Tonga eruption and tsunami: ACT calls out Civil Defence for not activating tsunami sirens before surge hit New Zealand

The ACT Party is calling out Civil Defence for not activating the emergency mobile alert system and tsunami sirens before strong surges hit Northland following Tonga's devastating volcano eruption.

A 1.2-metre tsunami hit Tonga on Saturday after Hunga-Tonga-Hunga-Ha'apai erupted for eight minutes, throwing ash into the sky.

A tsunami warning was triggered for New Zealand and many areas were warned via social media about potential strong currents and coastal surges, including Tutukaka in Northland.

Many boats moored at the marina were damaged after large swells reached the area. But ACT's Civil Defence spokesperson James McDowall says no tsunami alerts were issued specifically for Tutukaka and this "put lives at risk".

"We have these systems in place for a reason, to protect lives and property. Kiwis shouldn't have to rely on proactively checking Minister Kiritapu Allan's Facebook page for warnings," he says.

"Residents are now picking up the pieces and adding up their losses, well into the millions of dollars. The marina itself will require extensive repair. 

"Those who were living in their boats are thankful that they managed to get out in time, but cannot believe the radio silence after years of receiving mobile alerts and hearing sirens for minor events."

Tutukaka local Steve Callagher also says there weren't any tsunami sirens.

"Even an hour after the event there were still people down here with major surges and carnage," he tells Newshub.

"Perhaps Civil Defence dropped the ball on this, I'm not sure."

Civil Defence issued a national advisory across their social media and website just after 8pm on Saturday warning New Zealanders near the coast of strong and unusual currents and unpredictable surges. They have also given updates throughout Sunday of any changing coastal conditions and insist the area is well-prepared for tsunami events.

"There are aspects to the way Tutukaka is formed that might amplify the tsunami activity that takes place," says Murray Soljack from Northland Civil Defence.

"Generally you'll find when there's no noticeable effects elsewhere, there will be noticeable effects at Tutukaka."

Tonga eruption and tsunami: ACT calls out Civil Defence for not activating tsunami sirens before surge hit New Zealand
Photo credit: Supplied / Aaron Dyer

Prime Minister Jacinda Ardern says a "precautionary approach" is being taken for New Zealand following Tonga's tsunami.

"There was obviously the statements made by our National Emergency Management team to just be aware, stay away from those coastal areas, expect that it would be likely that we would see unusual behaviour and surges, and that for a period of time it would be better to be away from those coastlines," she said during a press conference on Sunday.

"There have been some precautionary acts as well for certain areas, particularly where there was camping involved. But of course, in an unpredictable environment, we'd much prefer to take that precautionary approach."

Ardern also says that while people may find the surging swells interesting, they are warned to be careful and stay away.

Whether there would be further alerts issued for Northland would be up to Civil Defence, she added. There is still a national advisory on their website telling people to stay off beaches and shore areas.