Clutha District Mayor Bryan Cadogan said he was disappointed to hear NZ Transport Agency (NZTA) was investigating making Balclutha’s main southern exit on State Highway1 one lane in order to cut repair and maintenance costs.
At present, an 800m stretch of the highway up Rosebank Hill, between Hospital Rd and the Rosebank Lodge, has two lanes, allowing vehicles to pass trucks slowed by the hill.
Only two further passing lanes exist on SH1 between the lodge and Clinton, 28km to the west.
Mr Cadogan said the removal of a lane would be a disappointing step backwards.
"This is a road of national significance and, with recent budgeting, can we not at least hold on to the roads that we have?
"There are so few passing lanes on [SH1] and the road is so dangerous for passing elsewhere, that maybe NZTA just want it suitable for horse and cart use.
"If we lose this passing lane, we’ll only see frustration from motorists leading to a decrease in safety. Let’s look forward, and simply maintain what we have properly for now."
NZTA Otago senior structures network manager Michael Tannock said the lane reduction was being considered principally to save money.
A staff report to a recent council committee meeting said the two-laned section of highway also presented some safety concerns.
Mr Tannock said the road had a history of defects.
"[T]here is a history of the left lane developing defects and the site has been planned for repairs.
"The current passing lane would likely require extensive drainage work and pavement works to rebuild.
"The cost to rebuild the passing lane may be out of proportion to the benefit that it provides given the remaining lane can service traffic capacity and flow adequately."
The council report said removing the left lane would also move trucks further away from the pedestrian footpath, and allow cars turning on to the highway to merge from the left safely.
Mr Tannock said a final decision on the road’s future was yet to be made.
"Alongside the possibility of removing the passing lane, options include rebuilding in the current configuration. NZTA is in the investigation and design phase currently, potentially undertaking this work this financial year."