Author : J. V. Hodgkinson F. C. A. Chartered
Accountant : Aug 2006 to April 2013
The principal thrust of this
This is my review based on official
statistics and documents. It is done in conjunction with Ron McMah, grazier
of Imbil and Trevor Herse, retired of the Gold Coast
The following is examination of material that was interesting at that time. It is kept in the website for information.
A Click will give you an alternative view of why our dams depleted in the first place. If it is not understood, then the solutions offered have no real base. It looked like a "drought". All around Queensland was in drought, and the waters in the dams were at their lowest level since the commissioning of the Wivenhoe in 1986. So what was it that caused the depletion?
It was the random nature of large events outlined by Mr Drury of SEQWater at the introduction above. 300mm in a few days is a flood capable of filling the dams from scratch to overflow but on the other hand the same rain distributed over 3 months of 100mm per month is a comparative trickle. They pay no attention to the time of the year and occur on average every 3.7 years.
As we are seeing at present, the dams are too small to control the water supply for the ecology and ourselves. The Borumba dam, just over the hill in the Mary Valley, is currently quite small but can be expanded to almost twice the size of the Wivenhoe.
Whose water is it?
In March 2007, the State Government legislated that 66% of all water that passes through the Wivenhoe/Somerset dams must reach the Brisbane River mouth. That means that only 1/3 of the water in the Wivenhoe/Somerset dams is for us and 2/3 for the ecology. Click on water share for additional information. It will give one a better understanding as to why there is no lifting of water restrictions.
This website, developed since 2007, has reached a point where, with dams full, it may be useful to reflect on events so that the acknowledged errors of the past may be avoided in the future. Failure to do this in the period 1989 to 2001 following the cancellation of the Wolfdene Dam, produced a catastrophic period 2001 to 2007. It was incorrectly blamed on a multitude of things but the main underlying excuse was the non-existent "drought" in the catchments, proof of which will follow.
This examination covers a wide range of topics that includes
such matters as:-
* "Drought" of 2001 to 2007
"Drought of 2001 to 2007"
The Bureau of Meteorology
tab offers the following:
The Decision Makers Tab
offers the following:-
The Federation Drought Tab offers the
following. It is supported by Rainfall 2001-06:-
What was common to both periods was the absence of "Uncommon events" being highly concentrated rainfall as outlined above. They both exceeded the 3.7 year average of these events.
The QCCCE is an organisation that is difficult to deal with. No one person appears in charge and my enquires seem to end up in the Department of Environment and Resource Management or its fore-runner Departments with different names. That Department is also responsible for the IQQM computer model which must, by law, calculate the hydrological pre-development flows.
The Depleted Dams Tab
Assists in drawing together the above and adds additional
* Population growth. There is no
sudden uplift that caused the dam levels to drop. Population was predictable and
Climate change can be examined by combining rainfall in 30 year lots similar to the method used by the Bureau of Meteorology in comparing rainfall. Both catchments are shown. The situation appears constant.
Uncommon Events are our main water supply
The Uncommon Events
Tab offers the following observations.
Consequences of the miss-interpretation of the action of these events
Additionally the Uncommon Events Tab offers two main photos that point to miss-interpretation of their actions.
*The second last photo, being the Wivenhoe Dam levels,
shows that the cancellation of the Wolfdene Dam was decided at a time when the
dams were full by the April 1988 and April 1989 Uncommon Events. This is an
admitted error that ultimately cost billions of dollars and disrupted peoples
This was the root cause of the depleted dams in the 2001 to
2007 period. A gap of six years was experienced. A convenient statistical
aberration was use to justify the term "drought" thus hiding from
Traveston Dam and alternative proposal
* This three stage dam was the main thrust of the answer to
"drought-proofing" South East Queensland.
* Mr Ron McMah, grazier of Imbil, put an alternative to the then Deputy Premier Anna Bligh to raise the Borumba Dam from the present 46,000ML capacity to 2,000,000ML and add a pipeline from it to the Wivenhoe/Somerset for storage as the capacity of the Wivenhoe/Somerset was inadequate to hold the flood waters of that system. She agreed at a public meeting at Gympie, that was the way they would proceed if it "stacks up".
* The proposal and the appendix to it has been lodged with the Queensland Water Commission who called for submissions of the draft South East Queensland Water Strategy. While the Traveston has been scrapped it still has relevance in elimination most, if not all, of the proposed desalination plants
You cannot take water out of the Wivenhoe/Somerset system! (True or false)
The approach of the Queensland Water Commission to the McMah proposal made it doomed to failure in a very short time. The Hydrologists and Engineers were both advised that there was no water available from the Wivenhoe/Somerset system. They prepared their report on that basis excluding the necessary Wivenhoe/Somerset and pipeline. The Engineers did provide a costing for a similar size dam wall approximating a dam of 2,000,000ML which was useful.
* There are two possible reasons for that advice being :-
We will cover both as they are both relevant.
1. Yield of the Wivenhoe/Somerset.
* This was determined by SEQWater, the dam managers in 2001
and 2002 annual reports at 446,900ML Currently the "allocations" are
286,000ML for our use in SEQ. This leaves 160,900ML available and no requirement
for desalination plants.
* The McMah proposal explains that in only two short periods in the last 120
years did this condition occur and is quite easily handled in the Borumba
Appendix. This then releases 83,000ML and contravenes the statement
"You cannot take water out of the Wivenhoe/Somerset system".
2. Complications introduced by the Water Resource (Moreton) Plan 2007 enacted in March 2007.
* Minister Stephen Robertson made it clear to me in his
letter of the 6th August 2009 that the
principal constraint of the proposal was that 66% of all water in the Brisbane
River system had to reach the Mouth of that River.
While the 66% is accepted, the use of the calculation period of the 111 years 1890 to 2000 appears to dissent with their own literature. It includes the floods of 1890 and 1893 which when compared to a base of 113 years 1894 to 2006, we find that the use of that now permanent percentage based on 1890 to 2000 converts to 75% for the ecology and denies us 130,568ML annually or the equivalent of 3 desalination plants of the Tugun size.
This is more fully discussed on Water Share including graph of the pre-development inflows which clearly shows the distortion created by these two floods.
Correspondence with two of the most senior professors is ongoing. (June 2010)