State of emergency in place as West Coast braces for flooding

Forecast heavy rainfall that could cause flooding has seen Civil Defence declare a state of emergency for the South Island's West Coast.

It's feared the rain could bring more flooding after two major flooding events in the past year on the Coast.

MetService has issued a red heavy rain warning for Buller and Westland that took effect last night and runs through to Thursday afternoon.

The rain is expected to cause dangerous river conditions and significant flooding. Slips and floodwaters are likely to disrupt travel, making some roads impassable and possibly isolating communities.

For Buller the forecaster says to "expect a further 280 to 400 mm of rain to accumulate about the ranges south of Little Wanganui on top of what has already fallen, and 150 to 250 mm elsewhere. Peak rates of 15 to 20 mm/h about the ranges on Wednesday".

READ MORE: Expert explains 'atmospheric river' set to soak parts of NZ

For Westland they say "expect a further 250 to 420 mm of rain to accumulate about the ranges on top of what has already fallen, especially between Bruce Bay and Otira, and 100 to 180 mm about the coast. Peak rates of 10 to 20 mm/h about the ranges."

“We have taken the lessons from the last two floods and we have listened to what our communities have told us,” Buller Civil Defence controller Douglas Marshall said.

“We are planning for every eventuality based on the forecast, modelling of the impacts that rain will have on rivers, the risk of high waves to our coastal communities, and drawing on experience.”

He urged people living in low-lying areas to make their own evacuation plans and keep a bag packed with clothing and essential medication for each member of their household. They should also plan for their pets.

Marshall said that as well as the risk of flooding from the Buller and Mokihinui rivers, MetService has issued a warning of coastal swells up to 5 metres high.

There are also orange heavy rain warnings in place until Thursday evening for the Tasman District west of Motueka and The Marlborough Sounds, Richmond and Bryant ranges, Rai Valley and Nelson Region.

Under the orange warning heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous.

In the North Island orange rain warnings for Northland and Mount Taranaki kick in from tonight and run through until Friday.

Buller District Deputy Mayor Sharon Roche told Breakfast that although no evacuations have been ordered yet, she urges residents to be prepared.

"There's no planned evacuation at this stage but obviously if people feel safer by moving out to friends or family at higher ground then absolutely we would encourage that but we will know more after the briefing this morning.”

Roche said this time round, the district has time on their side as they have a fair idea of what may be coming.

She said diggers have been bought into areas they've known to be vulnerable flooding spots in the past.

"This time and residents have been starting to sandbag early so we really are well prepared and I want to assure people that that is the case."

Roche added that residents are understandably very stressed and anxious about how the rest of the week will play out.

“We really are trying to target those areas that we know do flood so we’re giving some reassurance as much as we can to those residents that we will assist them to protect themselves and their homes, so that’s the most important thing at this stage.

“Once again all I can say is we’re doing the best we can and we ask people to be prepared if there is an evacuation called but at this stage nothing official.”

Roche said it's not just Westport expecting wild weather, northern communities should also expect strong winds and large swells.

"We're assisting them to prepare as well," she said.

"We will not be letting down our guard in anyway right until this whole front passes through."

Residents are urged stay well informed and listen to radio reports as the situation develops.

"Keep well informed and take care out there," Roche said.