As Adelaide's population continues to grow, it's inevitable that pressure is going to mount on the city's road infrastructure. However, this isn't going to be at the expense of Adelaide's parklands, the government told media late last month.
The current state government promised before the last election that it would extend the O-Bahn bus track via a tunnel. This would stretch from Hackney Road straight through to the priority bus lanes in Adelaide's CBD. Instead of this, the plan has now been revised, which will mean two parks (Rymill Park and Rundle Park) will be reconnected for public use.
The bus tunnel
The $160 million bus tunnel promises to cut up to seven minutes off travel times for commuters in Adelaide and should provide the public with a viable alternative to driving their vehicles in the central city.
At 500m long, work is expected to begin on the tunnel by the end of the year. It should be open to bus services towards the end of 2017.
The Royal Automobile Association (RAA) welcomed the tunnel extension route and explained the benefits of such a project to Adelaide.
"Creating a more direct path for the O-Bahn to take into the city will also help to improve public transport, by taking those buses off the road," RAA Senior Manager Road Safety Charles Mountain said in a February 25 media statement.
"The inner city ring route has been nearing its capacity in recent years, so any project to alleviate some of that pressure is welcomed, particularly as this will have positive impacts on traffic flow in the north-east corner of the city."
For this type of project to be a success, it will be important that the tunnel is able to perform under pressure for many years to come. This will require international standard waterproofing to achieve 100 year design life for the structure with specifically designed infiltration management systems to protect the concrete structure.