Cocurullo said there was a “significant” underslip on the south side, which would take time to remedy.
“If everything goes well, that’s awesome. However, I don’t believe that should be the final fix, I think the final fix should actually moving away from using the Brynderwyns.
“It’s got to the point now where we really need to do some serious work.”
Little work had been done on the road since the improvements on the north side around 10 years ago, Cocurullo said.
Waka Kotahi has given an estimate of “up to four weeks” before access can be provided to all vehicles, although it said it hoped to have controlled access before that time. No date has been given for reopening.
Light vehicles are currently having to detour through Mangawhai, where multiple trucks and trailers have become stuck on sharp bends on Cove Rd since the SH1 closure.
On Monday, Northland Civil Defence banned truck and trailer units from using Cove Rd, but another got stuck yesterday.
The detour for heavy vehicles is SH12/14 via Dargaville, which adds up to an hour each way from Whangārei to Auckland.
Heavy vehicles below 50 tonnes with destinations south of Whangārei may use the Paparoa-Oakleigh Rd, Civil Defence advised.
While a timeline has not yet been announced for re-opening SH1 through the Mangamukas, Waka Kotahi announced today that emergency protection work on the road has been completed.
Permanent works for slip repairs were due to begin this week, and a timeline for re-opening was expected to be available by the end of the month.
The road has been closed since last August due to major slips after heavy rain.
Waka Kotahi project director Norman Collier said reconnecting Far North communities was the agency’s priority, and work was being done to ensure slip repairs were run as “safely, smoothly and quickly as possible”.
The gorge would have to be stabilised and strengthened before large machinery could be brought in to complete slip repairs.
Collier said Waka Kotahi was investigating how the road could be improved and futureproofed so that it could withstand weather events.
“We’ll be investigating this from a national perspective, as many parts of the State Highway network will be challenged with resilience issues in future due to climate change. This work is especially important given recent weather events.
“We know communities are eager to understand when the gorge will reopen, and we will share a timeframe as soon as we have it confirmed.”