Extensive soil testing for a proposed $42 million highway project in Caversham Valley, Dunedin, will begin this week.
Contractors working for the New Zealand Transport Agency (NZTA) will carry out topographical (ground level) surveys and geotechnical testing (of sub-surface material) for foundations of two proposed bridges on State Highway 1.
Construction of a four-lane arterial route from Andersons Bay Rd to Lookout Point would require construction of two new bridges at the Glen and near Lookout Point.
At the Glen, a longer and wider bridge would carry two northbound traffic lanes and the existing bridge two southbound lanes.
Test holes will be drilled alongside the existing bridge.
A second bridge at Lookout Point, close to the South Rd intersection, would provide a direct link over the highway between Mornington Rd, Riselaw Rd and South Rd.
The Lookout Point bridge would be over 6m high to allow oversize load carrying vehicles under the structure.
Up to 60 smaller tests (up to 4m deep) would also be drilled in other areas to test suitability for pavement upgrades.
NZTA regional projects manager Simon Underwood said testing started last month but was delayed while contractors located water, sewerage, and electricity services.
While some "ifs and whens" surrounded the project, the agency was "very, very confident a big chunk will go ahead", he said.
Investigations would be based on an extensive project so savings could be calculated if the scale of construction was reduced in future.
The agency did not want to present the public with "too many unknowns" during the consultation process next year, he said.
At a Dunedin City Council infrastructure services meeting last month revised designs were discussed, which would see access blocked at certain points on the highway for safety reasons, and an overbridge built to allow motorists to cross the highway.
Those wanting to drive south from the Lookout Point area would have to join the highway at Concord.
Opus project manager David Boniface told councillors the design would be presented for public consultation ahead of an NZTA regional funding hearing next year, but was not definitive at all.
NZTA regional network manager Murray Clarke last month told the Otago Daily Times the exact price and funding arrangements were yet to be confirmed, but costs were estimated at $42 million.
The highway project would be considered for funding by the NZTA regional funding committee in April, but he was confident existing design issues could be resolved before of any decision.
Testing would be completed by January.
