Dunedin City Council staff want to start plans for a walkway and cycleway from Port Chalmers to Aramoana so the project can tie in with repair work on the sea walls.
The proposal would be a "more cost-effective" use of council funds, staff said.
If approved by the council, the walkway and cycleway to Aramoana could be completed 10 years ahead of schedule, which would mean it was finished by 2025.
Widening the road was estimated to cost $1.2 million every kilometre, a report to go to the Otago Peninsula Community Board said.
The report, from council projects engineer Evan Matheson, said the cost of repairing the sea walls would be $6 million, while widening the road in conjunction with repairs would cost $10.4 million, which meant the sea wall renewals budget would cover about 60% of the cost of the widening.
The council had planned to begin widening Aramoana Rd between 2020 and 2025, after widening on Portobello Rd and Harington Point Rd was finished.
The condition of the sea wall along Aramoana Rd was generally poorer than on the peninsula side.
Of the $750,000 the council spent every year on sea wall repairs, $450,000 was spent on sea walls between Careys Bay and Aramoana.
Past repair work had been done in patches not longer than 100m, but now sections of repair work were likely to be up to 200m long which gave a "very good opportunity" to widen the road at the same time.
"Early thoughts are that it would be prudent to widen Aramoana Rd by 2.5m to create a shared 2m footpath/cycleway and an additional 0.5m of carriageway width," the report said.
The widened areas would be backfilled and grassed until there were 1km long sections which could be sealed.
