Transportation Deployment Casebook/2021/Idaho Streetcar

Quantitative AnalysisEdit

Streetcars in the United States and IdahoEdit

Streetcars are a mode of transport that are set apart from other modes as they travel on rail with a dedicated right of way (Britannica, 2018). They have been fueled by many different methods; first by horses; then by cables running between a slot in the road; and then, with technological advancement, by electric poles connected to overhead wires. Its progress through the different methods bought about major social, economic and commercial changes and development. It is important to note that streetcars and light rails have significant differences between them, despite them being commonly interchanged. An important technological characteristic of the streetcar is the trolley pole connected to overhead wires, which also brought about its uniqueness. It drew electricity from the connected wires above it and provided electrical power to the traction motors to operate (Dell et al., 2014). There is a myriad of advantages to the streetcar, with some of the major benefits being the longer distances they could travel and their lower fare/operating costs, of which both have direct impacts on the citizens. The horse car, which was the mode of transport prior to the electric streetcars, had operated at a much higher cost due to the costs of feeding and catering of the horses (Cameron, 2017). Moreover, due to them being animal driven, they were limited to the distances they could travel to and speeds they could travel at. The cable cars that were propelled by steam engines also had disadvantages with regards to its method of operation. It released a lot of pollution into the atmosphere and had constantly malfunctioned, jamming the street rail tracks (Britannica, 2018). The electrification streetcars were by far a more efficient, cheaper and greener alternative compared to other modes. Their main markets were the commuters that needed o travel to work. A great number of citizens did not live near their workplaces and lived-in communities and towns further away. Due to the lower cost of the fares, the streetcars were hence available to most working-class citizens and exposed them to more job opportunities (Boise State University, 2021). Another of their markets was tourism; The Natatorium, a touristic hot spot, saw a significant increase of tourists when streetcars started operating (Boise State University, 2021).

History of StreetcarsEdit

The history of streetcars in the US dates back to the early 19th century with the introduction of omnibuses (horse buses). Omnibuses were a type of carriage that had two axles and four wheels and was usually drawn by 2 horses (Charleston County Public Library, 2017). They followed predetermined schedules and travelled along pre-determined routes. Before omnibuses existed, passengers would walk to places by foot, and were hence limited by their physical stamina. The invention of omnibuses spared passengers fatigue and allowed them to carry cargo from one place to another. Unlike the rest of the inventions, omnibuses were not a result of technological innovation, rather they were a result of the evolvement of existing offerings (Charleston County Public Library, 2017). As new street rails and railways started developing, streetcars driven by horses became a smoother and faster alternative. Due to the growth of railways and track laying, horsecars could now operate on specific routes without interfering with other traffic. However, animal-powered transport had a lot of issues: they needed a great amount of care which required significant effort (Cameron, 2017), their manure polluted the streets (Morris, 2007), and they had a high operating cost (which meant they were out of reach for working class individuals). In 1873, a source claims that Andrew Hallidie witnessed the torture of horses while they struggled to pull carriages in areas with steep topographies and wet cobblestones, which mainly prompted the innovation of his steam engine-powered system. The rail system was cable driven and constituted of long cables that went through slots and passed over steam shafts located in powerhouses (Britannica, 2018). One of the major disadvantages of cable cars was that they all travelled at a constant speed, hence any malfunction that occurred resulted in shutting down the entire route Furthermore, as demand for cable cars increased, more construction of powerhouses was needed. This required a lot of investment from the government and communities and was not financially feasible (San Francisco Municipal Transportation Agency, n.d.). Despite no evidence that cable cars were used in Idaho, the limitations of cable cars prompted the invention of electric streetcars in 1888, and a streetcar system then opened shortly in Idaho in 1891 (Casner, 2002). It is important to note that in 1834, Thomas Davenport had created the battery-powered electric motor which led to the electrification of streetcars (Britannica, 2018). The electric streetcars worked very similarly to the cable cars but were powered by electricity via electric poles (trolley poles) that were connected to overhead wires rather than powered by mechanical pulleys (Dell et al., 2014).

History of Streetcars in US

Invention of Streetcars and it's TechnologyEdit

As already mentioned, right before the electrification of streetcars, the public relied on steam engines and steam powered cable cars. The technological artefacts and creations of the cable car helped develop the electric streetcar. They both drew power, but from different sources and in different manners. Cables in a cable car were initially drawn by steam powers in powerhouses, but as electricity became more available, Figure 1: History of Streetcars in the United States electric motors had replaced steam powers for some locomotives. The cable car itself, however, had no engine or motor on it - unlike the streetcar, which was propelled by an onboard electric motor and drew power from a trolley pole that was connected to overheard wires. The cable car powered by the electric motor was not a popular alternative as it was a very expensive alternative. It is important to note that in 1834, when Thomas Davenport had developed the first battery-powered electric motor, he faced a lot of criticism from investors; they stated that the battery cannot hold its weight and it’s an impractical battery as it was costly (Karlsruhe Institute of Technology, N.D.). The limitation of the cable car, as well as Davenport’s battery-powered electric motor, prompted the innovation of the streetcars. Moreover, electricity was initially transmitted through the street rails, but as that was a safety risk, overhead wires were the safer alternative (Popular Mechanics, 1929).

Early Market Development, Market Niches and Functional DevelopmentEdit

Idaho was a state that relied on horsecars and horse buses right before the innovation of electrification. The market development in Idaho consisted of replacing horsecars with electric streetcars as they were seen as a “greener” alternative. The streetcar system in Boise, Idaho’s capital, started in 1890, and began operating in 1891 under the Boise Rapid Transit Company (GrizTech, N.D.). The streets cars ran on electricity harvested from a flour mill called Cyprus Jacobs, and in 1904 the Boise and Interurban Railway was introduced and powered by a dam at Swam Falls. A third streetcar company opened, the Boise Valley Railroad Company, and started operating on another route. All three ran on different tracks, but in 1912 the existing companies merged together into a company called Idaho Traction Company (GrizTech, N.D.). One of the most important niche markets in Idaho was the transportation of people from one part of the city to another. As the streetcars systems developed and started travelling along more routes, the citizens were able to travel quicker and more efficiently between places. When the companies merged as one and shared their tracks with each other, trolleys were able to “loop the loop” and connected many villages and towns with each other (GrizTech, N.D.). Hence, a major functional enhancement that was brought about by the development of streetcar companies in Idaho was that many people were now able to travel between each suburb quicker - in 30 to 90 minutes and costing them only 5 cents, especially as companies started to merge (Boise State University, N.D.). Both these advantageous features (faster travel time and lower cost) were not present in horsecars, and if they were, were only affordable by the upper class. Moreover, as streetcar companies travelled to more places and introduced more routes, citizens started settling in other areas of the city, especially in places closer to their work or their preferred suburbs (Boise State University, N.D.). This, in return, fed back into the system and increased functionality of streetcar systems and motivated companies to keep providing services more efficiently. Due to the increased demand and quality of streetcars system (that yielded economies of scale), streetcars can be referred to as a magic bullet (Levinson and Garrison, 2014).

Functional discovery was a huge factor in developing the market. Businessmen started to adopt new distribution systems to deliver goods and freight. For example, meat and fruits were now coming from the original stockyard to be regionally distributed, forming a larger and new network of distribution, and ultimately forcing streetcars to be bigger in size and travel at faster speeds to keep up (Smithsonian, N.D.). As the functionality of streetcars increased, it served a new market: tourism. One notable example in Idaho was the Natatorium mansion. The reason it was a very successful hot spring is because citizens could travel from their hometown to where its located (the Warm springs avenue) for just a nickel; they would enjoy the day and spend a day of leisure at the pool (Boise State University, N.D.

Role of Policy in Birthing PhaseEdit

In some areas in the united states, the operation of horsecars and horse trams were managed by the same companies that managed the introduction of streetcar systems into the city. In Boise city, the Boise Rapid Transit company initially managed the horsecars, and later the electrification of streetcars (Labbe, 1980). Both horse cars and electric streetcars ran on track and were run by two crew members, one collecting fares and the other operating the streetcar system. In 1890, franchise agreements, which consisted of the responsibilities and duties Figure 2: Trolley Loop running from Boise to Nampa to Caldwell and back. (Giztech, N.D.) companies are obliged to follow, were put into place. If they acted in accordance with the agreements, they would be allowed to provide their services on more than one route, giving them an opportunity to expand and plan a transport network that would enable citizens to travel from one area to another. Furthermore, they agreed on many controversial issues to secure their position as a monopoly in the state and to ensure that they pocketed all the profits of their services (Jones, 2010). They, therefore, agreed they will charge a constant fare of 5 cents and will take over the maintenance of the pavements around the tracks (Jones, 2010). As the fare was “locked” to 5 cents (a nickel), streetcar companies had made fortunes in the birthing phase of streetcar system, especially during the deflation period of the US. This caused disagreements later on with the local government as the streetcar companies did not want to renegotiate any fares. However, many franchise agreements later, the local government decided to impose policies that stated companies must provide discounts at peak hours and must operate late at night to compensate for the lack of fare renegotiation (Jones, 2010).

Growth/Mature and Decline of StreetcarsEdit

With the urbanization of cities, streetcars became the dominant mode to commute from one place to another. With their development and the streetcars businesses expanding, it enabled real-estate developers to build many towns (Cullingworth et al., 2013). They would invest in the streetcar companies and entrepreneurs in the surrounding suburbs would have the opportunity to develop the residential and commercial aspect of the city. Land speculators specifically invested in streetcars as that means they could influence companies to service their communities, and hence drive land prices up and grow their towns. It played a key role in the urbanization of the city and therefore they became attractive private enterprises for investors to invest in (Cullingworth et al., 2013). As mentioned above the public government sector was involved in agreements between what streetcar companies were allowed to do and what they weren’t allowed to do through franchise agreements. Streetcar companies agreed to a multitude of conditions set out by the government to ensure they are a monopoly in the city, and hence they saw tremendous growth in the early 1890s and 1990s. Right before world war began, as well as during the world war, the streetcar systems still increased but at a decreasing rate. To improve efficiency, as well as keep up with demand, streetcars were having 8 wheels installed rather than 4 wheels (Britannica, 2018). They also had wooden bodies of the cars being replaced with steel bodies, which included the replacement of open doors with enclosed doors (Britannica, 2018). Despite all these design changes, the streetcar faced huge constrains in 1920. The locked in fare was not able to match inflation and the other transport modes were competing (busses and automobiles). Streetcar services in small cities were being replaced with buses, especially if they were infrequent and did not carry huge load. Streetcars in that situation had much higher depreciation and interest costs per passenger compared to a bus that is carrying a heavier load that’s frequently serviced, and hence buses were much more cost effective (Slater, 1997). Other reasons why passengers opted for busses rather than streetcars include comfortability and faster travel times (Slater, 1997).

Opportunities to Re-Invent the ModelEdit

In modern day, the streetcar system sees its alternative as the light rail system, which as mentioned above, have different characteristics to streetcars despite functioning similarly. Streetcar systems in the early 19th century was privately owned and not government-owned, despite significant influence from the government in terms of policy and operation. An opportunity to re-invent the mode is for government is to implement, and take ownership of, the streetcar systems in high density urban areas where ownership of private vehicles may be costly. This would build a larger network, create a multitude of transportation options and would provide citizens with more job opportunities (Kurtzleben, 2015).

Qualitative AnalysisEdit

The Model and ResultsEdit

As streetcars are a technological innovation, they follow a cycle of technology that consists of 4 major stages: birth, growth, maturity and decline. An S curve has been developed that best fits the data to identify the different stages of the cycle, with the assumption that the data follows a logistic shape (Garrison & Levinson, 2014). Using the McGraw Electric Manual Railway, the miles of the streetcars were recorded and are presented in Table 1 below. The Model used to calculate the status of measure (in this case the miles) is a three parameters logistic function defined as:

S(t) = K/[1+exp(-b(t-ti)]

where the technology size is proportional to the final market size and the following parameters defined as:

S(t) = status measure (length of track)

K = saturation status level b = coefficient to be estimated

t = time (in years)

t0 = inflection time (the year that half Smax is reached)

The model was transformed into a linear relationship for an easier estimate to determine the year where 50% deployment is reached, the final market size and a specific coefficient parameter. As the size of the market in any year is given, a projection of the final market size based on the curve that best fits the data can be made through iterating through various Ks using a solver type of routine. If K is known, then the inflection year can be deduced.

The model produced the following outputs:

Variable Value
k 310
b 0.310
t0 1911

Table 1

where the K value is the saturated market value (that was determined based on the regression value closest to 1), the b value is the slope of the curve, and the t0 value is the year the point of inflection occurred (point of maximum growth).

The Actual and Predicted length of the Streetcar System in Idaho from 1894-1920:

Year Length of Tracks (miles) Predicted Length of Tracks (miles)
1894 3 2.16
1897 3.50 5.41
1898 3.50 7.33
1899 3.50 9.92
1900 3.50 13.36
1901 3.50 17.94
1902 3.50 23.95
1903 5.50 31.77
1904 35.50 41.76
1905 44.00 54.28
1906 104.00 69.58
1907 124.00 87.71
1908 137.00 198.43
1909 151.00 131.17
1910 178.00 155.00
1911 81.00 178.33
1912 81.00 201.57
1913 98.00 222.29
1914 102.50 240.42
1917 284.70 278.23
1918 303.70 286.05
1919 302.20 292.06
1920 160.20 296.64
Year Miles of track Total
1894 3 3
1897 3.50 3.50
1898 3.50 3.50
1899 3.50 3.50
1900 3.50 3.50
1901 3.50 3.50
1902 3.50 3.50
1903 5.50 5.50
1904 5.50 30 35.50
1905 7 37 44.00
1906 7 37 60 104.00
1907 8 46 70 124.00
1908 9 50 73 5 137.00
1909 8 10 9 50 74 151.00
1910 135 178.00
1911 81.00
1912 81.00
1913 98.00
1914 102.50
1917 284.70
1918 303.70
1919 302.20
1920 160.20

Interpretation and AccuracyEdit

As mentioned above, this model helps in predicting the different cycle stages as it approximates an S curve. From the graph, it can be seen that the birthing stage of the model is occurring between 1894-1904. Despite the introduction of streets cars in Idaho in 1891, Idaho was a very small city with a low population density, and hence the birthing phase did not experience much growth. Moreover, there is an evident period of exponential growth from 1905 up to the inflection year (1911) which represents the growth stage of the cycle. From 1911 onwards, the growth occurred at a decreasing rate, indicating the maturity stage of the cycle. As the R-squared value of this model is 0.94 and the T-state value is larger than 2, the results can be considered statistically significant (at the 95% confidence level). However, despite the model being a good fit, it does not fully capture the reality of the situation. During the growth phase in 1905-1911, the track length fluctuated with growth declining and increasing between the years and that is not represented in the S curve. Furthermore, the data from 1895, 1896, 1915 and 1916 were not recorded and their values were assumed based on a trend, and hence any growth decline will not be depicted and will raise validity issues.


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[10] Boise State University, (N.D.). Trolley Town.

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[12] Smithsonian. (N.D.) A streetcar city.

[13] Labbe, John T. (1980). Fares, Please! Those Portland Trolley Years. Caldwell, Idaho: Caxton. ISBN 0-87004-287-4

[14] Jones, D. W. (2010). Mass motorization+ mass transit: An American history and policy analysis. Indiana University Press.

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[16] Slater, C. (1997). General motors and the demise of streetcars. Transportation Quarterly, 51, 45-66.

[17] Kurtzleben, D. (2015). Everything you need to know about the streetcar craze. [20] "This is how some of the world's familiar..." Archived 1 January 2016 at the Wayback Machine Popular Mechanics, May 1929, pg. 750. via Google Books.