The task of mopping up Great Barrier Island's flood damage will cost more than $10m, civil defence say.
Storms that battered the small island last Tuesday night have left the main road, walking tracks, campsites and huts out of action until further notice.
The wild weather was believed to be the biggest storm to hit the island in living memory, Auckland Civil Defence Controller Clive Manley said.
He said the island endured storms in the past, such as Cyclone Bola, "but the general consensus is that the impact of this particular storm is the worst that people can remember"
Civil defence has been tasked with rebuilding the island's damaged infrastructure.
The immediate priority was to get the roads - including main street Aotea Road back open for motorists.
It was likely to run into a $10m-plus clean-up job, while the longer-term economic implications could push that figure even higher, Manley said.
The rebuild was still in the initial response recovery phase and could take months to fix major infrastructure.
Chair of Great Barrier Island Community Board Izzy Fordham said the community spirit remained positive.
She said people were glad the damage wasn't worse.
"The fortunate thing is nobody's lost a house. Everyone's still got shelter and warmth which has been great. On the whole we consider ourselves incredibly fortunate."
Fordham said she was urging people to stay off the main street - Aotea Road - as it underwent repairs.
The department of conservation said a number of facilities have re-opened including Medlands Beach campground, Awana Beach campground, the Hot Springs Track (only to the hot springs, not beyond), and Windy Canyon Track and Palmers Track to the Hirakimata summit - (no tracks continue from the summit, so return is by the same route).
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