HOV lane

A high-occupancy vehicle lane (also known as a HOV lane, carpool lane, diamond lane, and transit lane or T2 or T3 lanes in Australia and New Zealand) is a restricted traffic lane reserved at peak travel times or longer for exclusive use of vehicles with a driver and one or more passengers, including carpools, vanpools and transit buses. The normal minimum occupancy level is 2 or 3 occupants. Many jurisdictions exempt other vehicles, including motorcycles, charter buses, emergency and law enforcement vehicles, low emission and other green vehicles, and/or single-occupancy vehicles paying a toll. HOV lanes are normally created to increase higher average vehicle occupancy and person throughput with the goal of reducing traffic congestion and air pollution  although their effectiveness is questionable.

Regional and corporate sponsored vanpools, carpools, and rideshare communities give commuters a way to increase occupancy. For places without such services, online rideshare communities can serve similar purpose. Slugging lines are common in some places, where solo drivers pick up a passenger to share the ride and allow use of the HOV lane. High occupancy toll lanes (HOT lanes) have been introduced in the United States to allow solo driver vehicles to use the lane on payment of a variable fee which usually varies with demand. Motorcycles are permitted in the HOV lanes for safety reasons.

History
The introduction of HOV lanes in the U.S. progressed slowly during the 1970s and early 1980s. Major growth occurred from the mid-1980s to the late 1990s. The first freeway HOV lane in the United States was implemented in the Henry G. Shirley Memorial Highway in Northern Virginia, between Washington DC and the Capital Beltway, and was opened in 1969 as a bus-only lane. The busway was opened in December 1973 to carpools with four or more occupants, becoming the first instance in which buses and carpools officially shared a HOV lane over a considerable distance.
 * United States

As of 2005, the two lanes of this HOV 3+ facility were carrying during the morning peak hour (6:30 am to 9:30 am) a total of 31,700 people in 8,600 vehicles (3.7 persons/veh) while the 3 or 4 general purpose lanes carried 23,500 people in 21,300 vehicles (1.1 persons/veh). Average travel time in the HOV facility is 29 min while 64 min in the general traffic lanes. As of 2012, the I-95/I395 HOV facility is 30 mi long and extends from Washington, D.C. to Dumfries, Virginia, has two reversible lanes separated from the regular lanes by barriers, with access through on and off elevated ramps. Three or more people in a vehicle (HOV 3+) are required to travel on the facility during rush hours on weekdays.

The second freeway HOV facility was the contraflow bus lane on the Lincoln Tunnel Approach and Helix in Hudson County, New Jersey in 1970. According to the Federal Highway Administration (FHWA), the Lincoln Tunnel XBL is the country's HOV facility with the highest number of peak hour persons among HOV facilities with utilization data available, with 23,500 persons in the morning peak, and 62,000 passengers during the 4-hour morning peak.

The first permanent HOV facility in California was the bypass lane at the San Francisco-Oakland Bay Bridge toll plaza, opened to the public in April 1970. The El Monte Busway (I-10 / San Bernardino Freeway) in Los Angeles was initially only available for buses when it opened in 1973. Three-person carpools were allowed to use the bus lane for 3 months in 1974 due to a strike by bus operators and then permanently at a 3+ HOV from 1976. It is one of the most efficient HOV facilities in North America and it currently being converted to High occupancy toll lane operation to allow low-occupancy vehicles to bid for excess capacity on the lane in the Metro ExpressLanes project.

Beginning in the 1970s, the Urban Mass Transit Administration recognized the advantages of exclusive bus lanes and encouraged their funding. In the 1970s the FHWA began to allow state highway agencies to spend federal funds on HOV lanes. As a result of the 1973 Arab Oil Embargo, interest in ridesharing picked up and the states began experimenting with HOV lanes. In order to reduce crude oil consumption, the 1974 Emergency Highway Energy Conservation Act mandated maximum speed limits of 55 mph on public highways and became the first instance where the U.S. federal government began providing funding for ridesharing and states were allowed to spend their highway funds on rideshare demonstration projects. The 1978 Surface Transportation Assistance Act made funding for rideshare initiatives permanent.

Also during the early 1970s, ridesharing was recommended for the first time as a tool to mitigate air quality problems. The 1970 Clean Air Act Amendments established the National Ambient Air Quality Standards and gave the Environmental Protection Agency (EPA) substantial authority to regulate air quality attainment. A final control plan for the Los Angeles Basin was issued in 1973, and one of its main provisions was a two-phase conversion of 184 mi of freeway and arterial roadway lanes to bus/carpool lanes and the development of a regional computerized carpool matching system. However, it took until 1985 before any HOV project was constructed in Los Angeles County, and by 1993 there were only 58 mi of HOV lanes countywide.

A significant policy shift took place in October 1990, when a memorandum from the FHWA administrator stated that "FHWA strongly supports the objective of HOV preferential facilities and encourages the proper application of HOV technology." Regional administrators were directed to promote HOV lanes and related facilities. Also in the early 1990s two laws reinforced the U.S. commitment to HOV lane construction. The Clean Air Act Amendments of 1990 included HOV lanes as one of the transportation control measures that could be included in state implementation plans to attain federal air quality standards. The 1990 amendments also deny the administrator of the EPA the authority to block FHWA from funding 24-hour HOV lanes as part of the sanctions for a state's failure to comply with the Clean Air Act, if the secretary of transportation wishes to approve the FHWA funds.

On the other hand, the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991 encouraged the construction of HOV lanes, which were made eligible for Congestion Mitigation and Air Quality (CMAQ) funds in regions not attaining federal air quality standards. CMAQ funds may be spent on new HOV lane construction, even if the HOV designation holds only at peak travel times or in the peak direction. ISTEA also provided that under the Interstate Maintenance Program, only HOV projects would receive the 90% federal matching ratio formerly available for the addition of general purpose lanes. And ISTEA permitted state authorities to define a high occupancy vehicle as having a minimum of two occupants (HOV 2+).

As of 2009, California, with 88 HOV facilities, was the state with the most HOV lanes in the country, followed by Minnesota with 83 facilities, Washington State with 41, Texas with 35, and Virginia with 21. The only active U.S. facility with two HOV lanes in each direction is I-110 between Adams Blvd. and SR 91 in Los Angeles. By 2006 HOV lanes in California were operating at two-thirds of their capacity, and these HOV facilities carried on average 2,518 persons per hour during peak hours, substantially more people than a congested general traffic lanes. As of 2008, the longest HOV facility in operation was the I-95 between SR 112 and Gateway Boulvard in Miami, Florida, with 116.0 mi of lanes in a route of 58.0 mi. This facility will be exceeded by the HOV facility under construction in the I-495 Capital Beltway in the Washington D.C. Metropolitan Area that will have two HOV lanes in each direction with elevated on/off ramp access, for a total of 224.0 mi of HOV lanes in a route of 56.0 mi.

As of 2012, there are some 126 HOV facilities on freeways in 27 metropolitan areas in the United States, which includes over 1,000 corridor miles (1,600 km).

The first HOV facilities in Canada were opened in Greater Vancouver and Toronto in the early 1990s, followed shortly by Ottawa, Gatineau, Montreal and later by Calgary. As of 2010 there were around 150 km of highway HOV lanes in 11 locations in British Columbia, Ontario and Quebec, and over 130 km of arterial HOV lanes in 24 locations in Greater Vancouver, Calgary, Toronto, Ottawa and Gatineau. The Ontario Ministry of Transportation (MTO) estimated in 2006 that commuters in Toronto using the HOV facilities on Highways 403 and 404 were saving between 14 to 17 minutes per trip compared to their travel time before the HOV lanes opened. The MTO also estimated that there were almost 40% of commuters carpooling on Highway 403 eastbound in the morning peak hour compared to only 14% in 2003; and 37% of commuters carpool on Highway 403 westbound in the afternoon peak hour compared to only 22% in 2003. The average rush hour speed on the HOV lanes is 100 kph compared to 60 kph in general traffic lanes on Highway 403.
 * Canada

As of 2012 there are a few HOV lanes in operation in Europe. The main reason is that in general European cities have far better public transport services and fewer high capacity multi-lane urban motorways than the U.S. and Canada. However, at around 1.3 persons per vehicle, average car occupancy is relatively low in most European cities. The emphasis in Europe has been on providing bus lanes and on-street bus priority measures. The first HOV lane in Europe was opened in the Netherlands in October 1993 and operated until August 1994. The HOV facility was a 7 km barrier-separated HOV 3+ on the A1 near Amsterdam. The facility did not attract enough users to overcome public criticism and was converted to a reversible lane open to the general traffic after the judge in a legal test case ruled that Dutch traffic law lacked the concept of a car pool and thus that the principle of equality was violated.
 * Europe

Spain was the next European country to introduced high-occupancy vehicle lanes, when median reversible HOV lanes were opened in Madrid's N-VI National Highway in 1995. This facility is Europe's oldest HOV facility still in operation. The first HOV facility in the United Kingdom opened in Leeds in 1998. The facility was implemented on A647 road near Leeds, as an experimental scheme but it became permanent. The HOV lanes is 1.5 km long and operates as a HOV 2+ facility. A 2.8 km HOV 3+ facility opened in Linz, Austria in 1999. Sweden opened its first HOV lane in Stockholm in 2000, an 8 km HOV 3+ facility. The first HOV lane in Norway was implemented in May 2001 as a HOV 3+ on Elgeseter Street, an undivided four-lane arterial road in Trondheim. This facility was followed by HOV lanes implemented in Oslo and Kristiansand.


 * New Zealand and Australia

The first HOV lane or transit lane opened in Australia in February 1992. This HOV 2+ lane is located on the Eastern Highway in Melbourne. As of 2012 there are also HOV facilities in Sydney and Brisbane.

In Auckland, New Zealand, there are several short HOV 2+ and 3+ lanes throughout the region, commonly known as T2 and T3 lanes. There is a T2 transit lane in Tamaki Drive, in a short stretch between Glendowie and downtown Auckland. There are also T2 priority lanes on Auckland's Northern, Southern, Northwestern and Southwestern Motorways. These priority lanes are left side on-ramp lanes heading towards the motorway, where vehicles with 2 or more people can bypass the ramp meter signal. Priority lanes can also be used by trucks, buses and motorcycles, and the priority lanes can be used by carpoolers at any time. There are also several short T2 and T3 facilities in North Shore City operating during rush hours.

In Jakarta, HOV 3+ is known as Three in One (Tiga dalam satu), first implemented by governor Sutiyoso. HOV 3+ is implemented on weekdays in existing roads of Sisingamangraja Road (fast and slow lane), Jenderal Sudirman Road (fast and slow lane), MH. Thamrin Road (fast and slow lane), Medan Merdeka Barat Road, Majapahit Road, Gajah Mada Road, Pintu Besar Selatan Road, Pintu Besar Utara Road, Hayam Wuruk Road, and section of Jalan Jenderal Gatot Subroto. The policy was originally implemented only between 07:00 and 10:00. Since the introduction of Jakarta's bus rapid transit in December 2003, the policy was extended from 07:00 to 10:00 and 16:00 to 19:00. In September 2004, the evening time is changed to 16:30–19:00.
 * Indonesia

Design and operations
HOV lanes may be a single traffic lane within the main roadway with distinctive markings, or alternatively as a separate roadways with one of more traffic lanes either parallel to the general lanes or alternatively grade-separated, above or below, the general lanes. Interstate 110 (California) has four HOV lanes on an upper deck.

HOV bypass lanes to allow carpool traffic to bypass areas of regular congestion in many places and a HOV lane may operate as a reversible lane, working in the direction of the dominant traffic flow in both the morning and the afternoon. All lanes of a 10 mi section of the Interstate 66 in the suburbs of Washington, D.C. are treated as a HOV during the rush hour in the primary direction of flow.

The traffic speed differential between HOV and general purpose lanes creates a potentially dangerous situation if the HOV lanes are not separated by a barrier. A Texas Transportation Institute study found that HOV lanes lacking barrier separations caused a 50% increase in injury crashes.

High occupancy toll lane
High occupancy toll lanes As some HOV lanes were not utilized to its full capacity, users of low or single-occupancy vehicles have been allowed to use a high-occupancy vehicle lane if they pay a toll. This scheme is known as high-occupancy toll (HOT) lanes, and it has been introduced mainly in the United States. The first practical implementations was California's formerly private toll 91 Express Lanes, in Orange County, California in 1995, followed in 1996 by Interstate 15 north of San Diego. According to the Texas A&M Transportation Institute, by 2012 there were in the United States 294 corridor-miles of HOT/Express lanes and 163 corridor-miles of HOT/Express lanes under construction.



The solo drivers are allowed to use the HOV lanes upon payment of a fee that varies based on demand. The tolls change throughout the day according to real-time traffic conditions, which is intended to manage the number of cars in the lanes to maintain good journey times.

Proponents claim that all motorists will benefit from HOT lanes, even those who choose not to use them. This argument only applies to projects that increase the total number of lanes. Proponents also claim that HOT lanes provide an incentive to use transit and ride sharing. There has been controversy over this concept, and HOT schemes have been called "Lexus" lanes, as critics see this new pricing scheme as a perk to the rich.

HOT tolls are collected either by manned toll booths, automatic number plate recognition, or electronic toll collection systems. Some systems use RFID transmitters to monitor entry and exiting of the lane and charges drivers depending on demand. Typically, these tolls increase as traffic density and congestion within the tolled lanes increases, a policy known as congestion pricing. The goal of this pricing scheme is to minimize traffic congestion within the lanes.

Qualifying vehicles
Qualification for HOV status varies by scheme, however the following vehicles may be included:
 * Private cars and taxis with a minimum number of occupants (often 2 or 3), including babies of any age (but only after birth).
 * Single occupant green vehicles, such as hybrid electric vehicles, plug-in hybrids, and battery electric vehicles.
 * Single occupancy vehicles upon payment of a variable fee (high occupancy toll lane only).
 * Motorcycles.
 * Buses designed to transport sixteen or more passengers, including the driver.
 * Emergency vehicles (fire, ambulance, rescue) and law enforcement vehicles.
 * Public utility vehicles when responding to emergency calls.
 * Bicycles.

In various places a system of slugging has developed where drivers pick up one or more additional passengers at pre-arranged "slug lines"; the driver shouts out his destination, and people in the line going to that destination enter the car on a first-come-first-served basis.

Compliance, enforcement and avoidance
Fines are usually imposed on drivers of non-qualifying vehicles who use the lanes.

In the early years, drivers placed 'inflatable dolls' in the passenger seat, a practice that persists today even though it is now illegal. Cameras that can distinguish between humans and mannequins/dolls were tested in the United Kingdom in 2005.

In the United States, a number of methods have used by drivers in attempts to circumvent HOV occupancy rules:
 * Placing store mannequins, blow-up dolls, kickboxing dummies or cardboard cut-outs in the passenger seat;
 * Taping styrofoam wig stands with wigs or ballons with faces drawn on them to the passenger seat headrest;
 * Buckling the passenger-side seat belt and pretending to talk to someone reclining in that seat;
 * Covering an empty infant seat with a blanket and/or placing a doll in it;
 * Strapping dogs, cats or other pets into the passenger seat.

In January 2013, a motorist tried to claim that the Articles of Incorporation of his business – which had been placed unbuckled on the driver’s seat, constituted a person, citing the principle of corporate personhood and California's state Vehicle Code, which defines a person as “natural persons and corporations.” This argument was subsequently rejected in Traffic court, which commented that "Common sense says carrying a sheath of papers in the front seat does not relieve traffic congestion."

In February 2010, a 61-year-old woman tried to pass off a life-size mannequin as a passenger in order to use the HOV lane in New York State. A police officer on a routine HOV patrol immediately became suspicious when he noticed that the so-called passenger was wearing sunglasses and using the visor on a cloudy morning. When the Deputy Sheriff approached the vehicle, he discovered that the passenger was in fact a mannequin wearing lipstick, designer shades, a full length wig and a blue sweater. The driver was issued a traffic ticket, for using the HOV lane without a human passenger, which carries a fine of $135 and two points on a driver's license.

In early 2006, an Arizona woman asserted that she had been improperly ticketed for using the HOV lane because the unborn child she was carrying in her womb justified her use of the lane, while noting that Arizona traffic laws don't define what a person is. However, a judge subsequently ruled that to qualify as an "individual" under Arizona traffic laws, the individual must occupy a "separate and distinct" space in a vehicle. Likewise, in California, in order to utilize HOV lanes, there must be two (or, if posted, three) separate individuals occupying seats in a vehicle, and an unborn child does not count towards this requirement.

In 2009 and 2010 it was found that non-compliance rates on HOV lanes in Brisbane were approaching 90 percent. Enhanced enforcement led to increased compliance, average bus journeys times dropped by up to 19 percent and total person throughput increased by 12 percent. In 2006 it was claimed that many vehicles had only one occupant.

Effectiveness
According to 2009 data from the U.S. Census 76% drive to work alone and only 10% rideshare; for suburban commuters working in a city the solo-driving rate is 82%.

Some underutilized HOV lanes in several states have been converted to high occupancy toll lanes (HOT), which offer solo drivers access to HOV lanes after paying a toll.

HOV lanes are also an effective way to manage traffic after natural disasters as seen in New York City after the October 2012 storm Hurricane Sandy. At the time Mayor Bloomberg banned passenger cars entering Manhattan with less than three occupants. The restrictions impacted all bridges and tunnels entering the city except on the George Washington Bridge.

Criticism
Critics have argued that HOV lanes are underutilized. It is unclear whether HOV lanes are sufficiently utilized to compensate for delays in the other mixed-use lanes.

Incidents
In 1995, six people died in a head-on collision when the gates of a reversible lane were not set correctly on the Interstate 279 in Pittsburgh, Pennsylvania.