Big rocks are still blocking some roads in the Tasman District after torrential rain and flooding.
Dozens of homes and farms were waterlogged, roads have been damaged and about 7000 households were without power.
The Aorere River hit a 150-year peak, washing away two bridges, while nearly 30 houses in the Collingwood area and 13 in Canvastown were flooded.
A spokesperson for Nelson Civil Defence says council contractors are reporting that damage to roads in the Murchison area is worse than expected.
The Maruia Saddle Road is likely to be closed for some time as it is peppered with rocks the size of cars, she says.
Clean-up likely to take months
The clean-up operation in Marlborough after the worst floods in decades is likely to take months.
Ross Hamilton, a Civil Defence controller at the Marlborough District Council, says authorities are working hard to reopen access in the region.
Water and sewerage systems have been repaired and are operating at normal capacity.
Mr Hamilton says it is too early to calculate what the floods have cost the region and damage to private properties is a matter for the owners and their insurance companies.
