Q: What is rail transit?

A: Rail transit is passenger transportation over relatively short distances and in urban or suburban areas using vehicles that have steel wheels and run on steel rails. It includes both light rail and heavy rail.

Q: What is the difference between light rail and heavy rail?

A: Heavy rail includes conventional subway and elevated systems and commuter rail lines. Light rail uses smaller and lighter weight vehicles than heavy rail. It is also more flexible, in that it is capable of running in streets and in transit malls in addition to its own right of way, and it can usually accommodate sharper curves and steeper grades. It is also typically much cheaper to construct and operate than conventional subway and elevated lines.

Q: What is commuter rail?

A: Commuter rail a type of heavy rail transit that mostly or entirely uses existing freight and passenger train tracks and is designed primarily for commuters. The frequency of service is typically much less than for light rail, but the cost of starting it is generally far lower because of the minimal amount of construction required and because it is usually not necessary to electrify the line. An example of commuter rail is Sound Transit's Sounder locomotive-hauled trains currently being operated between Seattle and Tacoma and between Seattle and Everett. Eastside Rail Now! is advocating that the Eastside railroad initially be used for commuter rail.

Q: What is the difference between streetcars and light rail?

A: They use very similar technologies. A major difference is that light rail lines usually utilize mainly private rights of way (i.e., on the ground, in tunnels and on elevated structures) whereas streetcars usually operate mostly or entirely on tracks laid in the streets. This is one reason that light rail generally provides faster speeds than streetcars; other reasons are that the stops are typically spaced farther apart and the vehicles are designed for higher speeds. In addition, light rail vehicles are usually larger and have greater passenger capacities. However, the differences are not always clear, as some streetcar lines have light rail-like characteristics and some light rail lines run on streetcar tracks for part of their routes.

Q: What is DMU?

A: DMU (diesel multiple unit) is a type of rail passenger vehicle that is powered by a self-contained diesel engine and do not need to be hauled by locomotives. DMUs provide many of the advantages of electrically powered light rail vehicles but do not require the expense and time needed to erect overhead electrical wires. They are well suited for use on existing railroad lines, including those for which a pilot transit service is being launched. After traffic volume reaches a certain level it usually becomes more economical to electrify the railroad. DMUs are in widespread use abroad and are also becoming more popular in the U.S. For more about DMU, please visit the page Diesel Multiple Unit.

Q: Isn't rail transit an old-fashioned technology?

A: No. In fact, it is no older than the first busses (which were pulled by horses) or even the first automobiles. Moreover, rail technology has continued to advance rapidly in recent years. For more about recent progress in rail transit technology, please visit the pages Advances in Light Rail Technology and Diesel Multiple Unit.

Q: Is monorail a kind of rail transit?

A: Most monorail systems do not actually use rails, despite their name. Rather, they have rubber tires and run on a concrete beam. Thus, they resemble a guided bus more than rail transit. A more appropriate name might be monobeam.

Q: Wouldn't it be better to build monorails than rail transit, because they are cheaper, more modern and can run above all the traffic and other obstacles?

A: It is not true that monorails are cheaper than rail transit. Typically, they are much more expensive because costly elevated structures need to be constructed, whereas rail systems can use existing tracks and rights of way and can even run in streets and transit malls. Monorails have a number of other disadvantages as well, including cumbersome switches and a lack of routing flexibility. Moreover, monorails are not particularly new; the first one was built more than a century ago.

Q: Wouldn't it be cheaper to just improve bus service?

A: Busses have a lot of disadvantages. For example, they tend to be slow and get stuck in traffic. Also, the operating cost per passenger can be substantially higher than that of rail transit, particularly where there are large passenger volumes. Busses also require more energy and create much more pollution per passenger than rail systems. In addition, most people do not like to ride busses for a variety of reasons; in contrast, rail transit is quite popular and new systems invariable attract not only former bus riders but also substantial numbers of people who previously drove.

Q: What is "fixed rail?"

A: This is a term that is used mainly by opponents of rail transit. It is meant to imply that rail transit is somehow inflexible. It is misleading because rail is not "fixed" to any greater extent than freeways are fixed. In fact, it much less expensive, faster and far less disruptive to build a new rail line to some area than it is to build a new freeway. Rail systems are also far more flexible than monorails, which tend to be more costly to build and are limited in operational flexibility because of their cumbersome beam switches, etc.

Q: Is it true that most new rail transit systems are failures?

A: No, this is a myth. Actually, the opposite has been the case; most new systems have been huge successes, even in regions that are dominated by automobile transportation. For example, the new light rail system in Salt Lake City carries close to 60,000 people a day, far higher than original projections. The new Red Line subway line in Los Angeles carries more than 140,000 passengers on the average weekday. For more misconceptions about rail transit, please visit the page Rail Transit Myths -- And Realities.

Q: What is the reason for the recent surge in construction of rail transit systems?

A: The past several decades have seen a surge in the construction of rail transit systems in the U.S., particularly in light rail and commuter rail systems, and in much of the rest of the world as well. This is a result of several factors, including rising fuel prices, growing concern about air pollution, realization that busses are not a good solution for heavily trafficked routes and advances in rail transit technology. This surge is readily apparent from looking at a list of rail transit systems and their opening dates, such as Rail Transit Systems in the U.S.

Q: Will this rapid pace of construction of rail transit systems continue?

A: Yes, and it may even accelerate. This could result from a number of factors, including (1) continually rising fuel prices, (2) increasing concern about dependence on unstable foreign sources for energy, (3) growing awareness of the adverse health effects of air pollution from automobiles, (4) mounting concern about climate change, (5) continuing advances in rail transit technology (6) and the growing acceptance, and even welcoming, of rail transit by the public and politicians because of the great success of recent new systems and thus the desire to extend them and build similar systems elsewhere.