified into the following categories.

• Exclusive HOV Facility, Separate Right-of-Way- This type of HOV facility is a

roadway or lane(s) developed in a separate right-of-way and designated for the

exclusive use by high-occupancy vehicles. Most existing facilities of this type are

designed for, and utilized by, buses only. Most are two-lane, two-direction facilities.

Examples of this type of HOV treatment are the South and East Bus ways in Pittsburgh

and the transit way system in Ottawa, Ontario Canada.

• Exclusive HOV Facility, Freeway Right-of-Way- This type of HOV facility is a lane(s)

constructed within the freeway right-of-way that is physically separated from the

general purpose freeway lanes and used exclusively by HOVs for all, or a portion of, the

day. Most exclusive HOV facilities are physically separated from the general purpose

freeway lanes through the use of concrete barriers. However, a few exclusive facilities

are separated from the general purpose lanes by a wide painted buffer. Exclusive HOV

facilities in freeway rights-of-way are usually open to all types of HOVs-buses, Vanpools,

and Carpools. Examples of exclusive barrier-separated HOV facilities include the

Houston HOV lanes and the Shirley Highway HOV lanes in the Washington,

D.C./Northern Virginia area.

• Concurrent Flow Lane- Concurrent flow HOV lanes are defined as a freeway lane in

the same direction of travel, not physically separated from the general-purpose traffic

lanes, designated for the exclusive use by HOVs for all or a portion of the day.

Concurrent flow lanes are usually, although not always, located on the inside lane or

shoulder. Paint striping is a common means used to delineate these lanes. HOV facilities

of this type are usually open to buses, Vanpools, and Carpools. Examples of concurrent

flow lanes are SR 520, l-5, and I-405 in Seattle, Route 55 in Orange County, California,

and Route 101 in San Jose, California.



• Contra flow Lane - This type of HOV facility is a freeway lane in the off-peak direction

of travel, typically the innermost lane, designated for exclusive use by HOVs traveling in

the peak direction. The lane is separated from the off-peak direction general-purpose

travel lanes by some type of changeable treatment, such as plastic posts or pylons that

can be inserted into holes drilled in the pavement. Contra flow lanes are usually

operated during the peak periods only, and some operate only during the morning peak

period and then revert back to normal use in non-peak periods. Several examples of this

type of facility are located in the New York City area. In the Dallas area, the East R.L.

Thornton (l-30 East) contra flow lane represents the first application of the moveable

concrete barrier technology with an HOV facility.

• Reversible lanes- Some cities that use separated HOV lanes make them reversible; i.e.

usable only by inbound traffic during the morning rush and usable only by outbound

traffic during the evening rush. Houston is a city which employs reversible HOV lanes.

• Queue jumping- Some cities use HOV lanes to allow carpool traffic to bypass areas of

regular congestion. For example, in Metro Vancouver, British Columbia, HOV traffic is

separated from general traffic and given priority access to the entrance to George

Massey Tunnel.

HOURS OF OPERATION The operating hours of HOV facilities can be characterized by three different scenarios:

24-hour operation; morning and afternoon/evening operation; and peak-period only operation.

No one specific operating scenario necessarily equates to a certain type of facility. Operating

hours for the exclusive and concurrent flow lanes vary. The exact time these facilities operate

with HOV restriction varies. Most operate from approximately 6 a.m. to 9 a.m. in the morning

and 3 p.m. to 6 or 7 p.m. in the evening.



Chapter 2: High Occupancy Lane Capacity

DEFINING HOV LANE CAPACITY As discussed previously, the goal of an HOV facility is to provide travel time savings and

trip travel time reliability to buses, vanpools, and carpools, to encourage individuals to change

from driving alone. Vehicle eligibility requirements and vehicle-occupancy requirements are

typically established at levels that encourage use of the facility and the formation of new

carpools, but that will not create demand high enough to make the lane congested. The

challenge to operating agencies is to maintain traffic flow levels that provide the travel time

savings and the trip time reliability bus riders, vanpoolers, and carpoolers come to expect.

Different agencies responsible for operating HOV facilities use different measures and

techniques to help monitor the operation of HOV facilities and to determine when an HOV lane

is becoming too congested. There are two typical measures used; 1) vehicles per hour per lane

(vphpl) and 2) average speeds.

The National Cooperative Highway Research Program HOV Systems Manual identified

that volumes of 1,200 to 1,500 vphpl on most types of HOV facilities will begin to experience

degradations in travel time savings and travel time reliability. The manual notes that the

maximum flow or capacity will vary by facility. Some HOV lanes serving primarily carpools are

operating successfully with up to 1,700 or 1,800 vphpl during the peak hour. Others, like the

bus-only contraflow lane approaching the Lincoln Tunnel, reach capacity at 700 to 800 vphpl.

Caltrans uses 1,650 vphpl as the maximum threshold for freeway concurrent flow facilities.

General maximum operating thresholds for different types of HOV facilities (As per HOV

Systems Manual),

•Separate right of way, bus-only – 800–1,000 vphpl

• Separate right of way, HOV – 1,500–1,800 vphpl

• Freeway, exclusive two-directional – 1,200–1,500 vphpl

• Freeway, exclusive reversible –1,500–1,800

• Freeway, concurrent flow – 1,200–1,500 vphpl

• Freeway contraflow, bus-only – 600–800 vphpl

• Freeway contraflow, HOV – 1,200–1,500 vphpl

• HOV bypass lanes – 300–500 vphpl



The updated American Association of State Highway and Transportation Officials

(AASHTO) Guide for High-Occupancy Vehicle Facilities (7) reflects similar maximum ranges, with

two exceptions. The high end of the maximum ranges for freeway, exclusive reversible lanes

and freeway concurrent flow lanes are identified as 1,600 vphpl.

A second approach to identify capacity problems is to monitor travel speeds in an HOV

lane and travel-time reliability. The Washington State Department of Transportation (WSDOT)

uses a guide that HOV lane vehicles should maintain or exceed an average speed of 45 mph or

greater at least 90 percent of the time they use the lane during the peak hours, measured for a

consecutive six-month period.

FHWA uses congestion measures focusing on the average duration of congested travel,

the travel time index, and the buffer index. There are two measures addressing the average

duration of congested travel. The first is that for any five-minute interval a trip is congested if

its duration exceeds 130 percent of free-flow or un-congested duration. The second measure is

that if more than 20 percent of all trips in the network are congested in any five-minute time

interval, the entire network is congested for that time interval.

The travel time index is defined as the ratio of congested and un-congested travel times

averaged over all congested trips. The buffer index is defined as the ratio of total travel budget

required for 95 percent on-time reliability over the un-congested travel time averaged over all

congested trips. The buffer index provides a measure of not only how congested the system is,

but also how reliable the system is. It provides a performance measure from the customer’s

perspective. The buffer index represents the amount of time commuters need to build into

their trip to arrive at their destination on time 95 percent of the time.

It is important to note that numerous factors may influence the capacity of an HOV lane.

Factors which may influence the capacity of an HOV lane include the type of HOV facility, the

design, the number and the design of access points, the terminus design, traffic volumes in the

general-purpose lanes, design and access elements of the general-purpose lanes, local

conditions and perceptions, and the goals and objectives of a project. Information on how

these factors may influence the capacity of an HOV lane is summarized next.

•Type of HOV Facility – As noted previously, the capacity varies by type of HOV lane. Bus-only

lanes and contraflow HOV lanes typically have lower capacities than concurrent flow and

exclusive HOV lanes due to their purpose and their design.

• Design Considerations – An HOV facility with geometric constraints or sections with less than

standard designs typically have lower capacity or maximum operating thresholds than those

with standard designs.

• The Number and the Design of Access Treatments – The number of access points and the

design treatments will influence the capacity of an HOV lane. HOV lanes with direct access



treatments, such as flyover ramps, typically have higher capacity than HOV lanes with access

directly into and out of the adjacent freeway lane. In addition, providing continuous access

tends to lower capacity as HOVs may merge into and out of the lane at any point.

• Terminus Design – The terminus of an HOV lane influences capacity of an HOV lane. Capacity

will be lower if the design requires HOVs to merge back into an adjacent freeway lane.

Providing direct access to frontage roads and park-and-ride lots typically increases capacity.

• Traffic Volumes in the General-Purpose Lanes and Level of Congestion in the Corridor – The

maximum operating threshold or capacity may be higher in a heavily-congested corridor than in

one with lower levels of congestion. However, high levels of congestion in the general-purpose

lanes may reduce the capacity of an HOV lane if it causes problems for HOVs entering and

exiting the lane.

•Local Conditions and Perceptions – The perception of HOV lane users about travel time

savings and trip time reliability, and the perception of commuters and the public about HOV

lane utilization may influence the desirable maximum operating thresholds of an HOV lane.

Unique local conditions may also influence the operating capacity of an HOV facility.

• Goals and Objectives of Project – The goals and objectives of a project may influence the

capacity and the maximum operating thresholds. For example, a project intended to give buses

priority around a congested freeway segment could be expected to have a lower threshold than

an exclusive HOV lane.

OPTIONS FOR USING AVAILABLE HOV LANE CAPACITY A number of options may be appropriate for consideration by operating agencies if there is

available capacity in an HOV lane. These options include allowing other categories of HOVs and

lowering the vehicle-occupancy requirements. Other possible alternatives include using pricing

to permit lower-occupant or single-occupant vehicles to use the lanes. Still other alternatives

include allowing environmentally friendly vehicles and special user group vehicles to use the

HOV lanes. Law enforcement, emergency services, public service, and public transportation

vehicles not meeting the occupancy requirements are examples of possible special user groups.

Allowing trucks and commercial vehicles to use an HOV lane is another alternative, although

design and safety issues typically limit consideration of these types of vehicles.

These potential options are briefly described in this section.

Allowing Other Categories of HOVs: A first approach to consider if there is available

capacity in an HOV lane is allowing additional types of HOVs that may currently be excluded. If

carpools and/or vanpools are not currently allowed to use an HOV facility that has available



capacity, these two classes of HOVs would be logical to consider first. Potential issues with this

approach include design or operational issues that limit use by carpools and vanpools, and the

potential that demand will exceed the available capacity. Advantages of this approach include

maintaining the HOV goals and objectives of a project, encouraging mode change, and

supporting air quality improvement efforts. Lowering Vehicle-Occupancy Requirements: A second approach for addressing

available capacity is to lower the vehicle-occupancy requirement. The application of this

approach is limited, as most HOV lanes currently use a 2+ designation. The few HOV facilities

that use a 3+ designation do so primarily because the facility would be too congested at the 2+

level. The San Bernardino Freeway busway provides the best recent example of the possible

consequences of lowering the vehicle-occupancy requirement from 3+ to 2+, as required by state

legislation. The change, which was implemented in January 2000, resulted in the HOV lane

becoming too congested. Peak-hour travel speeds on the busway were reduced from 65 mph to 20

mph, while peak hour travel times increased by 20 to 30 minutes, and bus on-time performance

declined significantly. While peak-hour vehicle volumes in the HOV lane increased from 1,100 to

1,600, the number of persons carried declined from 5,900 to 5,200. At the same time, no significant

improvements were realized in the general-purpose freeway lanes.

As demonstrated by the El Monte Busway example, the main potential issue with

lowering the vehicle-occupancy requirement is that an HOV lane will become too congested. In

addition to degrading the travel time savings and trip time reliability HOV lane users have come

to expect, this approach may cause 3+ carpools to disband and/or influence bus riders to

change to 2+ carpools. The application of this option is also limited in that the majority of HOV

lanes already use a 2+ requirement. Tolled or Priced Vehicles: Another possible approach is to allow lower or single-

occupancy vehicles to use an HOV facility for a fee. This technique is commonly referred to as

value pricing or HOT lanes. Value pricing is currently in use on the I-15 HOV lanes in San Diego

and the Katy and the Northwest HOV lanes in Houston. The I-15 project allows single-occupancy

vehicles to use the HOV lanes, while the two projects in Houston allow two-person carpools to

use the HOV lanes during the 3+ restricted periods for a fee. The toll lanes on SR 91 in Orange

County, California provide a reduced toll charge to 3+ carpools. Other toll facilities around the

county provide carpools with lower toll fees. Value pricing projects are being considered and

implemented on HOV lanes in Minneapolis, Denver, Seattle, and other areas.

Potential advantages of this technique include maximizing use of available capacity,

managing demand, expanding the eligible user groups, addressing real or perceived low use



levels, and generating new revenues. Possible issues include enforcement, initial costs of

installing and operating the toll collection facilities, adding too many vehicles to the lane, and

equity issues. Environmentally Friendly Vehicles: Another option to address available HOV

capacity is allowing environmentally friendly vehicles to use the lane without meeting the

occupancy requirements. Some States have authorized ILEV use of HOV lanes without meeting

minimum occupancy requirements. ILEVs were defined through EPA rulemaking in 1993 as

vehicles meeting specific low-emission vehicle exhaust emission standards and also having low

levels of evaporative emissions. The definition was intended to limit ILEVs to vehicles that

operate on a single dedicated non-gasoline fuel, such as electricity, compressed natural gas

(CNG), and liquefied natural gas (LNG). Hybrid vehicles, which operate using a combination of

gasoline and electricity, do not qualify as ILEVs.

Possible issues associated with providing HOV exemptions for environmentally friendly

vehicles include demand exceeding the capacity of the lane, enforcement, public perceptions,

and potential equity issues. Potential advantages of this approach include adding new user

groups, encouraging the purchase and use of these types of vehicles, and improving air quality. Law Enforcement and Emergency Vehicles: Most state and local policies allow

marked (rooftop emergency lights and sirens) law enforcement and emergency vehicles to use

HOV lanes without meeting the occupancy requirements. Police, fire, and other enforcement

and emergency vehicles are typically included in this category of exempt vehicles.

Issues may arise, however, when the definition of allowable vehicles is too vague or the

proper definition is not enforced and law enforcement and emergency personnel traveling

alone in their personal vehicles or in unmarked agency vehicles when not on duty use the HOV

lanes on a regular basis. This misuse may result in overloading the lane, public perception that

the vehicle-occupancy requirements are not being enforced, and the need for more

enforcement.

Designated Public Transportation Vehicles: Buses carrying passengers are an important part of most HOV systems. Allowing designated public transportation vehicles to use HOV lanes when they do not meet the occupancy requirement may be one approach to using available capacity.

Providing access to these vehicles is not an issue in most areas since the total number of buses is relatively small and the potential to use HOV lanes in the off-peak direction of travel is limited in many cases. Potential benefits of this approach include cost savings and enhanced operating effectiveness for transit systems and improved service for riders. These benefits may



result in increased transit ridership. Issues may arise however, if private transportation vehicles, such as taxicabs, airport shuttles, and similar vehicles are provided with occupancy exemptions.

Allowing Truck and Commercial Vehicle Access. The potential use of HOV lanes by trucks

during all operating hours or just the off-peak periods has been suggested in a few facilities.

Potential issues to examine in considering truck use of an HOV facility include the type of HOV

facility, access, design limitations, safety concerns, and the potential benefits to commercial

vehicle operators. HOV lanes and access facilities may not be designed to accommodate

commercial vehicles and there may be geometric limitations that prohibit trucks from using a

facility. Safety concerns may include trucks veering across general-purpose lanes to access an

HOV lane and conflicts between HOVs and trucks. Finally, truck use may increase the costs

associated with operating an HOV facility if additional personnel are needed to monitor a

facility or if operating hours are extended. Truck use of HOV lanes may also cause pavements to

deteriorate faster.

Table 1. Potential Issues and Advantages Associated with Options for Using Available HOV Lane Capacity.

Option Potential Issues/ Limitations

Potential Advantages

Allow other HOVs, such as carpools in a bus- and vanpool-only lane

• Design limitations. • Operational limitations. • Demand may exceed capacity and overload the lane.

•Maintains HOV goals/objectives. •Supports air quality efforts. •Encourages mode change.

Lower Occupancy Requirement •Demand may exceed capacity and overload the lane. • Operational limitations. • Few applications, as most HOV projects use 2+ requirement.

•Maintains HOV goals/objectives. •Supports air quality efforts.

Tolled/Priced Vehicles •Design and cost associated with tolling infrastructure and operation. •Demand may exceed

• May generate significant revenues. • May build support for HOV lanes among additional user groups.



capacity. •May not support HOV goals/objectives. • Equity concerns. • Enforcement.

Environmentally Friendly Vehicles •Demand may exceed

capacity and overload the

lane.

• Public perception.

• Enforcement.

•May not support HOV

goals/objectives.

•Possible equity concerns.

•May encourage purchase

of environmentally friendly

vehicles.

•May help improve air

quality.

Law Enforcement Vehicles (Law

enforcement, Fire, EMS)

• Defining allowed vehicles.

•Does not support HOV

goals/objectives.


• Enforcement.

• May enhance response to

emergencies.

Designated Public Transportation Vehicles • Defining allowed vehicles.


• May be few opportunities

due to transit

orientation/operation.

•Additional benefits and

cost savings for transit

operators.

• Service enhancements for

riders.

• May increase ridership.

Trucks and Commercial Vehicles •Does not support HOV

goals/objectives.

• Design limitations.

•Additional cost to operate.

• Crash/safety concerns.

• May help separate trucks

from other traffic, which

may provide safety

benefits.



Chapter 3: Evaluation Of H.O.V. Lanes

PURPOSE AND SCOPE OF HOV PROJECT EVALUATIONS Evaluations of transportation projects provide an opportunity to compare alternatives,

measure the worth or value of a project, and determine if the goals of a project have been met.

Evaluations are usually conducted at different stages in the project development and

implementation process. Initially, competing alternatives are examined and evaluated to assist

with the selection of the preferred approach. Once the decision has been made on a specific

course of action, before-and-after evaluations are conducted to determine if the anticipated

benefits have in fact been realized and to assist in identifying ways to improve similar projects

in the future. Further, ongoing monitoring and periodic evaluations are often undertaken to

ensure that the project continues to meet the desired goals and to identify possible areas for

improvement.

Evaluations of HOV facilities are often conducted for similar purposes. First, an HOV

facility may be one of many alternatives considered in the planning stage of a project. Second,

once selected as the preferred alternative and implemented, evaluations may be conducted

after an initial demonstration or start-up phase. Evaluations at this point focus on identifying if

the benefits estimated for the facility are being realized. Finally, ongoing monitoring and

periodic evaluations may be conducted on the HOV facility to ensure that these benefits

continue to be realized and to improve the operation of the lane. To date, ongoing evaluations

of HOV projects have been limited. Thus, HOV facilities can be evaluated as one of many

alternatives during the planning stage, shortly after implementation, and on an ongoing basis.

This procedure is primarily concerned with a comparison of conditions before the HOV

project is constructed and those after implementation, and the ongoing monitoring of the

facility. However, it is important to note that much of the information generated during the

analysis of alternatives may also be used in the before-and-after evaluation. The results of this

analysis, which often include the use of simulation models or other forecasting techniques, may

form the basis for comparison with the actual operation of the facility. In addition, other

measures, such as the UMTA cost-effectiveness index, may be used in evaluating alternatives.

Thus, a link exists between the different stages of evaluations.



BENEFITS OF CONDUCTING BEFORE-AND-AFTER EVALUATIONS Multiple benefits can be realized from conducting before-and-after studies of HOV

projects. Evaluations provide the ability to determine if the goals and objectives of the project

have been achieved. In addition, the information obtained from the evaluation process has

numerous secondary benefits. This section provides a brief summary of the reasons for

conducting HOV project evaluations and the benefits resulting from these efforts.

A main reason for conducting before-and-after evaluations of HOV projects is to identify

the benefits accrued from the project and to determine how well the goals and objectives

identified for the facility are being met. Evaluations provide an opportunity to ascertain the

degree to which the desired results are in fact occurring. Further, before-and-after studies

provide an official data base for the project. This can help ensure that all groups are utilizing the

same data and can help to clarify any possible disagreements over the impact of the project.

The results of before-and-after studies are also important in future planning efforts

within the metropolitan area. The information generated can be used to calibrate planning and

simulation models for future use and can be used to assist in the decision making process in

other corridors. Planning and simulation models are often used in the analysis of alternatives.

Utilizing the results from the before-and-after studies to modify these to more accurately

reflect actual experience provides a valuable check on the modeling process and improves the

future capabilities of the models. In addition, the results from the evaluation and the

experience gained from the project can enhance the decision making process on future

projects.

The information collected as part of the evaluation process has value for operating

decisions relating to the HOV facility. Information on usage, violation rates, and accidents are

all critical for ensuring the efficient and safe operation of the facility. Monitoring these and

other aspects of the HOV lane as part of the evaluation process can identify problems that may

need to be addressed. For example, changes in operating hours, vehicle occupancy

requirements, bus service levels, and access/egress points may be necessary. Thus, the data

provided from before- and-after studies, especially longitudinal data on the use of the facility,

serves a critical operations function. This information can also be used to evaluate the

marketing and public information programs associated with the facility and identify if additional

marketing is needed.

Evaluations may also be needed to meet federal or state requirements. A variety of

funding sources have been used to implement HOV projects. Different funding sources and

programs may require before-and-after evaluations. Even when not a requirement, evaluations

of HOV projects can serve a useful purpose to assist in justifying future funding for similar

facilities.



Lastly, by providing information on different projects throughout the country, the

results of evaluation studies can assist in establishing an ongoing national data base on HOV

facilities. Building a common body of knowledge on the use and effectiveness of HOV facilities

is needed to continue to keep pace with the issues facing transportation professionals and

decision makers in urban areas. A common national data base on HOV facilities can assist in

ensuring that all areas are kept informed of the latest developments in the field.

Following the suggested approach and procedures outlined in this chapter will provide

for a comprehensive before-and-after and ongoing evaluation program for freeway HOV

facilities. The listing of objectives, measures of effectiveness, threshold ranges, and data needs

should provide adequate direction for the development of an evaluation program that meets

the needs and resources of individual areas, while helping to provide comparability among

different projects. In order to provide further assistance in the development of a

comprehensive evaluation program, the next chapter presents an extensive discussion of data

collection methodologies and techniques.

APPROACH FOR EVALUATING FREEWAY H.O.V. FACILITIES The suggested procedures, as outlined in this chapter, build on the strengths of these

studies. The approach and procedures are presented to provide guidance to agencies

developing before-and- after evaluation programs for HOV facilities. It is realized that individual

evaluation programs need to be tailored to the scope of the specific project, special issues of

concern, and staff and financial resources available in each area. The suggested approach

provides the flexibility to address local concerns and available resources while at the same time

providing a comprehensive and more standardized process. The utilization of a more uniform

approach should enhance both the quality and comparability of evaluations of HOV facilities

throughout the country.

While limitations on staff and financial resources are concerns in most areas,

undertaking before-and-after evaluations of HOV facilities should not be taken lightly. A lack of

commitment and allocation of adequate resources can negate the value of the resulting

study. An insufficient evaluation may be worse than no evaluation at all, as it may lead to

erroneous conclusions and inappropriate decisions. The general approach suggested in this

chapter provides a framework for conducting before-and-after evaluations. However, in

actual practice, the quality of these evaluations will be closely correlated to the time and

resources committed to the study.



SUGGESTED OBJECTIVES , MEASUR ES OF EFFECTIVENESS , THRESHOLDS , AND

DATA NEEDS A variety of objectives, both quantitative and qualitative, have been used to evaluate

HOV facilities. The first step in developing an evaluation program is to clearly define the project

objectives. The following general objectives represent some of those most commonly

associated with HOV facilities.

• The HOV facility should improve the capability of a congested freeway corridor to move more

people by increasing the number of persons per vehicle.

• The HOV facility should increase the operating efficiency of bus service in the freeway

corridor.

• The HOV facility should provide travel time savings and a more reliable trip time to high-

occupancy vehicles utilizing the facility.

• The HOV facility should provide favorable impacts on air quality and energy consumption.

• The HOV facility should not unduly impact the operation of the freeway general-purpose main

lanes.

• The HOV facility should increase the per lane efficiency of the total freeway facility.

• The HOV facility should be safe and should not unduly impact the safety of the freeway

general-purpose mainlanes.

• The HOV facility should have public support.

• The HOV facility should be a cost-effective transportation improvement.

These statements represent general objectives that reflect the reasons most commonly

cited for developing HOV facilities. These objectives should be defined in more detail and

expanded as necessary so that each represents a measurable statement appropriate to the

specific HOV project. Once the objectives have been clearly defined, the next step is to identify

the appropriate measures of effectiveness (MOEs) that correspond to each objective. These

measures should focus on the key elements of the objectives, so that the information needed

to determine if the objective has been achieved can be obtained.



Commonly used measures of effectiveness associated with each of the objectives were

examined to identify those that appear to represent key elements to be measured. The MOEs

that can assist in determining the impact of the HOV facility are included in the following listing.

Each of the general objectives is presented, along with possible corresponding measures of

effectiveness, threshold guidelines, and data needs. The threshold ranges presented are

intended to serve as very general guidelines. It is realized that the appropriate thresholds will

vary for individual projects depending on local conditions. These elements are summarized in

Tables 7 provided at the end.

Objective: The HOV facility should improve the capability of a congested freeway corridor to

move more people by increasing the number of persons per vehicle.

Measures of Effectiveness: In general, the increase in the peak-hour, peak-direction person

volume resulting from the HOV facility should at least be greater than the percentage increase

in directional lanes added to the roadway. In effect this will be accomplished by increasing the

average vehicle occupancy (persons per vehicle) on the roadway. A significant portion of the

increase in average vehicle occupancy should be the result of creating new carpoolers and new

bus riders, rather than just diverting buses, carpools, and vanpools from the adjacent freeway

lanes or parallel routes to the HOV facility. The attraction of a significant volume of new bus

and carpool users is critical to the effectiveness of HOV facilities. Simply moving existing

rideshare patrons from the general-purpose lanes or parallel routes will not impact the person-

movement capability of the total corridor.

Specific MOEs that may be appropriate for use with this objective include the following:

• Actual and percent increase in the person-movement efficiency on the total freeway facility

(general-purpose lanes plus HOV facility).

• Actual and percent increase in the average vehicle occupancy rate for the total freeway

facility (general-purpose lanes plus HOV facility).

• Actual and percent increase in carpools and vanpools for the total freeway facility (general-

purpose lanes plus HOV facility).

• Actual and percent increase in bus riders for the total freeway facility (general- purpose lanes

plus HOV facility).



For each of these MOEs, it may be appropriate to identify a specific criterion for the

anticipated change in the peak-hour, peak-period, and the daily total (e.g. the actual and

percent increase in bus riders during the peak-hour, peak-period, and daily total).

General Threshold Ranges: Based on experienced, possible threshold ranges for these

MOEs could include at least a 10% increase in the peak-hour, peak-direction average vehicle

occupancy, an increase in person volumes greater than the increase in directional lanes added

to the roadway due to HOV lane implementation, at least a 20% increase in carpoolers, and,

depending on the amount of new transit service provided, a 10% to 20% increase in bus riders.

Data Needs: Primary data needs include before-and-after vehicle and vehicle occupancy

counts on the HOV lane(s), adjacent freeway, and control freeway. Secondary data needs

include before-and-after vehicle and occupancy counts on parallel roadways, and surveys of

users of the HOV facility (bus riders, carpoolers, and vanpoolers) and non-users (individuals in

the general-purpose lanes).

Objective: The HOV facility should increase the operating efficiency of bus service in the

freeway corridor.

Measure of Effectiveness: By increasing bus operating speeds and improving service reliability,

HOV facilities can increase the vehicle operating efficiency of bus service in the freeway

corridor. The following measures of effectiveness can be used with this objective.

• Improvement in vehicle productivity, measured by operating cost per vehicle-mile, operating

cost per passenger, operating cost per passenger mile

• Improved bus schedule adherence, measured by on-time performance

• Improved bus safety, measured by a reduction in vehicle accident rates

General Threshold Ranges: Little analysis has been done on the impact HOV facilities have had

on bus service productivity, schedule adherence, and safety. Very limited information is

available from the Shirley Highway HOV lanes, San Bernardino Busway, and Houston HOV lanes.

Experience from these areas indicate that improvements of 5% to 20% in vehicle productivity

can be realized with the implementation of HOV facilities, resulting in similar reductions in

operating cost per vehicle-mile, operating cost per passenger, and operating cost per passenger

mile. On-time schedule adherence can be expected to improve significantly. Experience from a

number of areas indicates that the average schedule adherence for buses operating on HOV

lanes improves to 95% or better. The state-of-the-art review did not identify any information on



bus accidents. However, depending on the design of the facility, a reduction in the bus accident

rate could be anticipated.

Data Needs: Data needed for these measures of effectiveness include before-and-after bus

service levels, vehicle productivity, on-time performance, number and severity of bus accidents,

vehicle operating costs, and changes in labor, fuel, and other costs. On-time performance is

usually measured by the number of vehicles arriving at their destination at the scheduled time.

On-time performance may be defined differently by different transit systems, but a range from

arriving on schedule to 5 minutes behind schedule is often used. It is suggested that the actual

arrival times of buses be monitored before-and-after implementation of the HOV facility, as this

provides the most accurate picture of changes in on-time performance. In addition, the

perception of bus users to changes in bus on-time performance can be measured through the

use of on-board ridership surveys.

Objective: The HOV facility should provide travel time savings and a more reliable trip time to

high-occupancy vehicles utilizing the HOV facility.

Measure of Effectiveness: During the peak-periods, the travel time on the HOV facility should

be less than the travel time on the adjacent freeway lanes in the peak-direction of travel. The

reliability of the travel time in the HOV lane should also improve from that experienced in the

general-purpose lanes in the pre-HOV lane period.

General Threshold Ranges: A general guide that has been used in some areas is that the travel

time savings for users of the HOV facility should be approximately one minute per mile for the

length of the HOV facility. This guideline further suggests that a minimum total travel time

savings of at least 5 to 7 minutes should be realized during the peak-hour. The travel time

reliability of vehicles using the HOV facility should improve from the pre-HOV conditions. Both

the Shirley Highway HOV lanes and the Houston HOV lanes have shown significant

improvements in travel time reliability.

Data Needs: Travel time runs of vehicles in the general-purpose lanes should be conducted

before the HOV project is implemented. Travel time runs of vehicles in both the HOV lane(s)

and the general-purpose freeway lanes should be conducted on an on-going basis after the

HOV facility is open. The travel time runs can also be used to measure the travel time reliability.

Objective: The HOV facility should have favorable impacts on air quality and energy

consumption.

Measures of Effectiveness: For the total demand being served by the facility, the HOV lane(s)

should have more favorable impacts on air quality and energy consumption than would either

no improvement at all or the addition of a general purpose lane. The measures most commonly



used with this objective are based on calculations or simulation models that use information

generated from other objectives. The following MOEs are commonly used with this objective.

• Reductions in emissions

• Reductions in total fuel consumption

• Reduction in the growth of vehicle miles of travel (VMT) and vehicle hours of travel

General Threshold Ranges: The HOV lane(s) should have a more positive impact on air quality

and energy consumption than would either no improvement or the addition of a mixed traffic

lane. More specific levels can be set for individual projects based on the results of the demand

estimation process.

Data Needs: Estimations based on vehicle and occupancy counts, travel time runs, and

responses to surveys are used to measure changes in these MOEs. Most simulation models

require a good deal of data. Direct monitoring of air quality impacts along the corridor may be

appropriate in some cases.

Objective: The HOV facility should increase the per lane efficiency of the total freeway facility.

Measures of Effectiveness This objective can be measured by a comparison of the peak- hour

per lane efficiency of the freeway lanes prior to implementation of the HOV project and

combined peak-hour per lane efficiency of the freeway lanes and HOV facility after

implementation. The "before" measure can be calculated by taking the person volume on the

freeway multiplied by the average freeway operating speed. The "after" measure can be

calculated by taking person volume on the freeway multiplied by the average freeway

operating speed combined with the person volume on the HOV facility and multiplied by the

average HOV lane operating speed.

General Threshold Ranges: A 5 % - 20 % increase in the peak-hour per lane efficiency of the

total facility could be expected from an HOV project.

Data Needs: The information obtained from the freeway and HOV lane(s) vehicle and

occupancy counts and travel time runs taken before-and-after implementation of the HOV

facility are used to calculate the per lane efficiency.

Objective: The HOV facility should not unduly impact the operation of the freeway main lanes.

Measures of Effectiveness: The capacity and operating speeds of the adjacent freeway main

lanes should not be degraded due to the implementation of the HOV facility. This can be

measured by a comparison of the level-of-service on the freeway main lanes before-and-after



implementation of the HOV project. As presented next, it is suggested that safety be addressed

in a separate objective.

Threshold Ranges: The level-of-service in the main lanes should not decline due to the

implementation of the HOV project.

Data Needs: The information obtained from the freeway and HOV lane(s) vehicle and

occupancy counts and travel time runs taken before-and-after implementation of the HOV

facility are used to calculate the level-of-service.

Objective: The HOV facility should be safe and should not unduly impact the safety of the

freeway general-purpose main lanes.

Measures of Effectiveness: Appropriate MOEs include a before-and-after comparison of the

following items.

• Number and severity of accidents for HOV and freeway lanes

• Accident rate per million vehicle-miles or million passenger-miles of travel for HOV and

freeway lanes

General Threshold Ranges: It is suggested that the accidents rates should not increase with the

implementation of the HOV facility and that the accident rates should be lower on the HOV

facility than the freeway general-purpose lanes. However, if implementation of the HOV facility

has resulted in the narrowing of the general-purpose lanes or shoulder, or the removal of a

shoulder, this may not be a realistic threshold. Thus, it is suggested that this MOE and possible

threshold ranges be carefully examined for each project. Given the experience with some of the

evaluations of HOV facilities in California, it appears important to monitor not only the freeway

lanes and HOV facility, but also a control freeway to determine any overall changes in accident

rates in the area. Maintaining the same analysis procedure throughout the evaluation is

another lesson from the California experience.

Data Needs: Statistics on the accident rates on the freeway main lanes should be collected for a

representative period of time before the HOV facility is opened. Statistics on the accident rates

for both the HOV lane(s) and the freeway main lanes should then be collected for a

representative period of time after the HOV facility is open. Information collected should

include the number, type, and severity of the accidents. Continued, ongoing monitoring should

also be conducted.

Objective: The HOV facility should have public support.

Measures of Effectiveness: Opinion surveys or other techniques should show support for the

HOV facility among users, non-users, the general public, and policy makers; a general



perception should exist that the facility is adequately utilized. Since these are two different

elements, it is suggested that one MOE focus on the perception of utilization of the HOV facility

and another MOE focus on the perception of whether it is a good transportation improvement.

The violation rates, or the percentage of vehicles using the HOV facility that do not meet the

minimum occupancy requirement, can also be used as a MOE for this objective.

General Threshold Ranges: It may be difficult to establish a desired threshold level for this

objective. However, a desired level of public acceptance, user acceptance, and non-user

acceptance can be identified and measured through the use of surveys. As a general guideline it

is suggested that a majority of users and non-users should feel the HOV facility is a good

transportation improvement. The perception of the utilization of the facility may be slightly

lower, especially for non-users. In addition, performance measures and thresholds could be

established related to the number of calls and letters received concerning the facility.

Suggested threshold levels for violation rates are less than 10% for exclusive and contraflow

lanes and less than 20% for concurrent flow lanes. It is realized that the violation rates relate

somewhat to capacity and public support issues, enforcement design, and the level of

enforcement.

Data Needs: Data needed to evaluate this objective can be obtained from surveys of users,

non-users, focus groups, and the general public, monitoring of calls and letters, newspaper

articles, other public reactions relating to the facility, violation rates, and enforcement levels.

Much of this information can be gathered through ongoing marketing and public information

programs, which usually contain monitoring and evaluation components. Many of the case

studies support the importance of marketing and public information programs to educate both

the public and policy makers on the purpose and use of the HOV projects.

Objective: The HOV facility should be a cost-effective transportation improvement.

Measure of Effectiveness: The measure most commonly used with this objective is the benefit-

cost ratio.

General Threshold Ranges: A number of different elements such as travel time savings,

operating cost savings, and savings in the cost of congestion can be included as benefits to

calculate the benefit-cost ratio of an HOV facility. It is suggested that a basic guideline is that, if

an HOV facility has a benefit-cost ratio of greater than one based only on the value of travel

time savings by persons using the facility, then the project can be considered cost-effective. It is

realized that this is an extremely conservative approach, since the HOV facility should also

generate other benefits. However, it provides a relatively easy to understand measure and is

based on obtainable information. Some groups have suggested that only the time saved by new

HOV users should be used in calculating the benefit-cost ratio.



Data Needs: In order to develop a benefit-cost ratio, the total cost (capital and operating) of

the project is needed along with a costing of the benefits. As discussed above, it is suggested

that the travel time savings to persons using the facility be used as a primary benefit.

Table 7. Suggested Objectives and Measures of Effectiveness

Objective Measures of Effectiveness

• The HOV facility should improve the capability of a congested freeway corridor to move more people by increasing the number of persons per

vehicle.

• The HOV facility should increase The operating efficiency of bus service in the freeway corridor.

• The HOV facility should provide travel time savings and a more reliable trip time to HOVs utilizing the HOV facility.

• The HOV facility should have favorable impacts

on air quality and energy consumption.

• The HOV facility should increase the per lane

efficiency of the total freeway facility.

• The HOV facility should not unduly impact the

operation of the freeway main lanes.

• Actual and percent increase in the person movement efficiency • Actual and percent increase in average vehicle occupancy rate • Actual and percent increase in carpools and vanpools • Actual and percent increase in bus riders

• Improvement in vehicle productivity (operating cost per vehicle-mile, operating cost per passenger, operating cost per passenger mile) • Improved bus schedule adherence (on-time performance) • Improved bus safety (accidents rates)

• The peak-period, peak-direction travel time in the HOV lane(s) should be less then the travel time in adjacent freeway lanes • Increase in travel time reliability for vehicles

using HOV lane(s)

• Reduction in emissions • Reduction in total fuel consumption • Reduction in the growth of vehicle miles of

travel (VMT) and vehicle hours of travel

• Improvement in the peak-hour per lane

efficiency of the total facility

• The level of service in the freeway main lanes

should not decline



•The HOV facility should be safe and should not unduly impact the safety of the freeway general- Purpose main lanes.

• The HOV facility should have public support.

• The HOV facility should be cost-effective

transportation improvements.

• Number and severity of accidents for HOV and freeway lanes • Accident rate per million vehicle miles of travel • Accident rate per million passenger miles of

travel

• Support for the facility Among users, non-users, general public, and policy makers • Violation rates (percent of vehicles not meeting

the occupancy requirement)

• Benefit-cost ratio



Chapter 4: Case Study: The Evolution of the Houston HOV System

HOV facilities are an important element of the transportation system in Houston. HOV lanes

and supporting facilities are in operation in six freeway corridors. Building on the success of the

HOV facilities, managed lanes are being developed in one freeway corridor and are under

consideration in a second corridor.

The Federal Highway Administration (FHWA) sponsored this study examining the

development and operation of the HOV system in Houston and the evolution toward managed

lanes. This report summarizes the background and the current status of the Houston HOV

system and the development of the first managed lanes project. It also highlights some of the

issues that may need to be addressed in considering managed lanes.

This study accomplishes a number of objectives. The first objective of the study is to

describe the development, operation, and use of the HOV system in the Houston area and the

evolution toward managed lanes. This report provides an overview of the development and use

of the HOV system and the institutional arrangements that have helped foster the evolution of

the system. A final study objective is to describe some of the issues typically associated with

HOV facilities and managed lanes.

The development and operation of HOV facilities have evolved over the past 30 years.

The opening of the bus-only lane on the Shirley Highway (I-395) in Northern

Virginia/Washington, D.C. in 1969 and the contraflow bus lane on the approach to New York-

New Jersey=s Lincoln Tunnel in 1970 represent the first freeway HOV applications in the

country. Today there are some 130 HOV freeway projects in 23 metropolitan areas in North

America, including Houston.

Managed lanes are also used in some metropolitan areas and are being considered in

other regions. The Interstate system, which was developed to provide high-speed travel with

limited access, represents the most common example of managed lanes. More recently,

managed lanes have reemerged in new and different ways in urban areas throughout the

country.

There is no one common definition of managed lanes. The term managed lanes is being

used in many areas to describe facilities or lanes developed and operated in special ways.

Managed lanes may focus on serving special user groups, such as HOVs or trucks; value pricing

or tolling options; express lanes; and limited access facilities.



According to The Texas Department of Transportation, “A managed lane facility is one

that increases freeway efficiency by packaging various operational and design actions. Lane

management operations may be adjusted at any time to better match regional goals.”

According to The Washington State Department of Transportation (WSDOT) “Managed lanes

facilities include any roadway lane that can be managed to prevent congestion from occurring.

In managed lanes, one or more of these techniques is used to control the number of vehicles

using the lane or roadway:

• Limiting access – providing infrequent on-ramps,

• User eligibility requirements – such as HOV-only, truck-only, permit-only; and

• Pricing – tolls can be varied by time of day to control traffic volumes.

By considering these as different forms of traffic management, it is possible to plan the

best combination of tools to keep a roadway from becoming congested over time, and to

optimize traffic to achieve the best person and vehicle throughput.”

The following facility types and strategies are typically included in general definitions of

managed lanes focusing on preserving enhanced travel conditions:

• HOV lanes;

• High-occupancy/toll (HOT) lanes;

• Value-priced lanes;

• Express lanes;

• Separated or bypass lanes;

• Truck or commercial vehicle lanes;

•Dual roadways, such as physically separated inner and outer roadways in one or both

directions where operation can be managed on at least one of the roadways; and

• Separate toll lanes constructed within freeways.

OVERVIEW OF HOUSTON AREA From the late 1940s through the mid 1970s, the Houston metropolitan area grew at a

rate well above the national average, increasing in population from less than half a million to

over two million. For most of this period, highway and street construction kept a reasonable

pace with growth. By the mid 1970s however, traffic congestion was a significant concern.

During the same period, the city was considering options to purchase the privately owned bus

company, which was reducing service and maintenance levels in the face of financial hardships.

The use of what was then a relatively new and untried concept – high-occupancy vehicle (HOV)

lanes – was considered to address these concerns, and an initial demonstration project on the I-

45 North Freeway was undertaken.

In 2003, some 4.3 million people were living in the 8,800-square mile Houston

metropolitan region, which is characterized by low-density development. In response to



ongoing concerns related to traffic congestion on the freeway system, limited available right-of-

way, and air quality, the initial nine-mile contraflow demonstration project has evolved over an

almost 25-year period into a system that encompasses some 100 miles of HOV lanes, numerous

direct access ramps, 28 park-and-ride lots, four park-and-pool lots, an extensive network of

express bus service, and a value pricing demonstration project. This system provides

preferential treatment to buses, vanpools, and carpools in the major freeway corridors. The

HOV system represents part of a multifaceted approach being taken in the Houston area to

manage traffic congestion and to improve mobility. Building on the success of the HOV system,

a value pricing demonstration was initiated in two corridors and managed lanes are being

developed in one corridor. Other improvements to the surface transportation system include

expanding freeways and roadways, building new toll roads, and developing an advanced

transportation management system (TranStar). Future plans include additional HOV facilities,

considering managed lanes in other corridors, expanding the LRT system, examining commuter

rail, additional toll roads, and expanding TranStar.

Planning, designing, operating, and enforcing the HOV system elements has been

accomplished through the coordinated efforts of the Texas Department of Transportation

(TxDOT) and the Metropolitan Transit Authority of Harris County (METRO). Recently, Harris

County and the Harris County Toll Road Authority (HCTRA) have joined this partnership to assist

with the development and operation of the planned managed lanes. These efforts have been

coordinated with the Houston-Galveston Area Council (HGAC), the metropolitan planning

organization (MPO) for the area.

METHODOLOGY ADOPTED FOR CASE STUDY A number of activities were completed as part of this study. First, available reports, papers,

and other documents on the Houston HOV and managed lane facilities were reviewed. The

HOV system has been the focus of ongoing monitoring efforts supported by TxDOT and METRO.

As a result, a good deal of information is available on the use of the system. Second, additional

information was obtained through communication with representatives from agencies and

organizations in the Houston area. No further original data collection was conducted due to

the limited project scope. Third, information from the Houston case study was synthesized and

combined with information on managed lanes in other areas to highlight some of the issues

typically associated with HOV and managed lanes.

EVOLUTION AND USE OF THE HOUSTON HOV LANE SYSTEM

Development and Operation of the HOV Lane System

In 1970s, The Texas Highway Department (THD) was planning expansions to many freeways and

examining possible improvements to others. At the same time, the privately-owned bus



company was encountering serious financial difficulties. As a result, service levels were low and

buses were in poor conditions.

In the early 1970s, A long-range transit plan was prepared, which included an extensive

rail system and HOV lanes on some freeways, Which was defeated by voters. In 1974, the City

purchased the privately-owned bus company and established the Office of Public

Transportation (OPT).

OPT and THD shared a common interest in addressing increasing levels of traffic

congestion by encouraging greater use of buses, vanpools, and carpools. THD was concerned

about improving travel conditions on congested freeways and OPT was interested in methods

to move buses through traffic more efficiently and to improve services levels and the image of

the bus system. Using a federal Service and Methods Demonstration (SMD) grant, the OPT and

THD examined the potential of freeway HOV lanes, which were a relatively new concept at the

time. A contraflow lane demonstration project on the North (I-45 North) Freeway was

recommended to test the HOV concept.The I-45 N corridor had a high directional split and

travel in the peak direction was very congested. Thus, the corridor provided the right

conditions for the demonstration. The demonstration project included a nine-mile contraflow

HOV lane, park-and-ride lots, freeway ramp metering, and contracted bus service.

During the development of the contraflow lane the city continued to work toward

establishing a regional transit agency. In 1978, voters approved the creation of the

Metropolitan Transit Authority of Harris County (METRO) and the dedication of one percent of

the local sales tax to fund the agency. The 1978 Regional Transit Plan, which identified the

projects METRO would pursue, included HOV facilities in most freeway corridors, as well as rail

transit. The HOV facilities included in this plan have been incorporated and refined in METRO,

TxDOT, and Houston-Galveston Area Council (HGAC) plans over the years. With the creation of

METRO, OPT was dissolved in 1979. The contraflow lane began operation in August 1979.

Figure 2 shows the location of the contraflow lane. The lane operated from 5:45 a.m. to 8:45

a.m. in the inbound direction toward downtown and from 3:30 p.m. to 7:00 p.m. in the

outbound direction. The contraflow lane was created by taking the inside freeway lane in the

off-peak direction of travel for use by buses and vanpools traveling in the peak-direction. The

lane was separated from opposing traffic by plastic pylons, which were set up and removed by

METRO crews each morning and afternoon.

Figure 2. Location of I-45 North Contraflow Lane.



Due to safety concerns, only buses and

authorized vanpools were allowed to use

the contraflow lane. Figure 3 highlights

the operation of the lane. To become

eligible to use the lane, vanpool drivers

had to register and complete training

provided by METRO. During the late

1970s and early 1980s, many large

downtown employers subsidized vanpools

for their employees in response to the

Arab Oil Embargo in 1979. Enforcement

of Figure 3. I-45 North

Contraflow Lane.

the lane was initially

contracted to the Houston

Police Department. METRO

established its own transit

police force in 1982 and

assumed enforcement duties

of the contraflow lane at that

time. METRO also provided

wreckers at strategic locations

along the lane to deal with any

accidents or incidents.

Some 8,000 bus riders and

vanpoolers used the lane on a daily basis during the first few years of the project. During the

morning peak hour. A 3.3-mile concurrent flow lane upstream from the entrance to the

contraflow lane was opened in 1981. Use levels increased to a high of 15,000 riders per day

with this improvement.

The success of the demonstration project resulted in a permanent HOV facility on the

North Freeway and the consideration of HOV lanes on other freeways. The demonstration

proved that commuters would change from driving alone to taking the bus or riding in a

vanpool. Survey results indicate that some 35 to 39 percent of bus riders and 30 to 42 percent

of vanpoolers previously drove alone.



In September of 1984, the first segment of the permanent HOV lane opened and

operation of the contraflow lane ceased.

The development of the second HOV lane in Houston took advantage of a planned

improvement project. Plans to repair and overlay a 10-mile segment of the Katy Freeway were

moving forward in the late 1970s, with a major reconstruction effort anticipated in the future.

An HOV lane on the Katy Freeway had been identified in the 1978 Regional Transit Plan. To

take advantage of the opportunity presented by the repair project, the design of the HOV lane

was expedited and the overlay project was delayed slightly. Working jointly, the SDHPT and

METRO completed the design and construction process, including obtaining the necessary

federal approvals, and the first 4.7-mile segment of the Katy HOV lane was opened in October

of 1984. Figure 4 shows the location of the Katy HOV lane and the HOV system in 1985.

The lane initially operated inbound from 5:45 a.m. to 9:30 a.m. and outbound from 3:30

p.m. to 7:00 p.m. Operating hours were extended to 5:45 a.m. to 11:00 a.m. and 2:00 p.m. to

7:00 p.m. in 1986. Following the vehicle eligibility requirements in use on I-45 North, only

buses and vanpools were initially allowed to use the Katy HOV lane. Only 66 vanpools and 20

buses, for a total of 86 vehicles, used the lane during the morning peak hour with these

requirements. To address this low use, the lane was open to authorized 4+ carpools in 1985.

The occupancy requirement was dropped to 3+ carpools later in 1985 and to 2+

carpools in 1986. Table 2 highlights the initial changes in vehicle eligibility and vehicle-

occupancy levels and corresponding use levels.

Figure 4. 1985 Houston HOV Lane System



Table 2. Changes in Vehicle Occupancy Requirements and Corresponding Vehicle Volumes on the Katy HOV Lane

Figure 5. 1995 Houston HOV Lane System

The HOV system expanded significantly from 1985

to 2003. Figures 5 and 6 illustrate the growth in the

HOV system over this 18-year period. METRO and

the renamed Texas Department of Transportation

(TxDOT) continued to work cooperatively on the

development and operation of the HOV system.

Funding from METRO, TxDOT, FHWA, and FTA was

used for different parts of the system. Figure 6. 2003 Houston HOV Lane Syste



By 2003, some 100 miles of HOV lanes are in operation in six freeway corridors. The main

elements of the HOV system – the HOV lanes, park-and-ride lots, transit centers, direct access

ramps, and express bus service.

• HOV Lanes. The HOV lanes are primarily one-lane, reversible, barrier-separated facilities,

located in the median of six freeways. A short two-lane, two-direction section exists on the

Northwest (US 290) Freeway. A two-way facility, with one lane in each direction of travel, is in

operation on the Eastex (US 59) Freeway. A concurrent flow HOV lane is in operation on the

Katy Freeway, leading to the reversible lane.

The lanes operate in the inbound direction from 5:00 a.m. to 12:00 p.m. and in the outbound

direction from 2:00 p.m. to 9:00 p.m. The lanes are closed from Noon to 2:00 p.m. to reverse

operations and are closed to all traffic at other times. A 2+ vehicle-occupancy requirement is

used on all the HOV facilities, except the Katy and the Northwest. These two HOV lanes have a

3+ occupancy requirement from 6:45 a.m. to 8:00 a.m. and 5:00 p.m. to 6:00 p.m., due to

congestion occurring at the 2+ level. The Quick Ride value-pricing project operates on these

two lanes, allowing participating 2+ carpools use of the lane for a $2.00 per trip fee.

• Park-and-Ride Lots. A total of 28 park-and-ride lots and four park-and-pool lots are

located in the six corridors with HOV lanes. The larger park-and-ride lots have direct access to

the HOV lanes and transit stations with passenger amenities. There are spaces for between 900

and 2,500 automobiles at 19 of the lots. The number of parking spaces at lots in each corridor

range from slightly over 3,000 to almost 7,500.

• Transit Centers. The park-and-ride lots have transit stations with covered passenger

waiting areas and other amenities. Transit centers without park-and-ride lots or with only small

lots are located at strategic transfer points.

• Direct Access Ramps. As Figure 9 illustrates, direct access ramps connect the major park-

and-ride lots and transit stations to the HOV lanes. These ramps provide travel time savings for

buses using the HOV lanes and enhance the safe operation of both the HOV lanes and the

freeways. Use of the direct access ramps is restricted to buses, carpools, and vanpools during

operating hours. The ramps are closed during non-operating periods. Carpools and vanpools

can access the ramps and the HOV lanes through the lots. The direct access ramps provide

significant travel time savings for buses and other HOVs. The 1990 opening of the direct access

ramp linking the Northwest Station park-and-ride lot with the Northwest HOV lane provided

travel savings of 14 minutes for vehicles entering and exiting the HOV lane. Prior to the ramp

opening, HOVs had to travel local streets, enter the freeway, and merge across the general-

purpose lanes to enter the HOV lane. Use levels increased after the ramp opened.



• Express Bus Service. METRO provides a high level of bus service in each corridor, with

frequent trips from the major park-and-ride lots. Over-the-road coaches are operated on many

routes, as are articulated buses. Although there is not direct evidence linking increased

ridership to use of the coaches, surveys of bus riders indicate support for their use and support

for frequent service. The HOV lanes and express bus services are oriented primarily in a radial

direction, with downtown Houston as the major destination. The express bus system has

evolved over the years, however, providing service to major activity centers such as the Texas

Medical Center (TMC), Greenway Plaza, and the Post Oak/Galleria area. More recently, reverse

commute services have been added in some corridors, taking advantage of buses in the

general-purpose lanes deadheading back to park-and-ride lots.

• Rideshare Services and Other Supporting Activities. METRO provides rideshare

services in the Houston area. METRO’s RideShare program includes a number of elements to

help individuals form carpools and vanpools. Rideshare matching services are available by

telephone and on-line through METRO’s Internet site. The METROVan program helps

commuters form vanpools and provides vans for their use. METROVan is co-sponsored by

HGAC, allowing METRO to provide vanpools outside the METRO service area. METRO’s

corporate RideSponsor program focuses on encouraging employees to commute to work by

bus, carpools, or vanpools. The program provides computerized ridematching services,

vanpools, and employer outreach. Corporate RideSponsors are eligible for discounted bus

passes for their employees.

USE OF THE HOV LANE SYSTEM

The monitoring program focuses primarily on HOV and freeway vehicle volumes, bus ridership

levels, vehicle occupancy levels, travel times in the HOV lanes and the freeway lanes, and

incident data. Periodic surveys of bus riders, carpoolers, and vanpoolers using the HOV lanes,

and motorists in the general-purpose lanes have been conducted.

• Use Levels. Table 2 presents key information on use of the Houston HOV lanes. In 2003,

some 212,079 passengers used the HOV lanes on a daily basis. Buses carried 43,225

passengers, vanpools accounted for 2,500 riders, carpools had 74,867 occupants, and 407

motorcycles used the lanes daily. Morning peak-hour utilization levels range from

approximately 1,000 vehicles on the Katy HOV lane to 1,551 on the Northwest HOV lanes.



Table 3. 2003 Houston HOV Lane Parameters and Weekday Utilization Data

Corresponding person volumes in the morning peak hour average between 3,424 on the

Gulf HOV lane and 4,836 on the North HOV lane. The HOV lanes account for 40 percent of the

morning peak hour total person movement on three of the freeways. The AM peak hour is

defined as the hour with the highest vehicle volumes. As a result, the peak hour may vary by

HOV lane.

Vehicle-occupancy requirements were adjusted on two HOV lanes due to high levels of

use. By 1988, morning peak hour vehicle volumes on the Katy HOV lane were frequently

approaching or exceeding 1,500 vehicles, which resulted in degradation in facilities.

A policy-level decision was made by both agencies to increase the vehicle-occupancy

requirement from 2+ to 3+ during the period from 6:45 to 8:15 a.m. The 2+ requirement was

maintained at other times. This change was implemented on very short notice in October 1988.

Table 4 highlights the changes in vehicle volumes immediately after the change to the 3+

requirement in 1988 and the growth in 3+ carpools over the next eight years. The morning

peak hour carpool volume dropped from some 1,450 to 510 vehicles immediately after the

change, representing a 65 percent reduction. Total AM peak hour vehicle volumes – carpools,

vanpools, and buses – dropped from 1,511 to 570, a 62 percent reduction. Person volumes

declined by 33 percent during the AM peak hour. Although vehicle and person volumes

declined, AM peak hour average vehicle occupancy (AVO) increased from 3.1 prior to the

change to 4.5 five months after the change.



Table 4. Change to 3+ Occupancy Requirement on the Katy HOV Lane

Vehicle volumes during the 6:00 a.m. to 9:00 a.m. peak-period declined by some 14

percent. Two person carpools declined by some 41 percent and 3+ carpools increased by 68

percent. Bus ridership grew by eight percent. Based on survey results, it appears that some

two person carpools shifted their travel to earlier time periods and some changed their travel

routes to use the newly opened Northwest HOV lane, which had a 2+ requirement.

The time period for the 3+ restriction on the Kay HOV lane has been modified over time.

In May 1990, the 3+ period was shortened to 6:45 a.m. to 8:00 a.m. In September 1991, the 3+

restriction was implemented in the afternoon peak hour from 5:00 p.m. to 6:00 p.m. A 3+

restriction was also implemented from 6:45 a.m. to 8:00 a.m. on the Northwest HOV lane in

July 1999 in response to congestion levels similar to those experienced on the Katy HOV lane.

• Bus Operating Speeds and Schedule Times. The HOV lanes and direct access ramps have

significantly increased METRO bus operating speeds. The peak hour bus operating speeds have

almost doubled, from 26 mph to 54 mph, resulting in significant reductions in bus schedule

times. Examples of reductions in the morning peak hour schedule time for buses from park-

and-ride lots to downtown Houston include from 45 to 24 minutes from the Addicks park-and-

ride lot on the Katy HOV lane, from 40 to 25 minutes from the Edgebrook park-and-ride lot on

the Gulf HOV lane, and from 50 to 30 minutes from the Northwest Station park-and-ride lot on

the Northwest HOV lane.

• Travel Time Savings. The HOV lanes provide travel time savings for buses, vanpools, and

carpools. Morning peak hour travel time savings range from approximately 2 to 22 minutes on

the different HOV lanes. The Northwest Freeway HOV lane generally provides the largest travel

time savings of about 22 minutes. The Katy HOV lane averages between 17 and 20 minutes, the

North 14 minutes, and the Gulf and Southwest between 4 and 2 minutes. In addition, the HOV

lanes provide more reliable trip times to carpoolers, vanpoolers, and bus riders.

• Park-and-Ride Lots. Approximately 32,293 spaces are provided at 28 park-and-ride lots

associated with the HOV lanes. An additional 1,377 spaces are located at four park-and-pool



lots. METRO buses serve the park-and-ride lots, while the park-and-pool lots provide staging

areas for carpools and vanpools. In 2003, the overall occupancy levels at the individual facilities

ranged from about 10 percent at some park-and-pool lots to 100 percent at well-used park-

and-ride lots. Table 5 highlights the growth in the number of park-and-ride lots and use levels

from 1980 to 2003. From 1980 to 1990, the number of park-and-ride lots doubled from 10 to

20. The number of available spaces increased from 4,070 spaces to 12,626 spaces. Use of the

lots grew from 4,070 parked vehicles to 12,626 vehicles. As of 2003, there are 28 park-and-ride

lots, with 32,293 spaces. Approximately 54 percent of the available spaces are used on a daily

basis. Table 6 highlights the number of park-and-ride spaces, and the occupancy levels by

corridor.

• Change in Travel Mode. The travel time savings and the improved trip time reliability have

influenced commuters to change from driving alone to taking the bus, carpooling, and

vanpooling. Periodic surveys of HOV lane users show that between 36 and 45 percent of

current carpoolers formerly drove alone, while 38 to 46 percent of bus riders previously drove

alone. Surveys conducted in 1988, 1989, and 1990, indicate that the opening of the HOV lanes

was very important in their decision to ride a bus for between 54 and 76 percent of the bus

riders using the Houston HOV lanes. Between 22 and 39 percent of the respondents also

indicated that they would not be riding the bus if the HOV lane had not been opened.

• Average Vehicle Occupancy. The HOV system has resulted in an increase in AVO levels in the

corridors with HOV lanes. For example, the morning peak-hour AVO increased on the North

Freeway from 1.28 in 1978 before the contraflow HOV lane opened to 1.41 in 1996. The

morning peak-hour AVO increased on the Northwest Freeway from 1.14 in 1987 prior to the

opening of the HOV lane to 1.36 in 1996. The 1996 morning AVO for the HOV lanes ranged

from 2.6 to 3.65, compared to 1.02 to 1.12 for the general-purpose lanes.

Table 5. Houston HOV Lane Park-and-Ride Lot Capacity and Utilization



Table 6. Houston HOV Lane Park-and-Ride Lot Capacity and Utilization by Corridor

• Positive Public Perception. Periodic surveys of HOV lane users and motorists in the general-

purpose lanes included questions designed to obtain feedback on the general perception

toward the HOV lanes and support for these facilities. Between 40 and 81 percent of motorists

in the general-purpose lanes on freeways with HOV facilities and one freeway without an HOV

lane have responded positively to these surveys that the HOV facilities are a good

transportation improvement. since funding from both had been used for the Katy HOV lane and

supporting elements.

ISSUES TO BE CONSIDERED FOR DEVELOPING AND OPERATING MANAGED

LANES A number of issues may need to be examined when HOV and managed lanes are being

considered in an area or when changes to an existing facility are being contemplated. While

many of these issues are similar to those associated with HOV facilities or other transportation

improvements, some are unique to the special characteristics of managed lanes.

Those issues are as follows:

Defining Project Goals and Objectives Identifying User Groups

Design Elements Pricing and Equity

Legislation Policy Maker Support

Public Involvement Transit Service

Institutional Relationships Enforcement

Performance Monitoring Incident Management

ONGOING CONSIDERATION OF ENHANCEMENTS Current and Future Activities

FHWA and other groups have begun a variety of activities related to managed lanes.

Additional activities are planned to help share information related to managed lanes and to



help advance the state-of-the-practice. This section highlights a few examples of FHWA-

sponsored activities.

• Managed Lanes: A Cross-Cutting Study. FHWA is sponsoring the development of a report

examining the types of managed lanes and potential issues associated with different

approaches in more detail. The report, which will be available in late 2003, provides a

definition of managed lanes, highlights examples of managed lane projects throughout the

country, and describes some of the elements associated with planning and operating managed

lanes.

• Managed Lanes Primer. FHWA is sponsoring the development of a Managed Lanes Primer.

This document, which will be available in early 2004, highlights key aspects of managed lanes,

potential benefits, possible issues, and best practice case studies.

• Managed Lanes Initiative. FHWA is developing a managed lanes initiative that will identify

policy, program, and research elements to help advance managed lanes. A November 2003

workshop involving selected transportation professionals from throughout the country will help

in the development of the initiative.



References:

• Houston Managed Lanes Case Study: The Evolution of the Houston HOV System (U.S.

Department Of Transportation)

• SUGGESTED PROCEDURES FOR EVALUATING THE EFFECTIVENESS OF FREEWAY HOV

FACILITIES (Texas State Department of Highways and Public Transportation)

• An Assessment of High Occupancy Vehicle (HOV) Facilities in North America (U.S.

Department Of Transportation)

• Potential Impact of Exempt Vehicles on HOV Lanes (Federal Highway Administration By

the Texas Transportation Institute.

• Federal Highway Administration. Federal-Aid Highway Program Guidance on High-

Occupancy Vehicle (HOV) Lane.

• High-Occupancy Vehicle Enforcement Task Force. Report of the High-Occupancy Vehicle

Enforcement Task Force, Virginia Department of Transportation, Richmond, Virginia,

August 15, 2003.

• A Guide For HOT Lane Development (U.S. Department Of Transportation

High Occupancy Vehicle Lanes

Documents

highoccupancy vehicle

high occupancy lane

commuter lanes

diamond lanes

carpool lanes

anaged lanes

new highway lanes

available hov