The Ngaruroro River in Hawke's Bay during Cyclone Gabrielle. Photo: Supplied / Dawson Bliss
Emergency work to reduce the risk from breached stopbanks has been completed by the Hawke's Bay Regional Council.
The council says it is moving on to longer lasting repairs costing tens of millions of dollars.
Cyclone Gabrielle breached stopbanks in 30 places, most on the Tūtaekurī and Ngaruroro Rivers between Napier and Hastings, and including five on the Waipawa River.
This amounted to 5km of damage out of 248km of stopbank.
It was "major damage" that "will take time to fully repair", the council said.
Three stopbanks had been repaired already, with tidy up work carrying on - Maraenui golf course, Allen Road and Taradale - out of 20 sites where they were needed.
Another 13 were being worked on, which would be completed over the next few months.
"Our insurance and Civil Defence payments will reimburse some of regional council's costs, but we are also working with central government on what additional support we will need to cover the shortfall," Hawke's Bay Regional Council group manager of asset management, Chris Dolley, said.
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The initial emergency work was to "protect communities from the weekly forecast rainfall we had been receiving", manager of regional projects Jon Kingsford said.
"All temporary works have been put in place."
A map of the breaches was provided by the council, but it said this was from Thursday 28 February and was now out of date.
The stopbanks are in green, along the Tūtaekuri River at top, and Ngaruroro River at bottom; the red lines show the breaches. Photo: Supplied / Hawke's Bay Regional Council
The Tūtaekurī stopbanks were built following the 1931 earthquake, and the Ngaruroro ones in 1960.
They had many upgrades since, the council said.
"We have started a full analysis of the event and the flood protection network including stopbanks, pumping stations, river-edge tree protection and more," it added.
After Cyclone Gabrielle, the Tūtaekurī River partly went back to its old path.
The stopbanks did not burst their flood banks, the council said.
"Stopbanks were overtopped, through-erosion occurs when this happens - a number of breaches developed where the stopbank was washed away. In some locations structures like bridges, and built-up material on the bridges has led to overtopping."
