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HOV LANE/LIGHT RAIL COMPARISON

(HIGH OCCUPANCY VEHICLE LANES)

An HOV lane is a lane, or lanes, dedicated to the exclusive use of buses, vanpools and carpools. The number of people required in a carpool varies with the volume of traffic in the lane(s). The theory behind HOV lanes is that people will chose to carpool or use vanpools or buses because they will get to their destination much faster than the people driving alone in the general purpose lane.

Surveys consistently indicate that the most important factor which determines the choice of method of getting to work or to most nonsocial, nonshopping destinations is speed. There is little incentive to carpool or use transit when the travel time is the same as using a car which offers the other benefits such as greater scheduling flexibility.

HOV lanes have a proven record of reducing the number of single occupant vehicles (SOV's). What most people do not realize is just how effective HOV lanes have been.

Portland had an HOV lane on the Banfield Freeway (I-84) from 1976 until MAX construction affected the freeway operations. MAX runs alongside this freeway.

Even the poorly designed HOV lanes on the Banfield freeway were a success. This is what ODOT reported after a three year study of the Portland HOV experience:

"Overall, the HOV lane operation can be considered a success from a traffic impact standpoint as it has reduced arterial street travel, improved peak hour operating conditions on the freeway, conserved fuel, reduced travel costs to the public and increased freeway capacity." (Oregon Department of Transportation, Banfield HOV Lane Project, August 1977)

During the time of this ODOT study, the Banfield HOV lane was limited to carpools of 3 or more riders. In 1979, the requirement was dropped to carpools of 2 or more and the results were even better than described above in the ODOT report.

As shown below, Banfield vehicle traffic counts rose just 1.85% for the six full years of HOV operations. Since the opening of MAX, average daily traffic rose over 57%, an increase of 58,953 cars per day.

BANFIELD TRAFFIC COUNTS

YEAR        AV. DAILY     % INC OR     % INCREASE     % INCREASE

                    TRAFFIC            DEC              FOR HOV           FOR MAX

                                                                      YEARS                YEARS

1977             101,424

1978             104,058              2.60%

1979             103,491              -0.54%

1980             101,603              -1.82%

1981             102,951              1.33%

1982             103,301              0.34%              1.85%

1983             NO COUNTS BECAUSE

1984             OF LIGHT RAIL

1985              CONSTRUCTION

1986             117,928              14.16%

1987             130,484              10.65%

1988             130,004              0.37%

1989             139,612              7.39%

1990             141,365              1.26%

1991             146,702              3.78%

1992             151,708              3.41%

1993             157,143              3.58%

1994             161,492              2.77%

1995             162,254              0.47%                                                  

1996             169,975              4.76%

1997             172,721               1.62%                                                 67.2%   

HOV lane operated for full years from 1977 until MAX construction.

Source: Oregon Dept of Transportation for traffic counts.

Counts made on I-84, .12 miles East of Lloyd Center Exit.

These favorable HOV lane results in Portland were obtained despite the fact that the HOV lane was never designed properly. It was too short, less than two miles in the eastbound direction and only one mile in the westbound direction. By comparison, the El Monte Busway is 11 miles long and the first section of the Shirley Highway HOV lanes is 12 miles long. Length is very important. The longer the length over which you can go at an increased speed, the greater the advantage over the general purpose lane and, therefore, the greater incentive for people to carpool and use buses.

The Portland HOV lane had no separate entrance and exit. It had no physical separation from the general purpose lanes. There was no room for policing since there were no shoulders on the freeway. Despite its many drawbacks, ODOT concluded and the effects on the Banfield traffic clearly show that it provided significant benefits

The Banfield was a two lane freeway with wide shoulders before the HOV lanes were installed in 1976. The shoulders were eliminated and the freeway was restriped. The only cost was striping the existing highway to make three lanes where there had been two. Tri Met has published statements saying that Banfield freeway traffic volume is higher because the freeway lanes were increased from two to three lanes when MAX began operating. That is not true.

An example of a much better designed HOV lane is the El Monte Busway in Los Angeles. Normally, the term "busway" is reserved for lanes restricted to the use of only buses. The El Monte Busway began as a busway. After two years of operation, carpools were added to the restricted lane. As the following table shows, the number of peak hour passengers in the HOV lane is 5.7 times greater than the general purpose lane. In another report, "MAX Versus Freeway Effectiveness," the reader will learn that just one Banfield general purpose lane carries 1.8 times more passengers than the MAX line alongside it during MAX's peak hour, peak direction. This indicates that a good HOV lane can carry 10 times the number of passengers as Portland's MAX at MAX's peak time and peak location.

The "Slug" system - The Shirley Highway HOV lanes run 12 miles from Springfield, Virginia to Washington, D.C. Two lanes operate in one direction and, then, reverse to provide two lanes in the opposite direction. A study reported by the Texas Transportation Institute (Research Report 925-4, "High Occupancy Vehicle Project Case Studies) showed that by 1985, the difference in travel time between the HOV lanes and the general purpose lanes was almost 25 minutes.

After the HOV lanes became available, bus ridership increased 445%.

The area served is low density. To expedite carpooling, parking facilities were provided next to the entry ramps to the HOV lanes, which are separated from the general purpose lanes by barriers. Drivers, who want to use the HOV lanes but have no neighbors leaving at the same time or going to close destinations, can stop at these lots and pick up passengers who parked at the provided lots. Three or more in a car are required to use the HOV lanes. These passengers are called "slugs." They ride free. The only rule is that the driver gets to pick the radio station. The system has worked successfully for many years. It is a great convenience for area visitors who rent cars and want to use the HOV lanes.

For the afternoon, homeward-bound commute, there are designated locations, like bus stops, for the "slugs" in the District and at the Pentagon area.

During the peak hour, the 2 HOV lanes carry more passengers than the 4 general purpose lanes.

A comparison of the ridership and costs of HOV lanes and Portland's light rail follows:

HOT LANES are lanes where SOV'S pay tolls while buses, carpools and vanpools drive at no cost.