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High Speed Trolleys - 2
A Practical Solution for Today's Traffic Problems
By: Bob Morrisson
Some Transit Solutions
The leaders of a number of cities have begun to realize that automobiles and busses are not terribly efficient for moving people. A number of solutions are available, not all of which are practical in all situations.
Heavy Rail / Subway
Heavy rail (which includes subways and other high volume trains) can move large numbers of people effectively. There must be sufficient traffic to warrant the extremely high costs for building and maintaining the system. Construction can be disruptive for many years, however, neighborhoods served by the trains generally prosper afterwards.
A heavy rail system should be isolated from other modes of transportation and from the public. Grade separation, fenced rights of way, and tunnels are all expensive. Stations generally have high level platforms and thus require stairs, escalators, elevators, and ramps for people to move between locations. Each station requires fare collection equipment, which ranges from a simple honor system to complex and expensive stored-value farecard system.
The trains operate at high speeds, often in tunnels with curves and grades, so an efficient signaling system is a necessity. Many systems now use automatic train control (ATC), which is expensive to build and maintain. ATC allows trains to operate closer together than when operated manually and the ride can be smoother since the automated system can anticipate to a degree what is happening up ahead.
Heavy rail can be cost-effective when it carries large numbers of people. It is an effective system for moving people between major population centers, to places of employment, or to large public facilities such as airports and stadiums.
Busway and HOV
Highways can be modified with reserved lanes and ramps for busses and high occupancy vehicles (HOV). In some implementations busses operate in rapid transit fashion, with station platforms and frequent service. Busways add to the complexity and expense of the highway but it is far less expensive than building a subway line. Buses burn fossil fuels (diesel, natural gas) and there can be operational problems in icy weather.
Bus rapid transit (BRT), which use specialized vehicles, has been tried in a number of cities with mixed results. BRT is often touted as being just like a trolley but on rubber tires and with lower start-up costs, since there are no rails. Some BRT systems use a fixed guideway system, which has proven expensive to build and difficult to maintain. There is usually little discussion about the cost of obtaining new, custom-designed vehicles in the next 15 years.
Dedicated highway lanes, dubbed High Occupancy Vehicle (HOV) lanes, are inefficient unless people can be convinced to use them. They do encourage car pooling and ride sharing, however, they are often under-utilized and they are also despised by some motorists. Some cities have considered putting in High Occupancy Toll (HOT) lanes. Critics have dubbed these "Lexus Lanes" because they encourage the wealthy to drive while the less fortunate must car pool or take the bus.
For older highways that cannot be widened a "Zipper" can relocate one or more lanes for rush hour travel. This clever machine picks up the "Jersey Wall" and relocates it, thus creating an extra lane for the side of the highway with the most traffic.
Surely you jest! New roads can help postpone the inevitable but new road construction is proving increasingly unpopular. Environmental issues and lawsuits from activists may turn the road into a political football, bouncing around aimlessly for years or decades and never being built. Along the way some politicians may be re-elected or ousted from office for their part in handling, or mis-handling, the project.
A classic example of this problem is the Inter-County Connector (ICC) to be built outside Washington DC. This 18 mile toll road will provide an east-west connection between two Interstate highways, thus reducing traffic on a number of traffic-choked local roads and the Beltway. It is quite likely that once this road is opened, commuters seeing the side roads less congested will rush to fill the spaces vacated by those using the ICC.
The $2+ Billion ICC has been over 40 years in the making, with environmental groups, nimbys ("not in my back yard!"), and politicians challenging each other at every turn. For the same $2 Billion you can extend the Metro subway much of the way to Dulles Airport or all the way to Baltimore-Washington International Airport.
If you really like new highways please visit Atlanta, Dallas, or Los Angeles to see if your reality check has bounced. Cars have all but choked these cities and the super-wide highways and massive interchanges are a blight. In the short run traffic jams are an annoyance. In the long run people choose their jobs and homes based on the highways, if they don't move out of town first.
Monorails have a certain allure. They are compact, they can operate in the middle of a street or in the middle of building, and they look quite futuristic. They have also never proven to be the panacea their promoters have claimed them to be.
The complex parts of the monorail structure are mostly hidden from view. The cars often ride on a rubber tired truck, which rolls on a concrete rail. Guideways keep the wheels on the track. While such incidents are rare, it is possible for a truck to derail or for a wheel to fall off.
The monorail structure is technically challenging. Since there are no steel rails, a series of conductor bars is used for power and signaling. For an automated monorail there could be a fair number of conductor bars, each touched by a sliding shoe on the train.
Switching trains between tracks is challenging. Typically, a large section of the structure must be moved to route the train onto the proper track. Thus, it is advantageous to keep trains on a single route, without a lot of divergences.
Monorails are slim and trim, and so is the space inside them. Trains run with a limited carrying capacity and at moderate speeds so you are not going to move a lot of people with them. Monorails do very well in areas with a controlled environment, such as an amusement park or an airport. But in a city where travel patterns are not always predictable, a complex monorail system would likely be a big bust.
Light Rail / Trolley
Trolleys, also called Light Rail or Streetcars, offer many of the advantages of heavy rail without the disadvantages. Construction is simpler than for a heavy rail line. Declining neighborhoods often come back to life after a trolley has started running nearby.
Trolleys are usually powered from an overhead wire and thus they can share space with people and with other modes of transit. Grade crossings can be tolerated, eliminating the expense of overpasses and tunnels. Trolleys can pre-empt the traffic signals. Trolleys can climb steeper grades than heavy rail trains. Modern trolleys are generally articulated, meaning that have multiple sections that allow them to bend around sharp turns. They can also be coupled into trains.
Trolley stations can be built next to the track at curb level. Passengers can be permitted to cross the tracks, eliminating the need for escalators, elevators, and ramps. Fare collection can be very simple, consisting of a few ticket vendors and ticket validators at each station. Inspectors make spot checks for fare cheaters. Trolley lines generally operate line-of-sight and don't require a complex signal system.
Trolleys can be effective in areas where traffic does not warrant heavy rail or where such construction is not possible. The lines are less expensive to build than heavy rail since they can be built to a more relaxed standard.
A number of interesting systems have been developed but none have proven to be practical on a large scale. These include magnetic levitation (MagLev), which consumes vast amounts of power; monorails (see above); rubber tired trains, which are slow and complex to operate; and cable powered trains.
Many of these systems work well in a controlled environment such as an airport or an amusement park but they are not very practical for moving large numbers of people through a city. There are some exceptions. The people mover at Morgantown, WV is still running after some 30 years. The monorails in Seattle Washington in the US and Wuppertal in Germany have been running for many decades. The rubber-tired people mover at the Dallas Fort Worth airport has been less than successful and it is being replaced.
In Fort Worth Texas Leonard's Department Store built a private subway to carry passengers from their parking lot to their store. Surplus trolleys from Washington, DC operated through a tunnel built from quonset huts. The system was later bought by Tandy and upgraded with "new" cars built with parts from retired trolleys and elevated trains. The line closed on August 30, 2002 after more than forty years of faithful and cost-effective service.
The Interurban Revival
One of the more promising solutions for our traffic woes is the high speed trolley (or light rail vehicle, if you prefer), which is a modern version of the interurban trolley. Whatever you call it the concept is good, it is cost-effective, and it works:
Older trolleys had a few practical problems, which have been addressed in modern systems.
If you haven't ridden a modern trolley you are in for a pleasant surprise. In the next section we'll visit Portland, Oregon, which has two systems, the high speed inter-city Max trains and the local Portland Streetcar.