Transportation Deployment Casebook/2023/Melbourne

Overview and Technology
Streetcars are an early form of rail transportation which fundamentally involve the movement of people and goods along tracks laid on the street. A streetcar is usually comprised of a single carriage or car, although sometimes more. Modern day street cars use an electric motor powered by overhead wires, or a ground-level power supply which charges super-capacitors, however the earliest models were pulled by horse. Steam engines were also trialled in streetcars, and cable powered trams had a short era of popularity in the late 19th century, mainly due to their ability to overcome steep gradients. Modern trams have wheels which run along grooved tracks, sunken flush into the road surface and are almost exclusively located in cities.

Trams were one of the first modes of rapid mass transit, able to move large groups of people at regular frequent time intervals. This made them especially suited for linking inner city suburbs and connecting commuters to the central business district. Experimentation involving electric railways began with Thomas Davenport in 1835 around the same time steam trains were beginning to take off. Most of the first electric locomotives failed due to a lack of power which can be attributed to inefficient motors and heavy loads. Davenports motor included a small motor with a stator and rotor windings, powered by an electrochemical battery. The first full-sized locomotive was designed by Robert Davidson in 1837, and utilised a two-electromagnet stator and a three-salient pole rotor. Batteries were an issue with the initial development of streetcars, being bulky and non-reusable. Innovation of new electric motor technologies was required to prove the feasibility of electric streetcars, and that came in the form of electromechanical DC generators. Batteries were replaced with cheaper energy sources such as coal, and the reversibility principle heralded by Warner Siemens in 1867 allowed for the development of much more efficient electric motors.

Siemens also experimented with overhead bipolar wires, using them to power his track-less car, the Electromote in 1882 and soon-after a tramline near Berlin. Alternatively, a third rail could be placed on the ground between the other two to provide electricity, as in the case of the Giants Causeway Tramway in Northern Island. This tramway experimented with a high voltage between 290-360V which was reduced after electrocuting a cyclist. Voltage capacity needed to be increased to improve the capabilities of streetcars, however accidents like this ultimately highlight the need for safety policies such as the Rail Safety Act 2006 present in Victoria.

The ideal power source for electric streetcars was unclear throughout the 19th century. Batteries were tested in Paris for aesthetic reasons, and In Australia battery powered trams were trialled in Bendigo, but all proved unsuccessful. In 1884, an overhead catenary was developed and tested by J.C Henry allowing streetcars to operate at a higher voltage, and a year later Van Depoele invented a spring-loaded trolley pole to provide a firm connection to overhead wires in order to collect current. Innovations of motors with fixed brushes improved safety and efficiency, and the development of the Bow current collecter improved electrical contact with overhead wires. Ground-level power systems came later, and are used in many tram systems today around the world including the Sydney Light Rail.

They were more accessible than horse drawn carriages and also cheaper and less intrusive than heavy rail. and can easily be deployed to reach many areas. They also emit less emissions than buses and can hold more people. Historically, mainly used in cities or for steep hills.

Melbourne Prior to Trams
Prior to trams, the predominant modes of transportation in Melbourne included walking, horse drawn carriages and carriages and boats. The city is situated on the Yarra River adjacent to Port Phillip Bay, however with next to no canal network and the cost and processes involved in planning, constructing, procuring and operating heavy rail lines, an alternative mode of mass transportation to horse drawn carts was necessary. This was especially true because, similar to many other major cities at the time, population and industry was experiencing massive growth as a product of the industrial revolution. Road networks and tolls were established as early as the 1840’s, servicing docks in Port Melbourne just south of the central business district and along the Yarra river, however the rise of automobile transport was still a long way off at this point in history.

As steam powered trains were growing in popularity in England and the USA, Melbourne decided to introduce the technology for the first time in the mid 19th century. Trains changed the way freight was transported and trade was carried out, however constructing new lines is not a cheap or easy process as already mentioned. Despite this, the advantages of rail transport were well appreciated and there was interest in identifying other ways to achieve these benefit which led to the birth of horse drawn trams. Horse powered transports also had its limitations. These including the constant need for care required by the horses, only being able to travel if weather permitted, slightly bumpy rides with low maximum speeds and the difficulty tackling steep gradients.

Birth
What started as horse drawn streetcars in 1884 quickly progressed into a 75km network of cable cars, one of the largest in the world at the time. What made this possible was the lack of policy regarding attaining a right of way to lay tram tracks. Road owners could simply lay track wherever they desired unlike heavy rail, as there was no need to purchase land or construct transport corridors. Companies did still require government approval to construct tramlines, with acts such as the Melbourne Tramway & Omnibus Company Act which was passed in 1883 allowing the MTOC to operate cable car systems. As some lines were meant to be horse drawn, these were located on the edge of the system and the central system was cable operated. However the growing popularity of the electric trams resulted in the conversion of the cable car network into overhead wire powered trams from 1924 onwards. Cable cars were a market niche, as much of the rest of the world was rapidly converting to overhead wire or ground-supply powered trams.

The first electric tram opened in Melbourne in 1889, connecting Box Hill to Doncaster. The new Premier Thomas Bent saw he could benefit from the line and helped acquire the appropriate legislation. The 3.6km route was an initial success, but the expiry of the Union Electric Companies contract led to technical, legal and financial difficulties, ultimately shutting the tramway down in 1896, but not without its economic potential being realised.

A second attempt at establishing electric trams in Melbourne began with the opening of the St Kilda to Brighton tram in 1906 operated by Victoria Railways. This was followed by two lines opened by the North Melbourne Electric Tramway and Lighting Company between Flemington Bridge and Essendon and Saltwater River. The public was very supportive of this development. In 1919, VR opened a second line from Sandringham to Black rock.

Growth
These tramways kickstarted the industry in Melbourne, resulting the in creation of numerous individual tramway trusts who took responsibility for expanding, managing and operating Melbournes rapidly growing tram network in their respective localities. Early examples of these trusts include the Prahan & Malvern Tramway Trust, Hawthorn Tramway Trust, Melbourne Brunswick and Coburg Tramway Trust, and the Fitzroy Northcote and Preston Tramways Trust. These trusts secured acts which granted them the ability to build tramlines in their locality.

The Melbourne Metropolitan Tramway Board MMTB took over the cable car network in 1919. It was in this period that buses had started to become a popular mode of transport in other cities. However the consensus in Melbourne was that electric trams powered by overhead wires were the best way forward, hence the tram system was maintained. other factors that contributed to the growth of the electric tram network in Melbourne included the smaller rate of emissions compared to buses and cars, the wide patterned street layout of the city suburbs, the high financial risk of ripping up the network and the potential returns on investments in electric transport.

The last cable car ran until 1940, and the electric tram network grew profitably until the time of WWII, with its peak annual patronage of 294.1 million reached in 1945. The board upgraded fleet classes on multiple occasions to classes such as the W-class, to solve operational and maintenance problems.

Decline
Post WWII, many trams were replaced with buses. In Sydney, the extensive tram network which was once bigger than Melbournes, was entirely deconstructed to make way for this promising new technology. Melbournes annual tram passengers reduced steadily during this period to as low as 98.9 million in in 1980 with no tramline extensions in 20 years. Another factor influencing this decline was the increase in private automobiles. However buses never grew in popularity and the tram network remained in tact due to Union opposition against ripping it up, allowing the possibility for re-growth. .

Maturity
New Authority in the form of the MTA was formed in the early 1990’s, where a revitalisation of Melbournes public transport network was planned. Rail, bus and tram were integrated, with new technologies improving communications and reliability. Eventually, all rail was placed under one body, Public Transport Corporation (PTC) as a result of the Transport Act 1989 ,however they still faced financial and political difficulties, and it wasn’t until privatisation in 1999 when the tram network began to mature.

The network was split in two and sold to private companies, who also initially experienced financial difficulty and did not meet projected passenger growth. The government offered incentives and extra subsidies to keep the companies on board, but ultimately one pulled out. This lead to one company, Yarra Trams, taking control of the whole system in the early 2000’s. Contracts between state government and private operators meant the system was extended and modernised. More stops and rolling stock were added and patronage began to increase slowly but steadily. Around this time electronic ticketing systems were also introduced, in line with the Transport Regulations policy, with MyKi still being active today.

Public Transport Victoria (PTV) is the current statuary authority. Transport legislation including The Disability Discrimination Act has resulted in a focus on increasing accessibility to trams with the planned introduction of more low floor trams and level boarding stops. This is because studies showed that 70% of the disabled population only has access to 22% of accessible tram supply.

Today, Melbourne's tram network is the largest in the world, with over 250km of track, 24 routes and 200 million passengers per year (excluding covid impacted years). It is the second most used mode of transport in Melbourne and play's a large role in tourism. Incentives such as the free tram zone in the city draw tourists and encourage usage, and the network also plays a key role in transport to major domestic and international events such as the Australian Open, Australian Grand Prix and sporting matches at the Melbourne Park complex. Studies have found trams actually help reduce overall traffic congestion in Melbourne (despite some negative effects on traffic flow), adding to the list of benefits, and with the increasing focus on sustainability, there's a sure demand for trams in the future of Melbournes transport network.

Quantitative Analysis
All transport systems have a life cycle. This begins with the birthing stage, followed by growth, maturing and eventually decline. In this quantitative analysis, observed annual patronage data is used to determine the life-cycle stages of the Melbourne Tram network. The observed data is sourced from the Bureau of Infrastructure and Transport Research Economics (years 1900-2013) and from Victorian Government Annual Reports from 2013 to 2022.

Table 1: Observed patronage data - passengers per year in millions

S-curve Regression Model
The observed data was used to estimate a three-parameter logistic function. The function models passenger numbers and can be plotted against the observed data to determine its accuracy.

The logistic function is:

$$S(t)={Smax \over [1+\exp-b(t-t_i)]}$$

where:


 * S(t) is the status measure,  (e.g. Passenger-km traveled)
 * t is time (usually in years),
 * ti is the inflection time (year in which 1/2 Smax is achieved),
 * Smax is saturation status level, (Choose the maximum length of the streetcar system that you have recorded in the data).
 * b is a coefficient to be estimated.

Coefficient b was determined using single variable linear regression in a  model of the form:

Y = bX + c

where:

Y=ln(Passengers/(Smax-Passengers))

X=Year

Table 2: linear regression results

Complete lifespan
As illustrated by the two peaks in figure 1, the Melbourne electric tram system has undergone two growth and maturing stages in its life cycle to 2022. The first peak, represented by the orange dot at 294.1 million passengers in 1945, marked the end of the first maturing stage, the start of WWII and the beginning of the system's decline. The second peak is in 2019, the year before covid struck and the patronage declined once again. As both periods of decline were triggered by major world crisis, it can be argued that the system has never breached the growth phase. However the introduction of buses after the war contributed to the decline of tram usage in the mid-20th century, and the revitalisation in the late 20th, early 21st century exhibited much slower growth than the first growth phase in the early 20th century, plateauing out towards 2019 and showing signs of maturing.

Given the two distinct growth periods, the data was split at the year 1980, and seperate curves modelled for the years prior and after this date.

1900-1945
This period marks the rapid rise of trams in Melbourne. The birth of the system was the 1900's with the fasted period of growth occurring in 1916. The system began to mature in the 30's, reaching its peak in 1945 as seen in figure 2.

The modelled curve is a good fit, representative of actual life-cycle trends, with the exception of the outlying point in 1940. The low number of data entry points is the primary cause of this difference between the modelled and actual data plots. The RSQ value is 0.75, which could be better but is close enough to 1 given 294.1 was the maximum number of patrons the system reached, also making this the most accurate curve out of all the curves created.

1900-1980
Figure 3 displays the passenger numbers per year from birth to decline. The modelled curve is a relatively good fit. Despite not matching the rapid drop in tram patronage in the late 1940's, the downward orange curve generally heads in the same direction as the actual data.

From this graph it is clear that there was a decline in tram passengers between 1945 and 1980.



1980-2022
The period between 1980 and 2022 saw the revitalisation of the tram network. Although not as rapid as the initial growth period seen in figure 2, there is a gradual increase in passengers numbers, with the peak growth rate in 1987. The system appears to mature after 2010, and then declines rapidly due to covid. To make the curve fit better, the three data entries recorded during covid were removed and the regression done again. The results are in figure 5 below.

1980-2019
This curve fits slightly better than the curve in figure 4, with an RSQ value much closer to 1. The RSQ value does get higher as the Smax value increases, however an Smax value of 207 provided the best curve fit. It also moves the period of fastest growth to 1989, and the curve flattens out quicker, reaching the maturing stage just before 2010.

Conclusion
Table 3 displays the stages of the transport network life-cycle and the time period for each. Note that data affected by the Covid-19 pandemic after 2019 is not included.