Rivermouth closes causing Clive River flooding

The Clive River flooded at Evers-Swindell Reserve after the rivermouth closed. Photo / Warren Buckland

A low flow led to an overflow for the Clive River on Monday, with the Evers-Swindell Reserve being flooded after king tides and low river levels combined to close the rivermouth.

The Hawke's Bay Regional Council engineering officer schemes, Luke Davis, said in summer low river flows can combine with large easterly swells and cause rivermouths to close, as the confluence of the Ngaruroro, Tūtaekurī and Clive rivers did on the weekend.

"This can cause flooding upstream, like what we saw at Clive's Evers-Swindell Reserve," Davis said.

High tides hit properties at Haumoana on Tuesday. Photo / Warren Buckland

Mechanical reopening of the river was undertaken at the 2:15pm low tide on Monday, when swell and tidal conditions were more favourable.

MetService meteorologist Lewis Ferris said autumn is coming for Hawke's Bay this week, with chances of wet weather on Thursday and Saturday in between fine spells.

"Definitely this week has a good autumnal flavour to it with the fast-moving fronts, and actual weather whereas it had been relatively settled beforehand," he said.

"We do have a front that will be heading up [on Sunday] with a bit of a southerly flick to it," Ferris said, adding that it would see temperatures cool off next week, particularly overnight.

Luke Davis, from the Hawke's Bay Regional Council, said in summer low river flows and large easterly swells can combine to close rivermouths. Photo / Warren Buckland

Niwa's seasonal outlook for March, April and May came out on Monday as well, predicting typical conditions for Hawke's Bay.

It said temperatures are most likely to be near the average (45 per cent chance), rainfall totals are most likely to be near normal (45 per cent chance), soil moisture levels are most likely to be near normal (45 per cent chance) while river flows are equally likely to be near normal (40 per cent chance) or below normal (40 per cent chance).

Abnormally dry conditions are occurring across Hawke's Bay according to Niwa's New Zealand Drought Index.