@ajsadauskas @sydney OOOOHHH! 200 mm? We had between 200-370 mm in one day years ago in Florida. Has happened more than once here and elsewhere in the world. Lots of flooding. Ponds and streams refilled.
this post was submitted on 03 Apr 2024
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I guess it all depends where it's falling. 200mm might be nothing in a tropical climate during monsoon season, but catastrophic in a desert climate.
Good luck with your wet willy willys over in Florida.
@No1 Very true and depends on over how long of a period of time. 25-80 mm in a matter of 20-30 minutes isn't so great anywhere, much like 400-600+ mm over a two day period.
@ajsadauskas @sydney Same thing has applied to parts of California and the US, Canada, Europe, Asia. Then the weather patterns will change again and the excessive precipitation will be in other areas whilst some get dryer. History repeats itself time and time again. When you over 40 or 50 you'll realize it more and more then shrug it off as most of us who are older do.
The really odd thing is that we're supposed to be in an El Niño phase, which should mean South America gets a lot of rainfall, but that it's very dry here in the western Pacific. Instead we've ended up with a year just as wet as during the last La Niña event.
Hmm. 50-150 mm tomorrow for us, up to 50 today and up to 50 Saturday.
We're on a hill so lucky ducks but last time we got 10% of the year's rain in a day quite a lot of trees up and died.
@naevaTheRat @ajsadauskas Plant some casuarina trees. They don't mind wet feet and are drought tolerant. Added bonus they make spooky whoosing sounds during storms.
got powerlines over the property so height limited. Probs not a terrible idea though if we can find dwarf cultivars. The flowering natives tend to be a bit sensitive to wet feet (although the teattrees do great)
I think it's easy to forget how much rain there had already been before the last big floods. I don't think anywhere on the east coast has had anywhere near as much rain this year so far. I can't see an event like this having the same impact. We'll see I guess.
I dunno about down south, but here in Brisbane it's at least felt pretty similar. We've had weeks of on and off miserable rainy weather.
Personally I don't feel too worried, because where I live the biggest concern is the Brisbane River flooding, not creeks or overland flow. And with the Wivenhoe Dam at just 80% (100% only means maximum usable for drinking water, it can store over 200% during flood events), it'll take a lot more before flooding is likely here.
I'm not certain of Brisbane, but my family has a little farm about 4 hours north of Sydney. Part of it is floodplains (go under in even small floods) so we tend to be reasonably familiar with the conditions that cause the big floods.
At the moment it's not desperately dry, but the soil can hold a lot more water and there hasn't been enough rain to cause run off so the dams are almost empty.
There's a bit of a downpour now and if it's particularly long and intense there may be a small flood round there, but nothing like the conditions surrounding those devastating floods last year.
Also for a lot of those rivers an occasional small flood is healthy because it helps to clear out the excess water weed that may be building up etc.
@maniacalmanicmania Really hope you're right.
That being said, the pessimist in me thinks we're just at the start of Autumn.
If there's already heavy rains at the start of April, then what's going to happen in May, June, July, August, and September?
It's also the same communities that are likely to be impacted — places like Richmond, Lismore, and the towns along the Hawkesbury.
The cleanup and rebuild is still ongoing from last time. Another round of floods would be the final straw — financially and emotionally — for many people and small businesses in those regions.
And if there's two bad flood seasons in two years, no insurer is going to touch those towns.
Hopefully it doesn't come to that.
But another bad flood season would not just be devastatingly bad. It would be "state government seriously considers relocating entire towns to higher ground" bad.
relocating entire towns to higher ground
I've sometimes wondered about that. Sure the costs would be big, but it might pay off in the long run.
Bahahhahahhaa, who am I kidding? What politician or party cares about the long run. They don't care about anything but the next election.
@No1 It's not unprecedented.
A few years ago, after a particularly bad flood, the entire town of Grantham in Queensland was relocated to higher ground: https://www.brisbanetimes.com.au/national/queensland/grantham-reborn-meet-the-little-queensland-town-that-moved-20200227-p5450g.html
If you have a town that's in a floodplain, instead of constantly needing to rebuild it every couple of decades (or less) because of floods, it can make sense to do so.
Banks and insurers look at the risk profile, and then adjust the cost of borrowing or insurance premiums accordingly.
At a certain point, it becomes far cheaper to just call in the bulldozers and rebuild elsewhere.