Fears after 'worst flooding in 10 years' near Tangoio

A clear sky but the water remained. Photo / Supplied

A forecast for heavy rain at the end of this week has residents of a small locality north of Napier worried after recent flooding.

Barry Hoskin says the July 3-4 flooding in the area of the Te Ngarue and Pakuratahi river mouth was the worst he'd seen in 10 years and each new rain event could be worse.

The flooding spread across crops. Apart from the usual threats, it causes potentially damaging salination to crops, says Ngati Pahauwera Development Trust chairman Toro Waaka, whose trust also has land in the area.

The issue, they say, is the closing and opening of the river mouth, amid the massing of silt and debris washed down from the valleys in the catchment.

Hawke's Bay Regional Council asset management group manager Chris Dolley said the council monitors and manages 16 rivers between Porangahau in the south and Mahia in the north, and conducts river mouth openings for the purposes of flood mitigation, as permitted under the Regional Resource Management Plan.

The council's level of service is around public health, public safety and protecting major transport routes and habitable buildings and does not include short-term flooding of farmland, orchards and the like, but the council does try to minimise all flooding where it is "practical and prudent to do so", he said.

Flooding spread across cropping land towards homes in the area. Photo / Supplied

He said that on July 3 river levels rose following high swells of more than three metres.

"The river mouth was inspected the previous day and water levels were found to be low and there was scouring of the beach crest indicating that the river mouth was operating," he said.

"No opening was scheduled for Friday, because in swell and tide conditions, often the river will rapidly block after opening with large swells," he said.

Opening was also dependent on the tide and needed to be done at specific times of the day, typically co-ordinated with a low tide.

He said that on July 4 the river was opened after consultation with a local community representative.

Staff inspecting the area the next day noted the river mouth was open and the lagoon level low.

Showers and drizzle are forecast during this week with heavier rain expected at the weekend.