A transit mall is a street, or a set of streets, in a city or town that is reserved mainly for pedestrians and public transit vehicles. Automobile and truck use is prohibited or greatly restricted during all or most of the day but delivery vehicles are usually permitted at certain times. Bicycles and other non-powered vehicles may also be allowed.
Transit malls offer important advantages as compared with the alternatives for routing light rail, tram or other transit vehicles through high density commercial areas. As compared with operating on conventional streets in mixed traffic with automobiles and other road vehicles, transit vehicles operating in transit malls eliminate the common problem of delays due to traffic congestion, reduce local air pollution, and can make walking a healthier, safer and more pleasant experience. Recent studies have shown that air pollution from road vehicles can be even more harmful to human health than previously thought, and it might be a long time before there is a mass conversion from internal combustion engine vehicles to electric vehicles, largely because of growing consumer resistance.
Moreover, transit malls can be created at far lower cost, much more quickly, with much less carbon dioxide emission (from construction equipment and producing concrete), and often with much less disruption of existing businesses, than building a subway or elevated route. They can also be much more convenient for transit users, and especially for handicapped and elderly users, because there is no need to go up and down stairs, escalators and elevators. Moreover, they can simplify transfers between multiple lines that converge on the tracks or roadway running through the mall.
Transit malls have become increasingly popular in city centers, mainly in Europe, in recent decades, and are often created as an integral part of the many new light rail systems that are being built there.
Although some transit malls have also been built in the United States, many of them have not been successful and have been restored to ordinary streets. One major reason is a "lack of visibility," with a consequent loss of sales, for some businesses which depend heavily on being noticed by people in passing automobiles. Another is that at off-peak times, particularly at night, such streets can feel "deserted" and thus unsafe for pedestrians, who tend to avoid the area and contribute further to retail losses.
This contrast with the European experience has been attributed in large part to the fact that the U.S. has long been much more dependent on automobiles than Europe. Also, Americans are generally more reluctant to use transit than Europeans, especially higher income people. The difference is also a result of the fact that the transit in transit malls in the U.S. is often inferior to that of Europe in terms of destinations served, speed, frequency and mode. That is, the new European transit malls are generally served by light rail that can provide a speedy and comfortable service stretching out into the suburbs whereas the transit in malls in the U.S. consists mostly of buses, which get caught in traffic outside of the transit malls and usually do not provide an attractive alternative to private automobile use.
Foremost among the requirements for the success of a transit mall is the provision of a high quality of transit service: i.e., one that is swift, comfortable, inexpensive, frequent and has useful destinations. Merely routing local bus lines through the mall, as was often done in the U.S., is usually not sufficient. Rather the transit lines, ideally light rail or tram, should operate on exclusive rights of way (e.g., strips of land in the centers of or parallel to roads) outside of the city centers rather than sharing streets with automobiles and other road vehicles.1
Also of great importance is to make the transit mall an attractive destination. This includes providing a high degree of safety, a variety of shopping and other activities and services, cleanliness, and a variety of amenities, such as restrooms, trees, benches, public art, and shaded locations to protect people from sunlight, rain, etc.
Transit malls can help protect the environment in several ways. One is the reduction in energy use and greenhouse gas emissions from constructing rail lines through city centers on the surface as compared with underground or on elevated structures.
A second is that by greatly reducing transit system construction costs in city centers, more funds can be available for expanding systems to serve additional areas within cities and also to construct systems in more cities. A third is reduced air pollution created by urban residents by providing a more attractive alternative to automobile use for some trips.
A fourth is providing a better alternative to living in distant suburbs by making city centers and their nearby surroundings more convenient and attractive places to live, work and shop. More people in higher density areas rather than in highly automobile-dependent distant suburbs can help reduce sprawl, with its destructive effect on habitats and agricultural lands and its high greenhouse gas emissions per capita.
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1 There are exceptions, particularly for streets or areas which are already high density and thriving. One is Yonsei-ro in Seoul, South Korea, which was already serviced by a heavily used subway line and multiple bus lines at one end as well as several bus lines running on it. See https://seoulsolution.kr/ en/content/ development-program-yonsei-ro-transit-mall