City Loop, Melbourne
The City Loop is a railway - mostly underground, but partly surface-level, and partly elevated - that encloses the central business district of Melbourne, Victoria, Australia. It contains 5 stations, 3 of which are underground. The stations include the city's two largest (and the two above-ground): Flinders Street and Spencer Street stations; as well as the submerged Flagstaff, Melbourne Central (formerly Museum), and Parliament stations.
Melbourne's 16 radial suburban railway lines feed into the Loop at its northwestern and southeastern corners. The underground section of the Loop follows La Trobe and Spring Streets along the northern and eastern edges of the CBD's street grid.
Photography was banned in the Loop in 2004, much to the disappointment of Melburnian railway enthusiasts.
Problems and solutions
Prior to the construction of the Loop, Flinders Street and Spencer Street stations were connected only by a viaduct beside the Yarra River. Flinders Street, the suburban terminus, had become seriously congested by the 1970s, with a turnover of only 10 trains per platform per hour (roughly 1,700 trains a day); not enough to satisfy the city's growing needs. The problem lay in the fact that trains had to change direction at the station to return to where they had come from; thus taking up valuable track space and time.
Several plans had been proposed over the preceding decades to alleviate the bottleneck, but none were to see the light of day. That is, except for the concept of a circular railway allowing trains to continue past Flinders Street, turn around and return to the suburbs. The City Loop was accepted as the solution to the platform capacity dilemma, allowing up to 24 trains per platform per hour at Flinders Street, in both directions (around 4,100 trains a day). The Loop would also bring train commuters directly into the CBD, dropping workers closer to their offices, students closer to RMIT University, and bringing government officials directly to the Parliament buildings, among many other things. (Although the city's tram network already extensively covered the CBD, trams are not as efficient as trains when bringing large numbers of suburbanites into the city).
Construction
The Melbourne Underground Rail Loop Authority (MURLA) was created in Febuary 1971 to oversee the construction and operation of the Loop, and the Melbourne Underground Rail Loop Act (1970) paved the way for the project to begin. Tunneling works commenced with the turning of the first sod in June 1971.
The Loop comprises four single-track tunnels over two levels. As well as these tunnels, an extra two elevated tracks were provided between Flinders Street and Spencer Street stations, on a new viaduct beside the old. Of the three stations, Museum was built using the "cut and cover" method, while Flagstaff and Parliament were excavated using mining methods. During the excavation of Museum station, La Trobe Street and its tram tracks were temporarily relocated to the south onto what is now the Melbourne Central shopping centre.
The total length of tunnels in the Loop comes to 12 km, 10 km of circular tunnels and 2 km of box tunnels. Each of the four tunnels has an average length of 3.74 km. A further 1,000 m of track connects those underground with those on the surface. Some 900,000 m3 of earth was removed and 300,000 m3 of concrete poured to form the stations and line the tunnel walls. 30,000 tons of steel reinforcement were used, with another 10,000 tonnes used temporarily during construction.
Opening
The system was opened gradually between 1980 and 1985, with commuter trains travelling through the tunnels but not stopping at any station between 1980 and 1981. Museum opened first on January 26, 1981. Subsequent to that, Parliament was opened on January 22 1983 and Flagstaff on May 27 1985. Queen Elizabeth II toured Museum station during her 1981 tour of Australia. A 14-minute documentary film, Loop, was commissioned by the MURLA to advertise the new railway to Melburnians, as well as abroad.
Future expansions
The Victorian Government has intimated that the Loop could be expanded with the addition of a further two tunnels on a third level. Even though the Loop (and particular tunnels especially) is slowly approaching capacity, any extension would not occur for at least 20 to 30 years at current service levels. Other, even more precarious plans have been sugessted that would see a new linear underground railway running through the city centre from north to south, following the line of Swanston Street. Neither plan is being considered at present, however, as demand is not yet sufficient.
Services and direction of travel
All suburban trains terminate at Flinders Street; some having travelled through the Loop first; some travelling directly to Flinders Street, then through the Loop; and a small number of others that still change directions at Flinders Street, (just as all train did before the Loop was built).
There was also a special City Circle service which circled continuously around the Loop to provide cross-CBD travel; this service has now been discontinued with trams providing the alternative.
The direction of travel changes in each tunnel according to the time of day and day of week; as shown in the table below. Each suburban line belongs to one of four groups, each group running through one tunnel. The direction change occurs between approximately 12:30 and 1:00 PM; during which time no trains run through the Loop.
|
| Burnley group
| Caulfield group
| Clifton Hill group / City Circle
| Northern group
|
| Weekday mornings
| All trains run through Loop first
|
|
| Anti-clockwise
| Anti-clockwise
| Anti-clockwise
| Clockwise
|
| Weekday afternoons
| All trains run to Flinders Street then through Loop
|
|
| Clockwise
| Clockwise
| Clockwise
| Anti-clockwise
|
| Weekends
| All trains except Caulfield group run to Flinders Street first
|
|
| Clockwise
| Anti-clockwise
| Clockwise
| Anti-clockwise
|
External links and maps
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- (the source of much of this article)
- (a more detailed explanation of the five train direction configurations)
