Motorists will soon be using all four lanes of Dunedin's new $19 million Southern Motorway extension at Caversham.
The first phase of a larger highway development, estimated to cost up to $45 million, to make the entire 13km stretch between central Dunedin and Mosgiel four lanes will be open this month.
Stage one comprised duplication of the former two-lane highway at Caversham between the King Edward St overbridge and Barnes Dr.
Project manager Simon Underwood said those four lanes should be open by the end of July, although traffic controls would remain in place while guard-railing and landscaping was finished.
"That will take us through into August, so speed restrictions will apply until then," he said.
Overall, the project was on track and Mr Underwood was pleased with the development to date.
A formal opening of the highway extension was planned for October, and after Christmas the final smooth asphaltic cement (AC) layer would be laid on the chip seal surface.
"Motorists will be driving on a temporary surface and if there is any settlement it can be corrected prior to the final AC layer going down," he said.
The project's second stage involved development of the highway from Barnes Dr up to Lookout Point at the intersection of Mornington Rd, and was expected to cost between $20 million and $25 million.
Mr Underwood said he hoped construction of phase two could begin soon after completion of the first stage, but it had yet to get the final sign-off.
"There are land and funding steps to go through. It's our plan to carry on with the work up the valley but there is that caveat," he said.
Once begun, phase two would take about two years to finish.
Mr Underwood praised motorists for their patience during the development.
