Page 15.
Queensland
water sources read “Although we
have mainly used climate-dependent surface and ground water sources in the past,
we need to consider alternative water supplies such as recycled water,
stormwater and desalinated water."
Page 14. The
graph under the heading “the water
cycle” reads “Adapted from
recycled water in
Australia
”. It includes “Recycled water plant” and “Desalination plant”
There they are shaping
our water future. They are there because former Premier Bligh was correct on the
demise of the Traveston Dam, the only storage of consequence attempted. "Look forward to a future of desalination and
recycled water plus harsh water restrictions".
***
In a
30 year water plan there are no other alternatives of a scale to keep pace with
rising water needs.
There
are no applications that will eliminate flooding in Brisbane and mitigate
flooding in Ipswich and Gympie.
##############
The way
forward
However, the
integration of the Borumba dam expanded to a capacity larger than the joint
capacity of the Wivenhoe/Somerset can resolve these matters
At a saving of $3.1 billion, we can flood
proof Brisbane (thought impossible by Premier Newman and Lord Mayor Quirk), mitigate flooding in Ipswich with four of the last five floods
kept below the damaging 14 metre mark, mitigate flooding in Gympie by damming the
Borumba hard rock catchment which is within the Gympie catchment. Provide natural water to pass the much longer
catchment periods than drought being 11 years
##############
Progress with Seqwater in the
examination of our plan.
On the 13th January 2013 the Courier/Sunday Mail
published our plan in simplified form. It may be still held on line at the above
link to the Courier Mail.
Even before we started they had this to say
“We seek to
ensure infrastructure is not augmented before it is needed”. It seems
a reasonable methodical approach. It is this approach that got us into big and
costly trouble in the past and will do the same in the future if it is not
recognized. (Seqwater initial letter) E.G. Prolonged drought known as
"uncommon events" and flooding do not lend themselves to this approach
in fact in recent times we have seen us damaged by several billion dollars.
This is the demand
management instituted by Minister Casey on the cancellation of the Wolfdene
Dam in 1990. It screwed up well laid plans for future use by this method by the
dam cancellation. Our plan is to reinstall that dam with the expanded Borumba
Dam.
They also declined to
consider the Borumba expansion for at least another 6 years. Even then they
said it would be subject to robust discussion. That dam expanded is central to
the natural water needs of SEQ for the next 50 years.
So we see that even
before we have reached the conference table they have laid down their positions
which demonstrates to me that they have little grasp of how our water supply
works and what additional benefits can accrue or they are reading off prior
information. There were many editions of the prior "South East Queensland
Water Strategy". This flows through to Minister
McArdle and his advisors who draft his letters.
Our understanding at
the meeting with Minister McArdle and Seqwater was that our plan would be
examined "as it is" to see if it works and then for Seqwater to
re-examine their position on integration. They have reversed this procedure with
two major blocks exposed as briefly outlined above. The blocks are movable and
should be removed.
We hold a reasonable
financial hand in the development such as inclusion in the LNP national 100 dam
plan. This was the result of our efforts. We have pointed out the error in the
allocation of the Wivenhoe/Somerset water at a saving of $210 million annually.
The damage caused by a large floods is in the $billions.
Recently they
considered a "workshop". We consider that the plan's Hydrology has
been proven by events. Engineering of the project requires a one on one with a
Government engineer. Then a "workshop" could be of value.
#############
Flood proofing Brisbane proven by the
February 2013 flood
The flood of 2013 had important milestones that confirm my calculations below.
Bremer and Lockyer
There was no flooding in Brisbane of any
habitable premises (Lord Mayor Quirk).
There was no flooding in Ipswich. Mayor Paul
Pisasale.
I seem to be the only one that was not surprised by the
outcome.
The Wivenhoe Dam had sufficient room to hold back all water
above the dam and as a consequence, we saw the effect of a full blown Bremer
River and Lockyer Creek running free.
It is the foundation of this website, when viewing flooding,
that the Bremer River and Lockyer Creek, on past information, does not have the
volume to flood Brisbane and damage Ipswich. In Ipswich, most of the block
caused by the Wivenhoe at the Bremer entrance is removed.
Move to review Bremer
and Lockyer
###################
* To move direct to Flood Proofing Brisbane. Mitigation in Ipswich and Gympie. CLICK
HERE
* To move direct to Drought Proofing South East
Queensland
CLICK
HERE
*
To view the Borumba Dam expansion, an integral part. CLICK HERE
to view channel 10 review of Borumba Dam
***************************************************
A brief overview of our water supply
Natural water
Since the completion of the Wivenhoe Dam in 1986, in the
period 1986 to 2001
we 
witnessed
the dam filling by 1988 and a further 4 refills in 1992, 1996, 1999 and a top-up
in 2000. It takes "low pressure systems" to do this as recognized in
this graph by its "factory roof type" in its dam levels. In that 12 years,
we had plenty of water or so we thought.
In the second 12 years 2001 to 2012 we witnessed a
"drought" or so we thought and
followed by the flood of January 2011. The flood was no surprise to me having
observed the operations of nature and the dams to the point that I backed my
observations up by warnings to Premier Bligh and Minister Hinchliffe in 2008 and
2009. Read more
Manufactured water
Desalination : The Tugun plant
would take 26 years to 2038 to fill the Wivenhoe dam if no water is taken out.
35 years to year 2047 if the Somerset is included.
Recycled water : Using reports of
former Premier Bligh, recycled water is the same volume.
Between them they can only supply
31 per cent of our present requirements.
This means very heavy water restrictions on reaching 40% level in our dams.
Much better way
Much better way: There is a much
better way to eliminate flooding in Brisbane, mitigate flooding in Ipswich and
Gympie, put real meaning into "drought" proofing Brisbane and reduce
water price permanently. That
is what this website is all about.
So we have seen it all in a practical
way in our lifetime. However we have not learnt from this and the LNP appears to be
following the same path.
Residents of South East Queensland
deserve better than a second clumsy go at securing our water supply which
will be again at a high cost.
Post Election/Flood Inquiry - period
With election out of the way and the final flood report tabled
there are some clear issues emerging.
1. Our Wivenhoe/Somerset dams are too small to deal with the conundrum
of "Drought" and "Flood".
2. The Flood Inquiry was blocked from examining new dams or the expansion of
existing dams on page 438 of its report.
3. This coordinated with the version of the South East Queensland Water Strategy
that relied solely on desalination and recycled water after the Traveston dam
proposal was cancelled.
4. There was overwhelming support in submissions to expand the dams.
5. The LNP is averse to using desalination and recycled water. (this was
their position before the election. It has to be clarified by the LNP as this
may not be their current position).
6. There are two options to increase the capacity of the dams. Raise the
Wivenhoe Dam wall or expand the Borumba Dam to a capacity greater than the
Wivenhoe/Somerset and integrate it into the Wivenhoe/Somerset system by way of
efficient two-way pipeline.
7. The cost of water is substantially reduced by either proposal, however the
Borumba has the ability to more than double the water available and as a
consequence greater flexibility in both drought and flood.
The current block to the system (point
6) that needs
to be rectified. Points 8 to 13 cover point 6 Click
hereto view these points
We cannot go forward unless we assess what went wrong in the past.
* What went wrong with our water supply?
* Serious errors of judgment of those in charge.
Click for index
------------
* Flood proofing Brisbane and Ipswich and mitigating flooding in Gympie.
Providing a superior and less costly water supply than desalination and recycled
water and putting real meaning into "drought
proofing" SEQ.
Click for full index
**************************************************
What went wrong with our water supply?
What went wrong with our water supply that caused those in charge to miss-spend
the best part of 7,000 million
dollars for a third class system that will not do the job intended?
How could we
not foresee from past experience the inevitability of extended "drought" like periods
and major floods in South East Queensland?
Premier Beattie sitting on a stump in the depleted
Wivenhoe Dam. (Click to expand)
He failed to realise what was happening around him was
something other than a "drought" with consequences that can be much more severe than any drought. The
natural and random occurrence of our main
water supply has such a variation from top to bottom that on the opposite end it would have had
Premier Beattie sitting in a small boat in the Jindalee area or other parts of
flooded Brisbane five years later.
The bottom end is limited by the capacity of our dams whereas
the top end is unlimited. A volume equivalent to two and one-half times the
capacity of the Wivenhoe went over the dam wall in January 2011. We examine the
random and extensive nature of our main water supply events in the next heading.
His successor Premier Bligh also displayed this lack of
understanding. I warned her of it on the 18th January 2008 followed by a warning
to then Water Minister Hinchliffe on the 23rd April 2009. The warning was the
mathematical certainty that our dams would refill and overflow. Read more
Our water supply
Every
person in South East Queensland now realises that our
dams are not filled by storms that provided only 3% in the last 6
months and not by General rain which provides only moderate fills, the
largest in the life of the Wivenhoe being 15.6% in the middle of so-called drought. One
can see the small bump in 2003/04 on this dam level chart. Read
more
SEQWater dam level chart 1990-2007 : click to expand
The red lines on this dam level chart emphasise the clear
statement of Mr Rob 
Drury, dam controller, of SEQWater who pointed out in his
article in the Courier mail Feb 2007 that it took large events to fill these
large dams. He called them "uncommon events".
It confirms Dorothea McKellar's OBE poem of the early nineteen
hundreds that there is a big difference between
"rain" and "flooding rain". They show two things:
SEQWater Courier
Mail article Feb 2007: Click to expand
1.
Ordinary summer rainfall and storms were inadequate for our
needs from the starting point of the Wivenhoe Dam. It takes concentrated rain
("flooding rain") as 300mm in a few days is a flood capable of filling the dams from scratch
whereas 3 months of 100m each month is just a trickle.
2. The "uncommon events do not come every year". They
average 3.7 years with most below that average. This means that those above the average
can extend for up to 11 years which is well beyond the longest known
drought being the 5 year Federation drought 1898 to 1903.
They are more prevalent than the chart indicates as many do not come west enough
to cover the catchments.
The volumes that are supplied by "uncommon events"
vary from 20% to 285%. We have now all seen four of these "uncommon
events" refill the dams from 18%. Overflows then occurred with 26% in October 2011
followed by December with 24% and finally January with overflow of 285%.
Combination of flood heights, Bureau flood
information and rainfall. Click to expand picture.
******************
Review of serious errors of judgment will give
us further insight on how to deal with Flooding and putting real meaning into
"drought proofing". This is not a political statement. It should be
kept in mind that the dams were under the control of the Labor Party for
the life of the Wivenhoe (1989-2012) of 23 years except for three years.
Serious errors of judgment
1. Kevin Rudd - Wolffdene Dam
2. Premier Beattie and Deputy A. Bligh's "drought".
3. Premier Beattie and Deputy A. Bligh. - The Traveston dam
4. 1992 to 2001 Those in charge and the Flood Commission.
5. Queensland Climate Change Centre of Excellence
Return to Index foreword
Kevin Rudd - Wolffdene Dam
Wolffdene dam water supply
The
initial error of judgment was made by the Goss Government with his chief of
staff Kevin Rudd. It was supported by the
"rump" Liberal party and was plainly put forward in the Goss election plank.
By 1992 it was obvious from the dam level chart of the
Wivenhoe 
pictured
on our right that our water
supply could not survive without "uncommon events". Assurances were
given at the time of cancellation (Planning had commenced) that further planning would be carried out. If planning was carried out it
was entirely inadequate for "drought" and "flood". Read
official parliamentary statement
Wolffdene dam in flood time
This 2011 flood saw all catchments saturated. There is no
doubt that the Wolffdene dam would have been full well before the January 2011
flood. This would have permitted the
pre-release of water from the Wivenhoe/Somerset sufficient to retain all the
flood waters of the Wivenhoe/Somerset. With the Bremer River and Lockyer creek
running free, there would have been little damage in Brisbane and Ipswich.
Premier Beattie and Deputy A. Bligh's "drought".
Premier
Beattie used the "decile" map extensively to convince us that our low
dam levels were caused by a "drought". Decile maps grade rainfall
from 1 to 10 with "1" the "lowest on record" category. The corresponding
map is a "percentage" map that records the percentage against the long
term average 1961 to 1990.
The rainfall for the period was in decile "1" even
though the rainfall was 80% of the long term average. This is because district
40 in which the dams reside is a stable area and in 6 year lots, (the length of
the so-called drought) never had less than 80% of
the long term average since records were kept. So we are dealing with
a statistical aberration. 80% being in
decile "1" was not normal but was held out by Beattie/Bligh to be
normal and accompanied by an enormous advertising campaign to convince citizens
of SEQ of drought in the catchments.
Bureau of Meteorology rainfall stations in the catchments show
that for the summer periods 2001 to 2006, Wivenhoe had 99.1% of the long term
average and Somerset 91.4%. The 20% reduction was entirely in the non-summer
months that produce little inflow into the dams.
If Premier Bettie had held the "percentage" map
aloft which read 80%, then people would have considered the matter more deeply
and required more explanation and perhaps the right path forward.
Read more
Premier Beattie and Deputy A. Bligh. - The Traveston dam
For citizens of South East Queensland, the choice of the
Traveston over an expanded Borumba Dam to a holding capacity more than the
Wivenhoe/Somerset combined was a monumental and costly blunder.
The public guarantee of Ms Bligh to residents of Gympie
dealing with the Borumba that 
"that would be the way they would go if it stacked 
up" was a sham. Ms
Bligh was writing to grazier Ron McMah to obtain commonality of the terms of
reference so that the Engineering and Hydrology reports could start. Those
reports had
been
completed on Queensland Water Commission (QWC) terms and signed off a week prior to her letter.
Letter Bligh 31/01/07 : Signed Engineering 22/01/07 :
Beattie view ignored by Bligh
The most important feature of the McMah proposal was the
storage of surplus water from the Wivenhoe/Somerset. The catchment of the
Borumba was too small for for such a large dam and we needed more capacity.
Both the Engineers and Hydrologists reported that they had
received "advice" that there was no water available from the
Wivenhoe/Somerset. After meetings with Minister Hinchliffe and later senior
members of DERM, I was provided by the Chief Hydrologist the information
necessary to determine that there was available between 130,000ML and 160,000ML
annually to us that had been diverted to the ecology by a clever, or
alternatively clumsy, manipulation
of a single definition.
The instructions of the Technical Advisory Panel had not been followed
It explained to me why the "yield" of 446,900ML as publically
advised by the 
former SEQWater, not connected to the current Seqwater, being
reduced to 286,000ML, a drop of 160,000ML. (Yield is the volume of water that
can be guaranteed in a year without failure otherwise known as HYNF)
Annual "yield" in public documents of SEQWater
2001. Click
This volume of 160,000ML plus the additional
yield from the expanded Borumba of a further 50,000ML is well above the
110,000ML Traveston proposed by Premier Beattie with the final stage of 40,000ML
well into the future and ephemeral.
With the Traveston cancelled by the cross-check environmental
concerns of the Federal Government that were not picked up by the QWC and the
contractors, Premier Bligh declared that "desalination" was the only
answer.
That decision was seriously deficient and we will examine.
Read more
1992 to 2001 Those in charge and the Flood Commission.
There was no panic or serious observation of how our water
supply works in that period. However there is cause for concern when we apply
their findings on dam reductions to counter flooding.
The Wivenhoe and Somerset dams were designed with flood
compartments that exceed the FSL (drinking water compartments). The Commission
recommends manipulation of these FSL volumes for flood mitigation benefit.
Application of the current 25% reduction in November 1995 would have seen the
dam level fall to 19.7% (44.7 - 25.0) That level
is comparable with the so-called "drought" period
low in 2007 of 18.0%. Application of the 25%
in that period would have seen a negative figure of -7.0%.
The dam controllers do not have the ability to allow the dam level to rise. They
have to await a "low pressure" system to come along. They average 3.7
years since 1841. The dam level graph above tells the story.
There is currently not enough capacity in the dams to deal with this
conundrum.
Queensland Climate Change Centre of Excellence
In
my view this
organisation has presented misleading information in the name of "Climate
Change". They produced this document that has been
picked up in the Queensland Water Commission Water Strategy and now by the
Flood Inquiry in its interim report. There are fundamental major errors in it
and it should be withdrawn.
They may be viewed in QCCCE
A review of carbon dioxide tax can also be viewed click
here
One example of predictions is by well known Mr Tim
Flannery now chairman of the Federal Government Climate Change organisation. He
was on the original Board of the QCCCE in 2007. As reported in the "Herald
Sun" "In 2007, Flannery predicted cities such as Brisbane would never
again have dam-filling rains, as global warming had caused "a 20 percent
decrease in rainfall in some areas" etc."
The Herald goes on to say that premier Beattie took the
prediction seriously leading to desalination.
The prediction was badly astray with serious consequences.
Since 2007 the Major dams of Wivenhoe/Somerset not only filled to 100% capacity
by March 2009, well before the La Nina weather pattern took hold, and then
overfilled with the volume well above twice the Wivehoe Dam capacity going over
the dam wall by January 2011.
In their scramble for authenticity they added a further two
years to the "drought" being years 2008 and 2009. You will see the
evidence that in those two years the catchments had rainfall of 125% of the long
term average.
The QCCCE therefore had a two-pronged excuse for low dams of
"drought" and "Climate change". Because these excuses were
accepted, research into the underlying cause of depleted dams was blocked and,
as a consequence, contributed to considerable damage from flooding in Brisbane
and Ipswich.
It was also consequential in producing a water grid costing
billions of dollars that is largely ineffectual.
Viewed in QCCCE
Return to Index foreword
************************
Flood Proofing
start
Flood
proofing
Brisbane
from damaging floods to the point of extinction
Mitigating flooding in
Ipswich
and Gympie
***************************
Full index
Flood proofing
* Borumba dam integration. Where is it and what does it
look like. Click
to go direct
* Overflows lost to our water supply Click
to go direct
* Flows above and below the dams Click
to go direct
* Flood volumes Click
to go direct
1.
Overview
2. Reported flood volumes
3.
How has the Wivenhoe Dam performed since installation
in 1985?
4. Review of Bremer River and Lockyer Creek
5. Logic of flood mitigation in Brisbane
6. Flood mitigation in Gympie
7. 1841 and prior
8. The largest flood to contain
* How to deal with major floods Click
to go direct
1. Saturation rain
2. Flood
compartments available
3. FSL or commonly
known as “drinking water” compartments
4. Total capacity
to retain floods if all the compartments are available.
5. How does this work?
6. How do you cover your gamble if it does not pay off?
* Borumba dam integration the answer Click
to go direct
Drought proofing Click
to go direct
1. Another look at our so-called
"drought". These drought like breaks in our
water supply are more severe than any hydrological drought.
Water share between the
Ecology and residents of South East Qld. Click
to go direct
Return
to Foreword
*******************************
Borumba Dam integration with
Wivenhoe/Somerset: Where is it and what does it look like
This involves the integration
of the Borumba Dam 40 Klm over the hill from the 
Somerset
dam with the Wivenhoe/Somerset Dams. It has the dual purpose of backup supply
enabling the Wivenhoe Dam to be permanently lowered and further lowered to be almost empty before a major flood. With two-way
pumps capable of transfer rates 32 times the output of the Tugun desalination
plant, normal water supply will be available during any "drought"
period.
Click to view the location of
the dam
This is the low cost expanded
Borumba Dam to 2,000,000ML for 
storage and later return to the Wivenhoe/Somerset
system. The cost for the Dam expansion, hydro plant, pipes and pumping equipment
has been costed by engineers at no more than the Tugun Desalination plant.
Click to view the current dam and view from the
ridge
CLICK HERE
to view channel 10's review of this Dam. It
includes an interview with local grazier Ron McMah. Trevor Herse, retired of the
Gold Coast and myself were well aware of the huge water surpluses of the
Wivenhoe/Somerset catchments from "low pressure systems". We coordinated
with Ron who had identified the storage capacity for these surpluses in putting
forward this proposal.
One will notice that the topography of the
Dam with high hard rock walls makes it suitable to expand to a capacity larger
than the Wivehoe/Somerset Dams as certified by engineers.
Return flood
proofing index
Overflows lost to our
water supply
With the figures now confirmed a volume of
water equivalent to 229.5 percent of the capacity flowed over the dam wall in
January 2011. This is in addition to the 55.5 percent that had been released in
October 2010 to December 2010. That total of 285.0
percent was lost without a Megalitre being saved.
It gets worse, 25% of the Wivenhoe has now being
released. This means that during the recent events we are 25% of the Wivenhoe
capacity worse off than when it started.
The dams began filling in 2007 and have been
full since March 2010. This date is well before the La Nina
weather pattern took hold.
There was no reserve supply sufficient to
permit early release of our FSL “drinking water” compartment to avoid
damaging flooding. That water is regained at the back end of the flood.
Return flood
proofing index
Flows above
and below the dams
Those who who would have believe that 50% of
flood water comes from below the dams are badly astray. They rely on catchment
areas without the application of rainfall statistics.
According to the Water Resource (Moreton)
Plan 2007 by their official IQQM computer model, the Wivenhoe/Somerset provides 56.5% of all
water that reaches the mouth of the
Brisbane
River. 58.0% below Mt Crosby. 56.5% means that water above the dams was
30% more in volume than below the dams. In this 2011 flood, based on
evidence presented to the Flood Inquiry, it was 65% above the
dams. Again that converts to 85% more in volume than below the dams.
The temporary retention of "above dam" flood
waters clears the way for the
Bremer
River, Lockyer Creek and the
Brisbane
River
itself to run free minimising impact to just 42 percent of the entire flood. In the
case of the 2011 flood it would have been reduced to just 35% of the flood.
This set of numbers following was published by
Engineers GHD in December 2011. It was based on Seqwater Historical Flood Events
Hydrographs. The 1893a flood had only 23.82 percent of the flood below the dams
coming from the main tributaries. Similarly the 2011 flood had only 34.94 per
cent below the dam. I have placed the 1974 above dam total in red and I refer to
my official supporting information. It indicated
the 1974 above dam flood is 2,200,000ML based on official supporting documents.
This reduces the below dam percentage to 42.0 percent.
Nevertheless the GHD figures supplied by
Seqwater indicate that the 2011 flood had a volume above the dams of 138%
more than the 1974 flood. This is a major departure from Seqwater claim of 190%
in their much criticised document lodged with the Flood Inquiry.
When viewed with the the 50% catchment area
above, it does not give one confidence in the rest of the document.
Return flood
proofing index
Flood
volumes
1.
Overview
2. Reported flood volumes
3.
How has the Wivenhoe Dam performed since installation
in 1985?
4. Review of Bremer River and Lockyer Creek
5. Logic of flood mitigation in Brisbane
6. Flood mitigation in Gympie
7. 1841 and prior
8. The largest flood to contain
Overview
The essential element to flood proofing Brisbane
is to know the inflows that occurred since records were kept from 1890 to 2010.
This is to determine the flood with the largest inflow volume in the
Wivenhoe/Somerset catchments. It is that flood that we must contain.
If we are successful in retaining the
largest recorded flood then 58% of the entire flood is taken out of the equation and
released without harm at the back end of the flood. It is the peak that does the
damage. The 58% is calculated by the IQQM computer model that has the force of
Law in calculating the 66% required for the Ecology.
This permits the
remainder of 42% being the Bremer
River, Lockyer Creek and the Brisbane
River’s own contribution to run free avoiding the backwater
and barrier created by the
Wivenhoe/Somerset outflow.
Reported flood volumes
Seqwater and Brisbane City
Council reports have similar volumes and obviously are reading from the same
gauges.
The reported flood volumes
are:
2011 2,650,000ML ( revision GHD report Dec 2011 : 2,380,396ML)
1974 1,410,000ML ( revision GHD report Dec 2011 : 1,724,841ML)
1893 2,744,000ML ( revision GHD report Dec 2011 : 2,799,234ML)
If accepted, then 1893 at 2,744,000ML is the largest flood that we have to deal with and nothing further
needs to be examined. We will see that this volume is capable of being
withheld with room to spare. ( GHD report of December 2011 records it at
2,799,234ML)
My review of flood volumes can be examined
in the Flood Review tab.
The review suggests to me that a volume of
3,000,000ML will cover all contingencies.
If further examination is sought click FLOOD
VOLUMES
How has the Wivenhoe Dam performed since installation
in 1985?
The floods of note are 1999 and 2011.
The 2011 flood is under close scrutiny of
the Flood commission. The decisions made at flood time are most likely to
subject to legal challenge well into the future.
The 1999 flood was on normal and not
saturated catchments. The Wivenhoe was at 74.5% of capacity at the start and
135.1% at the end. The Somerset was 44.6% of capacity at the start and 154.2% at
the end.
Seqwater placed the flood volume at
1,220,000ML or about 51% of the revised volume for 2011 of 2,380,396ML. That
volume for 2011 included 540,000ML for a small flood not fully released early
which is the nub of legal argument.
Review of Bremer River and Lockyer Creek
The submission lodged by the Ipswich Council provided some
some insight into how floods affect that City. Three of those points are:
1. Damage begins to occur once the flood height at the railway
bridge reaches 14 metres.
2. The flood waters of the Lockyer and Wivenhoe/Somerset create a barrier for
the Bremer River.
3. Backwater occurs in creeks at or below the Bremer River mouth.
There were 4 floods in recorded history that passed the 14
metre mark. They were 1893 Feb 24.5m; 1974 Jan 20.7m; 2011 Jan 19.25m and 1931
Feb 15.47m.
GHD figures are enlightening when reassembled to see the
pressure that the Lockyer Creek and Wivenhoe/Somerset catchment place on the
Bremer River.
Lockyer Creek produced more volume of water than the Bremer
River in all floods.
An example of the pressure of backwater is in 1974 the Bremer
flow was 631,195ML whereas the 1893 flood had a flow of 196,825ML which is less
than 1/3 of the 1974 flow. Yet the Bremer River Height was 24.50m in 1893
compared to 20.70m in 1974.
Above left are the Seqwater flows 1893, 1974,
2011 Right picture is 1931 rainfall
The hydrological analysis of Ipswich in the 2011 flood had the
one mile bridge at 6 metres above due to backwater.
On that basis, the 1893 and 2011 floods would have been kept
below the damaging 14 metre mark.
However, the 1974 flood at 20.70m had to reduce by 6.70m to
avoid damage. The rainfall and resulting flows were much higher than ever
experienced. My Ipswich correspondents, having experienced the flood, say that
may not be the case. Hydrological and hydraulics reports will be necessary.
Review of the 1931 rainfall is enclosed. Withholding of the
Wivenhoe/Somerset will reduce it from 19.25m to below the 14.00m mark.
Logic of flood mitigation in Brisbane
* The highest flood volumes from the Wivenhoe/Somerset is 1893
which this website explains can be contained until after the flood.
* There is a caveat on the 1974 flows for the
Wivenhoe/Somerset as the pre-development flows of DERM and the rainfall stations
information both conflict with Seqwater volumes. The indications are that the
percentage above the dams is in line with the DERM information of 58% average
above Mt Crosby over 110 years.
* With the Wivenhoe/Somerset held, the waters of the Lockyer
and Bremer run free.
* We know that the 1893, 1913, 1974 and 2011 floods should be
below the damaging 14 metre mark in Ipswich with a caveat on 1974.
* A similar pattern should show up in Brisbane.
Flood mitigation in Gympie
The Borumba Dam stands on Yabba Creek. It is researched
throughout this website as it was the subject of our submission to replace the
proposed Traveston dam.
My calculations for the 1999 flood is that Yabba Creek
provided 34.8% of the total flow through Gympie. To review click on Hydrology
Mary Valley
As we will see later on this page, the major part of this
proposal is the expansion of that dam from the current 45,000ML to 2,000,000ML.
It will provide ample opportunity to mitigate flooding in Gympie to the extent
of 34.8% of the flood.
Yabba Creek in full flood 2011(Gympie times photo)
1841 and prior
The
Queensland Parliament at the time of the 1893 floods recorded that the 1841
flood was 7 inches (.2 of a metre) above the 1893(1) flood. The archaeological
find at Indooroopilly, being up river, may well come in under the 1893(1) flood
because up river heights are much higher.
******
For those who appreciate an easier read than the language of
this accountant, click on Trevor
Herse for his "Water woes result from misunderstanding and blunders". Trevor and I,
together with Ron McMah, grazier, of Imbil, have worked together on this project since 2006. We
represent no one and have in mind only the interests of citizens of South East
Qld.
*********
The containment of a flood to 3,000,000ML is the target.
Return
flood proofing index
How to deal with major floods
1. Saturation rain
2. Flood
compartments available
3. FSL or commonly
known as “drinking water” compartments
4. Total capacity
to retain floods if all the compartments are available.
5. How does this work?
6. How do you cover your gamble if it does not pay off?
Saturation rain
Saturation rain
preceded all of the floods under review. It is certain that the FSL “drinking
water” compartments were, or would have been, full.
Flood
compartments available
The official flood
compartment volumes are Wivenhoe 1,450,000ML and 
Somerset 524,000ML for a total
of 1,974,000. This represents 170 % as a percentage of the Wivenhoe capacity for
easy measurement. Mr Ian Chalmers, the chief supervising engineer in the
construction of the Wivenhoe has suggested in his submission the relocation of
the fuse plugs to maintain these volumes.
FSL or commonly
known as “drinking water” compartments
These compartments
are not normally reduced as the metrological events that fill them come on
average every 3.7 years. Their fill usually represents 95% of the water in the dams.
Click to
view official dam statistics Wivenhoe/Somerset
These compartments
measure Wivenhoe 1,165,000ML and Somerset 380,000ML. The total is 1,545,000ML.
This total represents 132 per cent of the Wivenhoe capacity.
Total capacity
to retain floods if all the compartments are available.
The flood
compartments total 1,974,000ML or 170 %. The FSL or “drinking water”
compartments total 1,545,000ML or 132%. The combination is 3,519,000ML or 302%.
The largest flood
of 3,000,000ML represents 258% of the Wivenhoe Dam FSL. This can be held by the
flood compartments of 1,974,000 plus the FSL of the wivenhoe at 1,165,000ML
which totals 3,139,000ML or 270% of the Wivenhoe capacity. The Somerset FSL is
not needed.
How does this work?
There is always
the quandary “will flooding rains come or will they not?”
Our weather
forecaster are becoming more reliable in predicting 
major
events in our weather patterns. This article written by Brian Williams of the
Courier appeared in their paper on the 1st October 2010. He points out that all
dams are full and the weather patterns that produce flooding rains were
entrenched. I have observed that throughout the flood period Brian Williams was
accurate in reporting all events of the flood and that his reports could be
relied upon.
It is necessary to
early release the FSL “drinking water” compartments with the recent Bligh/Robertson
decision in progress (28/02/11). As events unfold and the flood is reasonably
certain, further releases from these compartments should be made at the front of
the flood thus allowing the Bremer River, Lockyer Creek and the Brisbane River
to run free.
This avoids the
backwater and congestion of the Wivenhoe/Somerset releases. The extent of the early
release will depend on the Meteorologists and their telemetry equipment.
It is a considered
gamble on weather predictions.
If the rains do
not come then you lose heavily as you have released your precious drinking water
with almost no chance of recovery until the next “uncommon event”.
If the flooding
rains come, you win well. Not only have you assisted in reducing damaging flood
levels by taking the water from the Wivenhoe/Somerset out of play but most, if not all of the water
released, can be recovered at the back of the flood.
How do you cover your gamble if it does not pay off?
This is an example of a
feeble attempt but a step in the right direction
Minister Robertson supported by Premier
Bligh made the decision to release 25% of the capacity of the Wivenhoe dam’s
“drinking water”. The backup explained by the Premier was the Wyaralong Dam
which represents 6% of the Wivenhoe capacity.
The additional backup is the Tugun
desalination plant and the recycled water that a lot of people dislike. The
Tugun plant takes 34 years to fill the Wivenhoe/Somerset dams from scratch if we
do not take water out. The recycled water takes a bit longer.
The consequence is that we will be out of
water in 3 to 4 years 
if an “uncommon event” does not appear in the normal
average of 3.7 years. It is a very high price to pay for such a small gamble on
the weather. The Wivenhoe dam level chart with red lines shows that we rely
almost entirely on "uncommon events" to refill our dams.
Click to view "uncommon
events" in the Wivenhoe dam 1988-2007
When one exceeded the average in 2001-2007
it was misrepresented as a "drought".
Return flood
proofing index
Borumba
Dam -The
obvious major reserve supply
The reserve supply needs to be in place
permanently. The decision making process on release will depend on the
concentration of the rain and will determine how much is
released without the flood event happening.
It is most likely that no more than 60% of
the Wivenhoe capacity would be released without the flood event occurring. This
volume is 700,000ML. It is stored for later return if needed by the
Wivenhoe/Somerset system.
A proposal to maintain a significant
percentage permanently in the Borumba Dam and have a corresponding permanent
reduction of the FSL- "our drinking water" has merit. It will give the
dam operators more flexibility to early release.
This is well within the storage capacity of
the Borumba Dam expanded to 2,000,000ML. This capacity is larger than the
Wivenhoe/Somerset dams total capacity.
Borumba Dam - a brief resume
The dam already exists
It is a hard rock natural amphitheatre ideal
for minimal evaporation.
Has its own small but efficient catchment.
We own all the land and no disruption to people of the Mary
Valley
.
It is 60klm over the hill in the Mary Valley.
The
Queensland
Water Commission has expansion to 350,000ML in the SEQ Water Strategy
Engineers say it can be expanded to 2,000,000ML or larger than the
Wivenhoe/Somerset dams.
1,500,000 for storage and 500,000ML for the Mary
Valley
Partial flooding of Gympie avoided. Yabba Creek on which it stands provides 34%
of flood water to the Mary River.
Regeneration
of the Mary Valley from its damaged state which resulted from the scrapping of
the Traveston Dam proposal.
The costing by engineers of the dam wall is $1.4 billion including the Hydro plant. Engineering view is that the pipes and
pumping equipment are in the region of $0.5 billion. Deduct the QWC proposed dam
of 350,000ML and we arrive at a cost about the same as the Tugun Desalination
plant.
This compares with the Insurance Council of Australia assessment in 2007 that a
1974 type flood "represents a potential insurance loss of $1.8 billion and a
simply staggering loss for both Government and the affected community"
Borumba Dam proposal and appendix on
cancellation of Traveston Dam
The Traveston is now historical but the alert to Minister
Hinchcliffe and the use of the Borumba Dam as its replacement is still valid.
These two proposal and appendix were submitted to the Queensland Water
Commission when they were called for after the cancellation of the Traveston
Dam. This
procedure eliminates the planned three desalination plants and avoids most of the
construction and ongoing costs. Further reading Borumba
Dam Proposal and Borumba Dam Appendix
Return flood
proofing index
Drought
proofing start
Drought
proofing SEQ.
1. Drought in the catchments. Conclusive proof
that it did not exist.
2. Different approach to "drought
proofing".
1. Drought in the catchments. Conclusive proof that there was no
hydrological drought in the
catchments
Former Premier Beattie, Premier Bligh and now Minister
Robertson claim that South East Queensland is "drought proofed".
This section provides a different view suggesting that this
phrase is misused to justify an expense in the region of $9 billion according to
Mr Kim Wood CEO of Allconnex water (Refer WATER COST). An
expensive cost brought about by those who should have displayed more diligence in
the control of our water supplies.
This phrase "drought proofing" belongs with the "worst drought in 100
years" when related to the low levels of water in our dams. The evidence
presented in this section is
that while there was drought in most parts of the State, there was no drought in the
catchments.
I have overlaid the Wivenhoe dam level graph with
"uncommon events" as described by Mr Drury of SEQWater in the header
above. The dam decline from each refill is marked in red.
That decline was obvious soon after the Wolffdene dam was 
cancelled
for political reason in 1989. By 1992 it was obvious that normal "summer
rain" was inadequate for our needs and we relied heavily on these
"uncommon events". A longer period beyond their 3.7 year average
would, and did, bring us grief with no provision by those in charge.
Click to view "uncommon events" in the
Wivenhoe Dam 1988-2007
A convenient statistical aberration of a "decile"
map was used to avoid scrutiny. The "decile" map was showing
"lowest on record" for the rainfall, while the corresponding "percentage" map
read 80% of the long term average. This can be viewed at DECISION
MAKERS
The Bureau of Meteorology rainfall stations in the catchments
were at the same time showing 99.1% for the Wivenhoe and 91.4% for the Somerset
for summer rainfall December to March. Viewed at the bottom of the RAINFALL DEFICIENCY
page.
A further example of timing of "uncommon events" is
this comparison. With a time period of 3 years and 9 months, the February 1992
to 
November
1995 was right on average of 3.7 years. The dam level dropped from
100% to 44.3%. Bureau of Meteorology maps show that there was no drought in that
period with rainfall 90% to 100% of the long term average.
Click to view comparison
Comparing the same 3 years and 9 months period of the
"drought" February 2001 to November 2004, the level dropped from 100%
to 53.4%. We held
9.1% more in reserve than in a
period with
no drought.
It is now certain that there was no drought in the catchments 
for the 2001 to 2007 period. It was simply the operation of low pressure
systems. The 2001/07 period was an object lesson in how the 3.7 average works.
Most are below that average so the few that are above can be quite
lengthy.
More recently there have been attempts to extend the
"drought" to years 2008 and 2009. I have forwarded to the Qld Flood
Inquiry the Bureau of Meteorology Rainfall graphs for those years which show the
rainfall in the catchments 125% of the long term average.
Premier Bligh
and Minister Hinchcliffe were warned of this mathematical certainty that Low
Pressure Systems would return and overfill our dams.. Click to move to these
warnings.
The importance of this is that forward planning by the
Queensland Water Commission in its strategy for SEQ is related to preparing for a
"drought".
Our main water supply is low pressure systems. They are random and can occur at
any time of the year and for much longer than any "drought". They
are oblivious to the conditions prevailing at the time.
2. It requires a different approach to drought proofing.
It requires a different approach from the present stance of
"drought proofing" SEQ.
The current claim of "drought proofing SEQ" is in
the same category as "worst drought in 100 years". They both do not
stand up to scrutiny by a long way.
The current "drought proofing" relies on the
Desalination plant at Tugun which can produce 45,000ML a year. The recycled
water produces almost the same based on Premier Bligh's most recent comments.
Seqwater spokesman advised that the current release of 25% was
one year's "drinking water". That is 291,000ML a year. The official "allocations" made from the Wivenhoe/Somerset dams are 286,000ML so
the spokesman is near the mark. Deduct the
90,000ML from Desalination and recycled water and we have a shortfall of
200,000ML each year for the length of the "drought".
On
the other hand the two-way pumps between the Wivenhoe and Borumba Dams can have transfer rates of up to 4,000ML per day compared to using the expanded Borumba Dam
storage of the Wivenhoe/Somerset water for later return
The
objective is to maintain the wivenhoe/Somerset dams above 40% level before recycled
water is introduced. This is on 
the basis of a yield of 373,000ML which is
considerably higher than the 286,000ML presently allocated.
Click to view the simulated levels in the Wivenhoe
Dam for the last 100 years
On the past history of 120 years, it would
require no more than 500,000ML to be retrieved from the Borumba Dam for a period of three to four years at the
bottom of the drought cycle. It would have happened only twice in those 120 years.
Pumping
to the expanded Borumba Dam would be undertaken when dam levels are high
creating space in the Wivenhoe/Somerset dams to capture as much as half of the
55.5 per cent overflow created in October/December 2010.
Engineers
have costed the dam wall to $1,397 million. It includes a hydro plant. Add to
that an engineers estimate for the pipes and pumps of $500 million and deduct
the unknown cost of the Water Commission dam wall to 350,000ML and we have a
cost equivalent of one desalination plant of the Tugun size.
Compared
to the high cost desalination, the operating costs are minimal. The spare
capacity can be filled over a number of years with little draw down required.
The Hydro Plant will be operating full time as water is already used by the
Gympie and district people.
The
proposed three desalination plants will not be required.
The
WATER SHARE Tab is recommended reading to this
proposal. It is examined on the "WATER SHARE" Page in this website.
In
essence the well credential Technical Advisory Panel who examined this
allocation recommend that 66% of all water that passes through the
Wivenhoe/Somerset dams must reach the Brisbane River mouth. It is now the law
(March 2007). I
have no problem with that percentage.
However
in the writing of the Act the Technical Advisory Panel's advice, that large
floods should not be included when calculating the permanent base on which the
66% is calculated, was ignored.
The
base on which it was calculated included the four major floods of 1890, 1893
(two) and 1974. The result is that when applied against the 113 years 1894 to
2006 (excluding 1974) the percentage rises to 78%.
It cannot be disputed, it is straight forward simple arithmetic. Readers will have no difficulty understanding this when they view the official
chart of inflows into the dams for 1890 to 2000 on the "water share" page.
The
effective result is that a volume of water equivalent to the proposed, and now
cancelled, Traveston dam is redirected from our consumption to the ecology every
year. That is 160,000 ML.
In
today's terms the massive infrastructure of the Wivenhoe/Somerset Dams, which
cost $550 million, would equate to a cost more than $1 billion. It has been reduced from
SEQWater's public records of 446,950ML annual yield to allocations of just
286,000ML by the introduction of this Law in March 2007. The fundamental
arithmetic flaws need to be corrected. (A yield is the volume that a dam can
produce in a year without running dry. It is calculated in this case over 111
years).
While
this fundamental arithmetic flaw exists, the Water Strategy for South East
Queensland is severely affected and will involve major costs on the drawing
board that are not necessary.
Back
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*******************************************
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