Queensland Floods

This is something that's been playing on my mind a lot over the last few days. The latest figure I've heard is 61 missing and I have little hope that they'll be found safe and sound.


Apparantly police and locals in Grantham are already saying they believe to total death toll in that town alone will be around 40. That's a town of 350 people.
 
I first moved to Toowoomba in 1975 and I've lived there off and on ever since and have never seen anything like what's been occurring this week.

Murphy's Creek is just one example of something you would never credit happening. The headwaters of the creek are on the escarpment at Ballard, on the outskirts of Toowoomba, and from there to where the houses have been washed away is only a distance of about 5 kilometres or so. It's hard to believe that such a small catchment could generate such a volume of water.


I think part of what contributed to it is the "supersaturation" of the ground. We've had so much rain that any additional precipitation immediately runs off, and there was *a lot* of rain on Monday. Check out this image from NASA. (shows rainfall on Monday)
 
Goondiwindi is currently the area of most concern in Queensland. This is where the water from the Toowoomba flood actually went.


Are you sure about that? I thought that water went into the Lockyer Valley (N and E). Goondiwindi (S and W) seems to be threatened by the McIntyre River which doesn't appear to feed out of Toowoomba - in fact it looks to me like there's some low hills between the two places.


I've made a slight blunder, but I've got the directions more-or-less right.

East and West Creeks in Toowoomba (responsible for the flash flood in the City) join up to form Gowrie Creek which flows West to join the Condamine River, which in turn becomes the Balonne River which flows through places like St George and Dirranbandi. These places will definitely experience more flooding as a result of the Toowoomba event.

The Macintyre River, which runs through Goondiwindi, and its major tributary, the Dumaresq (pronounced 'due-merrick') River both rise in northern New South Wales in the area of Glenn Innes/Guyra.

Apologies for this boo-boo, and thanks for querying my assertion. That'll learn me.

My main point, however, remains. The creeks flowing through the City of Toowoomba most definitely flow West and eventually form part of the Darling River, ultimately finding their way to the sea at Lake Alexandrina in South Australia.
 
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I think part of what contributed to it is the "supersaturation" of the ground. We've had so much rain that any additional precipitation immediately runs off, and there was *a lot* of rain on Monday. Check out this image from NASA. (shows rainfall on Monday)


That's absolutely amazing. Nobody could possibly have predicted that.

Are you and yours safe, Magenta? Please forgive me for not asking sooner.
 
That's absolutely amazing. Nobody could possibly have predicted that.


It is amazing. But we likely will see more extreme events, both wet and dry, if my understanding of climate change is correct.

Are you and yours safe, Magenta?


I'm fine, I live a long way from the Brisbane River in the south-eastern bayside. My biggest concern at the moment is how I'm going to push the mower through the huge amount of growth that's occurred since it was last dry enough to mow!

Please forgive me for not asking sooner.


No worries, I wouldn't have been posting if I was having difficulties. :)
 
I'm fine, I live a long way from the Brisbane River in the south-eastern bayside. My biggest concern at the moment is how I'm going to push the mower through the huge amount of growth that's occurred since it was last dry enough to mow!


You aren't alone in that, it seems. My daughter in Toowoomba posted this on fakebook yesterday:


Rachel is having a day of very mixed emotions today. Went into Toowoomba's city to have a look & bawled my eyes out (yep, right in the middle of town). Still in disbelief that this could even happen here, but it's sinking in. Now laughing out loud as the sound of 1000 lawn mowers fills the air all around Toowoomba as people take advantage of the break in the rain to get their lawns cut.
 
[qimg]http://www.yvonneclaireadams.com/HostedStuff/WeatherRadarVictoria_14Jan2011.jpg[/qimg]
This won't end well

Sure it will, if the goal is to fill Lake Eildon or wash all the crap out of the Yarra.

It's been raining for most of the last 3 days here in Diamo, and I give us a 5% chance of playing cricket tomorrow even if it stops raining today it's so sodden here. Luckily with the water management program we put in 2 years ago it's harder to flood the Diamond Creek now, but if it keeps going like this it might flood anyway.
 
I've made a slight blunder, but I've got the directions more-or-less right.

East and West Creeks in Toowoomba (responsible for the flash flood in the City) join up to form Gowrie Creek which flows West to join the Condamine River, which in turn becomes the Balonne River which flows through places like St George and Dirranbandi. These places will definitely experience more flooding as a result of the Toowoomba event.

The Macintyre River, which runs through Goondiwindi, and its major tributary, the Dumaresq (pronounced 'due-merrick') River both rise in northern New South Wales in the area of Glenn Innes/Guyra.

Apologies for this boo-boo, and thanks for querying my assertion. That'll learn me.

My main point, however, remains. The creeks flowing through the City of Toowoomba most definitely flow West and eventually form part of the Darling River, ultimately finding their way to the sea at Lake Alexandrina in South Australia.


The floods have been a bit of a geography lesson. I've been trying to find online maps of the different catchment areas. This map has good detail of the Lockyer/Bremer/Brisbane catchment area.

I haven't yet found anything with useful detail for the Condamine/Balonne area, and this map of the Macintyre/Dumaresq system shows everything stopping at the Qld/NSW border.
 
The floods have been a bit of a geography lesson. I've been trying to find online maps of the different catchment areas. This map has good detail of the Lockyer/Bremer/Brisbane catchment area.

I haven't yet found anything with useful detail for the Condamine/Balonne area, and this map of the Macintyre/Dumaresq system shows everything stopping at the Qld/NSW border.

They're water managment plans and probably aren't entirely useful for determining the flow of water as humans have a habit of drawing lines arbitrarily. Some of the main waterways on those maps quite clearly pass through "catchment" borders.

Strictly speaking the correct geographic term is a drainage basin (sometimes called a catchment), and by definition water cannot pass across the border between two drainage basins (although it can flow out of the sub-basin of one system into the wider parent drainage basin).

Having said that you're right that it's a useful geography lesson! For example I was confused because all of the media has been talking of the water from Toowoomba heading east into the Lockyer Valley and causing chaos there, while Akhenaten tells us the main creeks (which were so often shown in flood) drain west.

Now I begin to make sense of it. Toowoomba is literally at the crest of a watershed, with the majority of the city (and the CBD) on the western side. Most of the dramatic footage we've seen from Toowoomba was thus water draining west, into the Murray-Darling Basin.

However, the storm front came from the NE, and thus in addition to the dramatic pictures we saw, the majority of rainfall would have actually been on the eastern flank of the watershed which would have had less impact on Toowoomba, but would have drained east into the Brisbane River Basin, passing through the Lockyer Valley enroute.

Thus while the media is true in saying the water from Toowoomba went on to hit the Lockyer Valley, Akhenaten is right in that the specific water the media was showing you, was actually going in the opposite direction.

It all makes sense now. :D
 


Thank you!

Having said that you're right that it's a useful geography lesson! For example I was confused because all of the media has been talking of the water from Toowoomba heading east into the Lockyer Valley and causing chaos there, while Akhenaten tells us the main creeks (which were so often shown in flood) drain west.

Now I begin to make sense of it. Toowoomba is literally at the crest of a watershed, with the majority of the city (and the CBD) on the western side. Most of the dramatic footage we've seen from Toowoomba was thus water draining west, into the Murray-Darling Basin.

However, the storm front came from the NE, and thus in addition to the dramatic pictures we saw, the majority of rainfall would have actually been on the eastern flank of the watershed which would have had less impact on Toowoomba, but would have drained east into the Brisbane River Basin, passing through the Lockyer Valley enroute.

Thus while the media is true in saying the water from Toowoomba went on to hit the Lockyer Valley, Akhenaten is right in that the specific water the media was showing you, was actually going in the opposite direction.

It all makes sense now. :D


There's nothing like a flash flood to focus your attention on where water flows after it falls!

The images from Toowoomba and the Lockyer Valley are the stuff of nightmares actually. As bad as the river flooding has been, at least it's fairly steady and predictable.

Main Road Research, in North-East Melbourne is flooded.


Time for a Victorian floods thread?
 
Thus while the media is true in saying the water from Toowoomba went on to hit the Lockyer Valley, Akhenaten is right in that the specific water the media was showing you, was actually going in the opposite direction.

It all makes sense now. :D


Jeebus. Me and the media both correct on the same day! There's a first.
 
I've been watching footage like this:

http://www.youtube.com/watch?v=qlt_5ZQkans

And keep thinking that someone is going to have to explain just why people were not warned sooner about the risk from runaway boats and/or pontoons.

Assuming they don't sink, some of those boats could end up in New Zealand!
 
I've been watching footage like this:

http://www.youtube.com/watch?v=qlt_5ZQkans

And keep thinking that someone is going to have to explain just why people were not warned sooner about the risk from runaway boats and/or pontoons.

Assuming they don't sink, some of those boats could end up in New Zealand!

Most of them will probably run into North Stradbroke Island.
 

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