Be prepared call as cyclone looms
People in flood-risk areas in Nelson will not be given sandbags by the council, and need to have emergency supplies and an evacuation plan ready as tropical cyclone Gita approaches New Zealand.
Anyone flooded during the last two severe weather events this month were ‘‘strongly encouraged’’ to take precautions to protect their property, Nelson Tasman Civil Defence emergency management warned.
The MetService said yesterday ‘‘a period of highly impactful severe weather’’ was likely across central and northern New Zealand on Tuesday and Wednesday, with ‘‘high confidence’’ of severe gales and heavy rain.
Cyclone Gita was expected to approach New Zealand from the northwest, but uncertainty remained over its speed and track.
Large waves were likely, with a storm surge expected to ‘‘allow run-up of waves in some low-lying coastal places, particularly at high tide,’’ the MetService warned.
At a Nelson City Council briefing this week about the clean-up after ex-tropical cyclone Fehi, utilities manager Margaret Parfitt said the council didn’t ‘‘have the capacity’’ to provide sandbags, and people could get them at hardware stores.
On February 1, scores of homes on Nelson’s Monaco Peninsula and in Tasman district’s Ruby Bay were flooded by the sea, when the remnants of Fehi brought heavy rain to the Western Ranges, and gales across the region, amid a significant ocean swell at king tide.
The tide reached 5.42 metres, nearly a metre higher than expected.
The council would not have done things differently had that tide level been forecast, representatives at the briefing said.
The storm was well-forecast, with warnings put out on the Nelson Tasman civil defence and council websites and Facebook pages, civil defence group controller for the two regions, Roger Ball, said.
But the exact effects of the storm were uncertain.
‘‘I don’t think it would have been possible or feasible to predict to that level of specificity to tell certain people to get out.’’
Ball acknowledged some people didn’t follow social media, and urged affected communities to ring each other up, or knock on each others’ doors ahead of such severe weather events.
‘‘The general messages are, have your three day minimum kit ready and your evacuation kit and plan for your home. And that’s around the idea that if you have to leave when it’s dark, what will you take and where will you go?’’
Anyone protecting their home with sandbags, needed to do so no later than the day before severe weather was expected to hit. Nelson Mayor Rachel Reese told the meeting that February 1 was not the worst case scenario.
‘‘The worst case scenario would have been Sunday night [Feb 11] and what we had on the 1st. That would really have tested us.’’
Prolonged heavy rain on February 11 caused parts of the Maitai River to overflow in central Nelson, along with rivers and streams across the region, with slips and flooding blocking roads.
Flood-risk areas were continuing to be mapped as part of an ongoing review of the city’s draft long term plan.
The plan had to make an assumption about climate change, Reese said.
‘‘Given our coastline, and the number of assets that are in public ownership sitting around there, we have to take this very seriously, and we have been in our planning.
‘‘But we have to take the community with us on this, because together we’re going to have to decide how we manage the risks.’’
The council didn’t have the financial capability to protect everything, and wanted to stay within rates caps, she said.
‘‘The next conversation with the community becomes a whole lot harder ... what do you protect first?’’
As for Monaco, there was no imminent policy, said council chief executive Pat Dougherty, who has been in the job for two months.
‘‘I don’t think we have a policy about our coastal areas at all ... we can’t do something in The Glen, and then tell Monaco ‘no’ or vice versa. And if we’re doing it there, what does that mean for other lowlying areas of Nelson, or areas of exposed coastline?’’
‘‘We could spend some money today, and in fifteen years’ time it gets ripped out by rising sea level and bigger waves. There is nothing harder than trying to stop the sea, rivers are a simple job by comparison,’’ Dougherty said.
He described February 1 as ‘‘one out-of-the-box’’.
‘‘But in twenty, thirty years’ time, it won’t be as unusual as that. We have to look at all our infrastructure and decide is it in the right place.’’
Dougherty referred to the failure of sewerage pump stations, flooded during the storm, which led to contamination in the Waimea Estuary and Nelson Haven.
‘‘Do we move those pump stations, do we raise them ... there’s millions of dollars just in there straight away. And if we move the pump stations away, what happens to the houses that they serve, that are also lowlying.’’
‘‘What we’re waiting for is for MFE [the Ministry for the Environment] to come out with some clear guidelines about what local government should plan for, because one thing we don’t want to do is find that we’re planning for something and the rest of New Zealand is planning for something else.’’
Reese said discussion needed to continue with the Government about how to pay to help protect public assets. ‘‘There are not three years now to do nothing ... we’ve got to get on with it.’’