Light rail in North America
They became popular because roads were then poorly surfaced, and before the invention of the internal combustion engine and the advent of motor-buses, they were the only practical means of public transport around cities.
When lines were built over longer distances (typically with a single track) before good roads were common, they were generally called interurban streetcars or radial railways in North America.
After World War II, seven major North American cities (Boston, Newark, New Orleans, Philadelphia, Pittsburgh, San Francisco, and Toronto) continued to operate large streetcar systems.
Cleveland, Ohio, maintained an interurban system (e.g. the Blue and Green Lines) that is equivalent to what is now "light rail", which opened before World War I, and which is still in operation to this day.
Using standard gauge also allows light rail vehicles to be delivered and relocated conveniently using freight railways and locomotives.
Additionally, more manufacturers are able to produce standard gauge vehicles, reducing costs for rolling stock acquisition.
Diesel operations are chosen in corridors where lower ridership is expected (and thus do not justify the expense of the electric power infrastructure) or which have an "interurban" nature with stations spaced relatively far apart (electric power provides greater acceleration, making it essential for operations with closely spaced stations).
[23][24] This means that transportation planners must allow for higher passenger volumes on Canadian transit systems than American ones.
As a result of lower government funding, Canadian cities have to recover a much higher share of their costs out of operating revenues.
[25] In late 2015, Calgary Transit started running four-car trains to alleviate congestion as the system exceed 300,000 passengers per weekday.
[27][28] The route (today called the Capital Line) first started construction in 1974, and opened its first segment on April 22, 1978, in time for the 1978 Commonwealth Games.
The separate Valley Line, under construction as of 2024[update], but with its first 13.1-kilometre (8.1 mi) phase opened in November 2023, uses low-floor vehicles.
In 2001, to supplement its bus rapid transit (BRT) system, Ottawa opened a diesel light rail pilot project, the O-Train, which was relatively inexpensive to construct (CA$21 million), due to its single-track route along a little used freight-rail right of way and use of diesel multiple units (DMUs) to avoid the cost of building overhead lines along the tracks.
Cleveland and Philadelphia have light rail systems originally built as interurban railroads that only received maintenance and rolling stock improvements while offering nearly the same services since their inceptions.
Additionally, Philadelphia's system of subway–surface streetcar lines, which utilize a tunnel in the downtown area, were largely established in their current configuration by 1956.
By World War II, most of San Francisco's streetcar routes had been converted to buses, but some lines still utilized exclusive right of ways.
The upper level of the newly constructed Market Street subway, originally intended to carry several lines of the Bay Area Rapid Transit system, was given to the San Francisco Municipal Railway to establish the Muni Metro.
Simultaneously, PCC cars were replaced with modern light rail vehicles, service rerouted from the surface, and several stations were upgraded to include high-level platforms.
Total rerouting took place in 1982, however large parts of the network still feature street running sections and varying degrees of traffic separation.
San Diego built what is considered the first newly constructed light rail system in the United States which was opened in 1981.
Light rail was chosen for several reasons, including its ability to travel at high speed for long distances, power cost compared to full heavy rail rapid transit, ability to utilize at-grade construction, minimizing of operating deficit, and expediency of construction.
Some cities have established heritage streetcar operations to preserve equipment and infrastructure in addition to offering transit services.
