Traffic using the critical Central Otago gateway on State Highway 8 was delayed for about 20 minutes on Wednesday, while NZ Transport Agency staff and contractors conducted a visual and drone inspection of the bridge.
The historic single-lane bridge is earmarked for pedestrian and cycle use once a new $20million, 190m twin-lane structure is completed between 2020 and 2022.
NZTA senior project manager Simon Underwood said Wednesday's assessment would feed into a conservation plan for the existing bridge.
"As part of the project to construct the new bridge, works will also be undertaken on the existing bridge to better provide for its ongoing use by pedestrians, and to conserve its heritage values. It was constructed in 1884 and is one of only a few examples of wrought iron bridges remaining on the highway network.''
In 2016, the NZTA consulted with the public on the location and alignment of a new bridge, and on its design in April this year.
Feedback strongly favoured an alignment just downstream of the current bridge, so the highway could continue to pass in front of the Beaumont Hotel.
Results of the design consultation are still to be released.
Mr Underwood said the new bridge was essential to maintain and improve safe passage via SH8.
As well as being a major tourist route, it was used by trucks delivering aviation fuel to Queenstown Airport.
"It's being designed to handle current and expected traffic volume growth, including heavier trucks, and to meet current earthquake standards. But the historic bridge will still have a role after the new bridge opens, providing a link to the popular Clutha Gold walking and cycling trail.''
The Clutha Gold Trail would pass below the new highway, with a link across the river via the heritage bridge.
NZTA drone technician, coastal Otago maintenance contract manager Nick Rodger, said drivers had been patient while the inspection took place.
"We had a couple of hours set aside, so to wrap things up in two 10-minute blocks was pretty good. People were very understanding.''
