Waka Kotahi is considering delaying a planned closure of State Highway 1 over the Brynderwyn Hills for slip repairs following an outcry from Northland businesses.
The transport agency originally wanted to shut the vital route for seven weeks between Waitangi Day and Easter.
However, after protests from businesses still recovering from Covid-19 lockdowns and last summer's road closures, Waka Kotahi is now consulting on whether to stick to the original timetable or delay the work until after Easter.
If the work is delayed it is likely to take longer, 10 weeks instead of seven, and cost more, $66 million instead of $61m.
The longer closure after Easter is due to the greater number of rain days expected at that time of year.
Waka Kotahi has previously said if the work is not done before winter the highway could fail entirely, leading to longer, unplanned closures.
The road was closed for weeks on end last summer while emergency repairs were carried out.
A spokesperson for Waka Kotahi said a full road closure was needed while longer-term repairs were carried out, because cutting into the upslope would pose a risk to motorists from material falling onto the lanes below.
Also, the number of underslips meant there was not enough shoulder width to accommodate equipment while traffic lanes were open.
"Scheduling a closure to complete these vital works allows the Brynderwyn Hills to withstand future weather events over the immediate to medium term, significantly reducing the need for unplanned emergency closures, which were experienced frequently earlier this year," the spokesperson said.
Planned work included widening the road shoulder so future repairs could take place with less disruption to traffic.
The highway would also be moved further towards the hill, away from the current road edge which was susceptible to further slips.
An estimated 150,000 cubic metres of earth would be moved.
The agency said it was conducting the survey because it wanted to understand how the closure's timing would affect stakeholders such as the tourism industry and freight.
Feedback was needed by 10 December.
When word first filtered out about the closure - at that point scheduled to start on 7 February - a concerned Kerikeri District Business Association called a meeting of its members, other business groups, representatives of all four Northland councils, the AA, and Waka Kotahi's regional relationships manager Steve Mutton.
Waka Kotahi subsequently agreed to consult further before making a decision about timing.
During the 17 November meeting, Business Paihia chairperson Charles Parker said he had had half a dozen emotional pleas from business owners saying another closure would ruin them.
They had already lost two summers due to the Covid-19 pandemic and another due to bad weather and road damage caused by Cyclone Gabrielle, and they could not afford to lose a fourth.
Waka Kotahi is also holding "webinars" at 6.30pm on 6 December and 10.30am on 8 December. Each will include a presentation followed by a public Q&A session.