Rangitīkei District Council has put the total cost of Monday night's flooding at $800,000.
That's according to the council's project engineer for roading, Phillip Gifford, who said the figure was based on the very limited information currently available.
"Extremely heavy rainfall flooded the township of Hunterville, the North Island Main Trunk Railway and the local road network," Gifford said
"The flooding caused numerous slips along a number of roads, particularly Ongo Rd and Turakina Valley Rd."
A 20km length of Mangahoe Rd was extensively damaged and is currently closed.
"As the road runs adjacent to local streams along the bottom of a valley, the overflow from the streams has scoured out significant areas of carriageway and water table and damaged bridges," Gifford said.
Mt Curl Rd has also been closed because of a large slip.
Gifford said they hoped to reopen both Mangahoe Rd and Mt Curl over the next three days.
"Increased resources are being concentrated on the removal of slips and trees and opening the roads.
"We will scope the quantity of remedial work required as a matter of urgency with a view to making an application for Emergency Works funding."