The NZ Transport Agency has confirmed State Highway 60 at Birds Hill - linking Takaka and Collingwood - is now definitely open to single-lane traffic.
NZTA announced the road would open at 4pm on Saturday but several hours later a motorist contacted Radio New Zealand News to say she was stuck in traffic on the road.
According to her information, the road had been closed again after Fonterra milk trucks had managed to get through.
NZTA says vehicles are definitely using the highway again, but drivers should be cautious.
Earlier, the agency said motorists using the road should expect delays.
Operations manager Mark Owen said road crews had done a superb job in getting a single lane of the road open after a major slip on Thursday completely undermined it.
In other major road closures, State Highway 6 Rocks Road in Nelson city, remains blocked to all traffic by a major slip.
NZTA says it will stay closed until geotechnical experts are satisfied the rock face is secure.
Mr Owen says it may be up to six months before highways damaged in the storm are completely repaired.
He says there is a massive reconstruction job ahead and the first priority will be to get temporary access.
Mr Owen says in many places there may only be one-lane access or motorists may have to use unsealed roads, but he says it will at least allow people to get to and from their properties.
Convoy for Pohara residents
Residents are being provided with an escorted convoy to get between Pohara and Tata Beach and Ligar Bay.
Convoys between Pohara and Tata leave Pohara Hall at 8am, 12 noon, 4pm and 7pm daily while the return convoy will leave Tata Beach at Peterson Road at 8.10am, 10.10am, 12.10pm, 4.10pm and 7.10pm.
Civil Defence is stressing that return travel must be with the convoy and if they miss the allotted time, vehicles must wait for the next scheduled departure.
The roads affected by the storm in the Nelson-Tasman region include:
Glenview Road is closed as a through route at the bridge, but access available from each end.
Upper Rocklands Road is closed but Rocklands Road is now open.
Bird Road is closed long term.
Abel Tasman Drive is closed at Pohara Hall to Wainui Bay.
Both Totaranui Road and Awaroa Road are closed for up to three months but have boat access.
Rameka Creek Road, Matata, Pohara Valley Road and Hamama are all closed.
Rameka Creed Road is closed long term.
Falconer Road (also known as Faulkner Road) is closed.
Waimea West is now open, but the hill section of Aniseed Valley Road is closed between Haycock Road and the top of the hill, and then from 2km past Mead Road.
This is a long-term closure and an alternative access is available via a private forestry road via Lee Valley and Mead Road. Traffic is restricted to 4WD and during daylight hours only.
Wairoa Gorge is open 1km from the Brightwater side of Forks Bridge.
Streets still closed are Little Todd Valley Road, Konini Street, Grenville Terrace, Cable Bay Road, Iwa Road, Grampian Road (access to transmitter) and Beatson Road.
Raynor's Road is now open to single lane traffic but use is restricted to residents only.
Recreation areas and walk- and cycleways
Closed walkways, cycleways and recreation areas include:
Rabbit Island Front Beach Reserve.
Days Track on Tosswill Road, Princes Drive and Moncrieff to Grenville Terrace.
Maire Street Track.
Seaview Cycle underpass.
Orchard Stream Cycle underpass.
Railway Reserve from St Vincent to Beatson.
Main Road Stoke underpass.
Dellside Reserve walkways.