Transport Minister Michael Wood has hinted that heavyweight trucks may only be able to cross Auckland's ageing Harbour Bridge at restricted times of day.
It comes after Waka Kotahi revealed it's not possible to do any more strengthening work on the bridge due to the weight of the steel that would need to be added.
Instead, "active traffic management" will need to be introduced.
Wood told the Herald this could mean managing access to the bridge by heavy vehicles, which potentially create the highest levels of risk.
"That would most likely mean, were it to occur, a conversation with that sector and looking at the hours of the day which those vehicles most commonly access the bridge, which tends to be around 3 o'clock or 4 o'clock.
"What you can create is a reduction of the very heavy vehicles which, in the wrong circumstance, could create the heaviest risk of some kind," Wood said.
But he said there was no plan to implement any change to commuters or freight services accessing the Harbour Bridge yet.
"There's no need for that at the moment and there's no active plan to do it but we do need to have contingencies in place.
"We continue to constantly review the bridge."
Meanwhile, Auckland's Chamber of Commerce chief executive Michael Barnett told Newstalk ZB it was costing "millions of dollars a day" whenever traffic was diverted because of strong winds on the bridge or roading needing to be fixed.
"For Auckland, we seem to wait until there's a problem and look to fix it instead of being strategic and looking ahead, knowing we are growing at 50,000 people a year, knowing we have to do the infrastructure and just talking about it instead of doing something," he said.
Waka Kotahi general transport service manager Brett Gliddon the "active management of traffic" would not be needed within the next 12 to 18 months but did not elaborate further on a timeframe.
Talk of restrictions has also renewed calls for an alternative harbour crossing to be prioritised to prevent the city from coming to a standstill in the future.
The revelations came at the annual review of Waka Kotahi New Zealand Transport Agency at a parliamentary select committee yesterday.
After a question from National MP Christopher Luxon, Gliddon said it was no longer possible to strengthen the bridge, which is crossed by 170,000 vehicles on weekdays.
"We believe we've strengthened it as much as we possibly can and we can't add more steel into it ... it's counter-productive."
He said maintaining the "structural integrity of the bridge" could involve restricting heavy vehicles, limiting the lanes they could use, the number of heavy vehicles on the bridge at one time, or the time of day they cross.
Road Transport Forum chief executive Nick Leggett said the fact remediation work was no longer an option was concerning given the lack of alternative options and there needed to be urgent plans for another crossing.
"Auckland is a key arterial route through our biggest city and our biggest economy.
"We don't accept that there isn't a budget for this, and there needs to be priority given. Any sort of build needs to start in the next two or three years."
Auckland came to a standstill last year — and people were asked to work from home — after two trucks were blown into the bridge in wind gusts of up to 127km/h, damaging its structural integrity.