Wairoa's Mayor is demanding an apology from the Hawke's Bay Regional Council after last week's flooding.

The bill is expected to top $40 million, with more than 100 properties significantly damaged.

The district is still recovering from Cyclone Gabrielle last year, and ratepayers are already facing a 20 percent rates rise.

Mayor Craig Little says the council hasn't been able to pinpoint what went wrong.

"They treat us like we're a small population, yet we're 30 percent of the land area of Hawke's Bay, 60 percent of the water mass - they do other things down there and they don't do it here."

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