OPINION: Autumn weather is invariably fickle. For residents and business owners hit by the devastating rain bomb which struck in and around Richmond on Sunday it's a fickleness taken to extremes. To think that just a week or two back we were facing a serious drought.
While the cost from Sunday is still being tallied and details collated, for those in the strike zone the impact appears as great as in the previous rogue rain event in the region, in December 2011.
As is usual when we are tested by disaster, there have been numerous incidents of people - whether neighbours or shop owners, paid emergency workers or volunteers - pitching in to help others.
Two things surprised most about Sunday's storm: its sudden ferocity and its localised nature. More than 100 millimetres of rain fell on central Richmond in just one hour - that's a scarcely believable volume, representing nearly one-third of Nelson's total for the entire first quarter of this year. Motorists driving from Richmond late Sunday afternoon or early evening faced a wall of water which (should have) forced them to slow to almost a crawl; by the airport roundabout they could have turned off their wipers.
Tasman Mayor Richard Kempthorne's early estimation was that the amount of flood and water damage to homes exceeded the 2011 devastation. That's a big call. Then, insurance claims totalled $20 million, although not only for houses.
Hopefully, the cost of this week's chaos will not get close to that amount though, as usual when nature lets rip, there will be a few people very heavily hit, but most of us emerging comparatively unscathed.
The 2011 rainfall was rated as a once-in-500-years event in some part of the region, such was its devastating force. Now, 16 months later, we have had another weather bomb, and the force with which it hit central Richmond has been described as unprecedented. By rights, we should be spared further flooding for some 1000 years, although climate scientists might pour cold water on that theory.
Although some sceptics continue to deny that there is anything unusual or untoward happening, the evidence, whether anecdotal or scientific, is that the frequency and ferocity of extreme weather events is growing, along with other symptoms of growing change.
Mainstream science is currently of the opinion that the Earth's climate system is unequivocally warming, and it is more than 90 per cent certain that humans are causing most of this change through activities that increase concentrations of greenhouse gases in the atmosphere.
Regardless of that, there is little that our councils can do to prepare for a deluge as heavy as that which struck Richmond on Sunday, or across the region's coastline in December 2011 for that matter.
Culverts, no matter how well designed, can only cope with so much, and so emergency workers, council contractors and neighbours once again found facing a major mop-up.
Three good things: the rain bombs have struck different targets this year compared with 2011, the drought is a distant memory and our civil defence system is getting plenty of practice.
- The Nelson Mail