Just depends on how much water they let out in the Brisbane Valley Dam system this afternoon,I would say that one property we control will go under maybe up too the floor,as the water is already 75mm in the front yard,the only problem with that one is once the creek breaks it's banks and backs up it just floods about 40 houses..
Speculating? 2010 floods?
- Thread starter topcropper
- Start date
Raining pretty solid here in Northern Rivers at present and predicted to continue till at least Sunday. Can't remember having a wet Xmas for ages - normally it's Easter that we get hit every year.
I was extremely lucky to have a dry day to get my house posts in yesterday after bailing out my footings from the previous nights rain
Have a safe one,
I was extremely lucky to have a dry day to get my house posts in yesterday after bailing out my footings from the previous nights rain
Have a safe one,
The GFS models just keep getting worse and worse for south east QLD and the northern tip of NSW. I sure hope they are wrong.
I've nearly finished wheat harvest. Just some bog holes and scraps to go. The models are saying the flooding is going to stay above me.
See ya's.
I've nearly finished wheat harvest. Just some bog holes and scraps to go. The models are saying the flooding is going to stay above me.
See ya's.
Wivenhoe?
At what capacity is Wivenhoe dam full for total flood mitigation? The level at which no more water can be held back? Is it 74 metres?
Looks to be at 71 metres and rising rapidly.
http://www.bom.gov.au/fwo/IDQ65389/IDQ65389.540177.plt.shtml
It was sort of ironic last night on the flood relief TV show on channel 9.
No one wanted to mention the 100's of mills falling in the catchments upstream.
Good luck all.
Any flood reports people? Pictures? Sorry, I'm a weather nut, OK.
See ya's.
At what capacity is Wivenhoe dam full for total flood mitigation? The level at which no more water can be held back? Is it 74 metres?
Looks to be at 71 metres and rising rapidly.
http://www.bom.gov.au/fwo/IDQ65389/IDQ65389.540177.plt.shtml
It was sort of ironic last night on the flood relief TV show on channel 9.
No one wanted to mention the 100's of mills falling in the catchments upstream.
Good luck all.
Any flood reports people? Pictures? Sorry, I'm a weather nut, OK.
See ya's.
Hmm. I think Wivenhoe is full at 74 metres. It seems to me that it will not hold back anymore water by this afternoon?
Why is there not much warnings from the authorities about what's going on?
Or are my figures all ballsed up?
See ya's.
Why is there not much warnings from the authorities about what's going on?
Or are my figures all ballsed up?
See ya's.
This might be the test for the Wivenhoe Dam,from what i'm told it can hold 200%,and it's above 150% now so from the rain still on the way downHmm. I think Wivenhoe is full at 74 metres. It seems to me that it will not hold back anymore water by this afternoon?
Why is there not much warnings from the authorities about what's going on?
Or are my figures all ballsed up?
See ya's.
then they will have to open all the the high volume flow outlets,, then depending on the high tides the low areas in Brisbane will flood..
from the SEQ Website today
Full Supply Capacity:1,165,238 ML
Current Capacity:1,728,590 ML (100.0% full) at 10/01/2011 09:00AM
Flood Mitigation:1,450,000 ML
So it can hold 2,615,237ML and it is currently holding 1,728,590ML so there is 886,645ML spare capacity at present. What it doesnt tell you is the speed of the current inflows and so when that capacity will be used up
Also checking Lake somerset that flows into Wivenhoe
Full Supply Capacity:379,849 ML
Current Capacity:587,437 ML (100.0% full) at 10/01/2011 09:00AM
Flood Mitigation:155,000ML above full capacity, totalling 524,000ML
So Lake Somerset is over full by 63,437ml
And North Pine - Doesnt join Wivenhoe but will need releases
Full Supply Capacity:214,302 ML
Current Capacity:222,685 ML (100.0% full) at 10/01/2011 09:00AM
Flood Mitigation:No
So North Pine is 8,383ML over full
Full Supply Capacity:1,165,238 ML
Current Capacity:1,728,590 ML (100.0% full) at 10/01/2011 09:00AM
Flood Mitigation:1,450,000 ML
So it can hold 2,615,237ML and it is currently holding 1,728,590ML so there is 886,645ML spare capacity at present. What it doesnt tell you is the speed of the current inflows and so when that capacity will be used up
Also checking Lake somerset that flows into Wivenhoe
Full Supply Capacity:379,849 ML
Current Capacity:587,437 ML (100.0% full) at 10/01/2011 09:00AM
Flood Mitigation:155,000ML above full capacity, totalling 524,000ML
So Lake Somerset is over full by 63,437ml
And North Pine - Doesnt join Wivenhoe but will need releases
Full Supply Capacity:214,302 ML
Current Capacity:222,685 ML (100.0% full) at 10/01/2011 09:00AM
Flood Mitigation:No
So North Pine is 8,383ML over full
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*whistles*
i've been online to see what all the 'fuss' is about - and geeeezzus you guys got it bad!
i don't watch the news so when a story sticks around for 3 weeks i eventually take notice.
how is that much water even possible?
is the Murray Basin looking set to fill up from this?
i've been online to see what all the 'fuss' is about - and geeeezzus you guys got it bad!
i don't watch the news so when a story sticks around for 3 weeks i eventually take notice.
how is that much water even possible?
is the Murray Basin looking set to fill up from this?
Took the kayak down kedron brook on the weekend (no not me in courier mail). Good fun stuff. probably safer at the moment than usual as the normal obstacles are so covered with water that we just go a foot or so over the top of them. right now we could use it for one of our adventure races! Never thought that would be possible.
Just waiting for the mildew to start. Spent the weekend running around like a madwoman any time it stopped/started raining opening and closing windows.
Almost saw blue sky around 3:30pm out of the office (CBD) window.
Our backyard is soaked through - we're higher than the two yards beside us but slightly down slope from the house behind us - usually the water drains pretty well - however I'm heading out to put in a new ag pipe drain down the side of the retaining wall to prevent any more flooding of the garage. At least we're on the high side of the street.
(no not me in courier mail). Good fun stuff. probably safer at the moment than usual as the normal obstacles are so covered with water that we just go a foot or so over the top of them. right now we could use it for one of our adventure races! Never thought that would be possible. Just waiting for the mildew to start. Spent the weekend running around like a madwoman any time it stopped/started raining opening and closing windows.
Almost saw blue sky around 3:30pm out of the office (CBD) window.
Our backyard is soaked through - we're higher than the two yards beside us but slightly down slope from the house behind us - usually the water drains pretty well - however I'm heading out to put in a new ag pipe drain down the side of the retaining wall to prevent any more flooding of the garage. At least we're on the high side of the street.
Hmm. I think Wivenhoe is full at 74 metres. It seems to me that it will not hold back anymore water by this afternoon?
Why is there not much warnings from the authorities about what's going on?
Or are my figures all ballsed up?
See ya's.
I wouldn't like to be the bloke running SEQ water and in charge of water releases from wivenhoe. I'll say that it looks like it was all a bit of a balls up.
The poor buggers were only doing their best, and they probably had strict rules to adhere to, but the figures look to me as though they didn't release anywhere near enough water over the weekend before the flood peak, and then by Monday arvo when the crap hit the fan in Toowoomba and down the Lockyer valley and over the rest of the catchment of wivenhoe, there was no storage left. So right at the peak, the releases from wivenhoe were just the same or even a fraction higher than inflows, meaning that the dam made no difference to water heights at all.
OK. It would be nice to have a crystal ball and know what to do. I'd say wivenhoe stopped a heap of minor flooding to rural roads and catchments in the days leading up to the peak, but made no difference to the total peak on the Thursday in Brisbane. Very disappointing.
In hindsite, the dam needed to have the full flood mitigation capacity when the cataclismic rain event hit on Monday arvo. But it didn't. It had way too much storage used up.
Lets see what the investigation finds?
What are the ramifications if it turns out wivenhoe made no difference, or even made things worse?
See ya's.
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Rainfall in Wivenhoe catchment higher than 1974 yet flood lower. Evidence is that Wivenhoe certainly lessened the height of the flood. Unknown quantities of water from Lockyer Creek (below Wivenhoe dam) where the water gauges were at record heights before being washed away, also from the Bremer River.
Trouble is, Wivenhoe Dam was built as flood mitigation. The plan included the Wolfdene dam (south of Brisbane) for water supply. Goss Government reneged on Wolfdene, hence the Wivenhoe Dam taking the unplanned dual roles of water supply and flood mitigation, by nature a conflict of interests.
Investigations will be interesting - let's watch the politicians ducking for cover.....
Marg
Trouble is, Wivenhoe Dam was built as flood mitigation. The plan included the Wolfdene dam (south of Brisbane) for water supply. Goss Government reneged on Wolfdene, hence the Wivenhoe Dam taking the unplanned dual roles of water supply and flood mitigation, by nature a conflict of interests.
Investigations will be interesting - let's watch the politicians ducking for cover.....
Marg
Hard to compare floods. Rainfalls were higher and lower depending on where your comparing. This flood had rainfall coming from the further reaches of the catchment, whereas 74 had heavier rainfalls more locally. There were isolated rainfalls in 74 that were much much higher than anything this time. Also, In 74 there was a storm surge blocking the Brisbane river from entering the bay, caused by the cyclone. This added a metre or so to the heights in Brisbane.
The evidence I see is that wivenhoe was releasing 8000 tonnes per second of water roughly 36 hours before the peak at Brisbane. The peak in Brisbane was not much more than this in total, so wivenhoe releases contributed most of the water at the peak. They had no choice of course, as the dam was full and was in danger of setting off an uncontrolled release.
In hindsite, if wivenhoe had of had 100% storage capacity left for when the main storm hit, the peak would have been lower. This would have ment the floods were bigger in the days before the peak. But surely the main aim is the lowest total peak, to flood the least houses in Brisbane and cause the least damage?
I still reckon it was a balls up. A dam built 30 years ago to stop Brisbane from flooding? Waits patiently for 30 years to be used. It's flood mitigation capacity is 100% full right as it is really needed because it was allowed to fill in the days before the peak to stop minor flooding rather then being kept for the 'big one'.
I made a comment on this thread, the 10th, Monday morning, just hours before the Lockyer disaster happened, where I was surprised at how full the dam was in the lead up, in posts above. And rainfall totals of many 100's of mills were still being forecast for the coming days.
Perhaps the rules need to be looked at as to how wivenhoe is operated.
See ya's.
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I've heard that claim too. So I've looked into it. I reckon it's wrong. There was more rain in 74.
In the 5 days between the 24th and 29th of January, 1974, there was between 500 and 900 mills over the entire Brisbane city area, with an official recording of 650 mills in the CBD. The rainfall figures for the earlier part of Jan, and the last part of 73, were just as wet as this year too. The Gold Coast was also totally flooded. I know, as I was there!
There was totals in those 5 days of, 1318 mills at mt Glorious, including 500 mills in 24 hours, and 819 mills at New Beth.
The total official rainfall for Brisbane this month so far is 315 mills. Some of the best falls in the catchment I can find for the total month so far are mt Glorious, 760 mills, Lowood, 642 mills [how'd Brenda go?], and Esk, 478 mills.
I reckon the figures show that 74 was wetter.
See ya's.
Yeah, OK, that's obvious. I've been talking about the flooding in Brisbane, and the entire catchment, including the wivenhoe catchment, not just wivenhoe dam. So I assumed you were too?
See ya's.
See ya's.
