O-Bahn bus on rails an isolated idiosyncratic piece of Adelaide transport ignored by the rest of the world

One of the very occasional cars that strays onto the concrete tracks of the O-Bahn busway to Adelaide's northeast suburbs.
Image courtesy ABC News, Adelaide

Adelaide’s O-Bahn bus-on-concrete rails system from the 1980s became a idiosyncratic but effective transport mode – except for the very occasional car that strays onto its tracks.

But the O-Bahn track remains isolated and unconnected to the rest of the transport system. Nor has the rest of the world taken up the system from its origins in Essen, Germany.

An extended Glenelg tram line to Adelaide’s north-eastern suburbs lost out to the O-Bahn guided busway, opened in 1986. With rapid growth in north-eastern suburban Tea Tree Gully (2,500 in 1954; 35,000 by 1971), land along River Torrens, originally bought for the Modbury freeway under the abandoned MATS (Metropolitan Adelaide Transport Study), was proposed as the route for a branch of Adelaide rail network.A North East Adelaide Public Transport Review chose light rail or a busway as more viable.

The state government decided to extend Glenelg tram beyond Victoria Square and through city parklands to Modbury corridor.  Adelaide City Council joined broad opposition to the project, saying it interfered with the city layout. The government altered the plan to put the tram line underground at big cost. Residents in inner suburbs such as St Peters had concerns about noise and disrupting Torrens Gorge.

The trams possibility was halted in 1980 after premier David Tonkin appointed an opponent of the light-rail project, Michael Wilson, as transport minister. The government sent experts to look at an innovative O-Bahn (omnibus/bahn or path) guided bus developed in West Germany by Daimler-Benz for tram tunnels in Essen. State Transport Authority engineers saw O-Bahn’s advantages (less land, less noise, faster, cheaper).

Plans were drawn up for 12 kilometres (initially, only three) of O-Bahn path. A new government in 1982 brought a fresh look at the choices but premier John Bannon continued with O-Bahn Stage 1 (City to Paradise) and in 1986 Stage 2 (Paradise to Tea Tree Plaza). Costing $98 million, including buses, the O-Bahn had more than four million passenger trips in Stage 1 in 1986, with 30% more the next year. When the O-Bahn was completed in 1989, passengers rose another 17%.