IMMIGRATION minister Peter Dutton got a towelling from the Senate this week when he couldn’t reach a deal with the crossbench on his legislation to toughen requirements for people seeking Australian citizenship. The bill was […]
STREET-level trams would be an expensive public transport failure because of Canberra’s topography and we can’t afford a true light rail network. Given the likely emergence of driverless-vehicle technology, building busways and improving the bus network is an economical and practical way forward that will not lead to wasted investment.
There was a time when government would have had this type of sound engineering advice, given impartially, from its public service. Mid last century one of the greatest engineering schemes in the world was conceived in the Australian Public Service and managed to its completion by the Snowy Mountains Authority.
Today the legislature can at best be described as a group of social engineers, distracted from the important long term view found in the necessarily conservative approach of engineering by a plethora of lobbyists and developers. The role of engineering is now in the implementation of what is all too often unsound planning. And so we have begun the construction of a particularly inappropriate street-level tram network in Canberra.
There is no question that the motivation of the Barr government is to move Canberra from a collection of towns, each with a longer term potential to be a viable economy, into an all-focusing CBD, attractive to the current under-40 age group. The rationale is the need for population infill and the revenue base that it is claimed is dependent on having rail lines in the street.
Street-level trams are successful and attractive in the long-established cities of Europe. A look at the transport engineering data reveals that the routes are short but numerous, the population densities very high, and the services are frequent. The average trip is just a few kilometres thus the slow, effective speed of the trams is not a major problem. For example, Zurich has 15 routes that cross the CBD, each route is about 10 kilometres long, and the average trip length is about three kilometres. Frankfurt is a similar example having 12 routes.
A true light rail network has grade separation (no intersections with the roadway) and in the Canberra context it would have elevated track (as in Vancouver) with one or two stops between Gungahlin and Civic. It would provide the high capacity and rapid transit that would meet the needs of a growing population for many decades into the future. It would complement the growth of the economy around major centres. However, it would come at a likely cost of $150 million per kilometre compared with the $60 million per kilometre contracted for the Gungahlin-Civic line.
The proposed Canberra street-level network is an unworkable compromise, evident in the design of the Gungahlin-Civic link. The reason is the very low Canberra-wide population density of 430/sqkm compared with Zurich (4000/sqkm). The response of the Barr government is to increase the population along the tram corridor through property development. That makes for an increase in demand for rides but it cannot change the fact that Gungahlin residents on average live more than 12 kilometres from Civic. Thus their journeys are much longer than is the case for the successful tram networks, and that puts the focus on the effective speed of the tram.
There is a twofold compromise aimed at achieving a trip time of 24 minutes, a time well above rapid transit times (less than 18 minutes). Firstly, tram stops are spaced so that walking distances are much greater than in the established networks, thus adding to the overall journey time. Secondly, trams are to have priority over road traffic at the many roadway intersections, which, while services are maintained at six minute intervals, will only increase delays to opposing road traffic by 10 per cent.
However, when the service frequency of trams has to be increased after 2021 to meet the expected growth in population, there will be a more serious impact on the road traffic. When this scenario is translated to the more dispersed towns of Tuggeranong and Belconnen the prognosis is even worse. But this is the lesser part of the problem.
After several decades the complete network will have one tram line along an arterial route in each town, leaving the majority of residents outside the catchment. The proposal is for feeder bus services. This is an unworkable plan. The possibility of using long trams is fraught with many difficulties at the street level, with bridges and catenary-free operation being additional problems in Canberra.
Given that the city will still be reliant on an extensive bus network after the tram network is completed, it would be better to persevere with improvements to the existing bus network, including the construction of bus-ways that can be built at half the cost of rail lines. Buses have the flexibility to deliver both rapid transit and general services. The case for busways is further substantiated by the progress evident in driverless vehicle technology that will use the road network. Fleets of driverless vehicles as public transport will replace private cars without travellers forfeiting the important advantages of driving their own car. Ride sharing and reuse of the vehicles will reduce the overall road traffic and parking requirements for a given population. Clean energy applies to all electric vehicles whether they be tram, bus or driverless car.
Chief Minister, Andrew Barr, cynically spurns the influence that older generations exert in healthy societies. These people have a focus on their local centres for shopping, food and entertainment. They know all the requirements that families have, and the many transport needs that are not met by an inflexible public transport system. In particular, in Canberra, they have lived through the growth of their towns. They appreciate the unique urban form of Canberra and the threat high rise corridors pose to a successful and beautiful bush capital.