Hundreds of farms damaged by floods

Thousands of hectares of farmland have been affected by this month's flooding in Whanganui, Civil Defence says.

A state of local emergency remains in place in Whanganui more than a week after the town suffered its worst-ever floods.

Up to 200 people in rural areas remain cut off, and are having supplies delivered by helicopter. One hundred houses in the urban area have been declared unsanitary.

Whanganui civil defence controller Jonathan Barrett said between 300 and 500 farms had been affected.

He said it would cost tens, if not hundreds, of millions of dollars and take many months to get the area back to normal.

Federated Farmers Whanganui president Brian Doughty said some farmers in the lower North Island have had to sell stock, including pregnant ewes.

Meanwhile power has now been restored to all Whanganui and Taranaki residents.

Powerco reconnected the remaining pocket of isolated Waitotara customers at the weekend.

But it said it would take months to repair some sections of line undermined by slips, fallen trees and flooding.

Powerco said it was keeping a close eye on the weather, as parts of the network were fragile and it would not take much rain to cause disruption.