The Tasman District Council is attempting to retrain the Aorere River to flow back onto its original course.
Fine weather over the past few days has helped clean-up efforts in one of the Golden Bay communities worst affected by flooding this week.
Peter Thomson from the council says the river rose rapidly and flowed into back channels.
He says the lower part of the Aorere flood plain was inundated with water, damaging some houses and fences and causing the loss of some stock.
Mr Thomson says the water rapidly receded and earth and rockworks are now being put in place to make sure the river does not change course again.
Residents in the Pohara region must continue to boil water because it has been contaminated as a result of flood damage.
Farmers thankful for help
Farmers in flood-hit Golden Bay at the top of the South Island are paying tribute to large numbers of volunteers who helped clean up their water-logged homes.
A severe storm this week caused the Aorere River to burst its banks, change its course, and lose a swing bridge and a road bridge to surging waters.
Federated Farmers regional president Graham Ball says recovering from the flooding will take time but it was great to see friends and volunteers helping out.
The main tasks now are repairing wrecked bridges and providing feed to livestock who will not graze on silt-covered paddocks, he says.