Webmaster’s observations:

The CEO’s “answer” to question 4 is akin to that of a vendor who, when asked “What’s the price of that?”, replies “There’s an 18% discount on it” – the thing being unpriced… This shifty style of “answer” is getting annoying.

The Mayor’s refusal to answer question 5 is, I’m sorry to say Jayne, childish, and not fit for a Mayor. Public responsibilities mean allowing for and planning for catastrophes, which do happen even though this is unpleasant to consider… Cr Liu, as an engineer, reminds Council of this basic reality, and his question is legitimate, whatever your semantic grasps of the conjunction “when”. To play exagerated offense is to play ducking – a smallish political game.

One more comment is warranted in this endless saga of the Penneshaw sewerage plans, which is costing some money to the ratepayers. In September 2011 and May 2012, a compromise solution was put forward by councillors Walkom and Liu, to proceed with the CWMS in this town only in the foreshore zone where this was really needed, with the hotels and tourist transport infrastructure (Sealink). This reasonable and no-nonsense motion was twice declared ultra vires (i.e. invalid) by the Mayor and thus not voted. Pity.

Considering the real risks of pollution and destruction associated with the planned sewage dam, council should consider to stop being stubborn, listen to the opposition in Penneshaw (spearheaded by brave Mrs Knight), rather than being full of contempt for it… and get back to less grandiose and more feasible sewerage plans.

UPDATE:

Penneshaw : the LGA CWMS committee (2013.03.25) is not prepared to subsidise the full scheme

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Questions on Notice by Kangaroo Island councillor Ken Liu

Penneshaw CWMS Storage Lagoon

April Council Meeting 10/4/2013

Question 1:

Given concerns of a dam break risk was raised at the May 2012 workshop, did the CEO seek additional information from Council’s consultant on:-

a)      Inundation mapping of affected areas below the lagoon;

b)      Population at risk (PAR) assessment;

c)       Cost of property damage; and

d)      Social, health and environmental analyses,

in the event of a disaster, to enable Elected Members to understand the public safety, potential liability, due diligence and duty of care issues associated with the dam, before making the decision at the June 2012 meeting to approve the preferred site for the lagoon which is a short distance from houses ?  If so, please advise the additional information tabled at the meeting?

Answer 1:

The Consultant was present when the issues associated with the lagoon site were discussed – break was not, from memory, specifically raised or noted at this time, although it would appear that the Councillor believes that it was. The designs were preliminary for the purpose of determining likely capital and whole of life costs and subject to the availability of funding from the subsidy scheme the designs would then be formalised and it is expected that all required assessments would need to be completed prior to formal acceptance of design and subsequent Development Application. As the Councillor would be aware, no additional documents were submitted to the June Meeting – the decision to approve the preferred design for submission to the LGA CWMS Management Committee for likely subsidy calculation was just for this purpose.

Question 2:

If the answer to (1) above is ‘No’, was the CEO satisfied with the amount of material provided to the Elected Members at the May 2012 workshop that was considered adequate for them to make an informed and responsible decision on the location of the treatment plant and storage lagoon in the interests of the community as required under Section 6(a) of the Local Government Act 1999?

Answer 2:

It was made quite clear to Councillors that the workshop was about understanding the options and likely costs of the options presented and from this deriving a preferred design for formal cost analysis by the LGA CWMS Management Committee for the purpose of confirming that subsidy would be available and the likely total of the subsidy available.

Once these figures have been calculated and confirmed as acceptable, our Consulting Engineers would then need to finalise the designs and the reports that accompany them to the point where the available material is ready for Council to approve the formal Development Application process commence. To this end the amount of printed material available, together with the discussion held on the day seemed to be sufficient for the Elected Members present at the June 2012 Meeting to form their opinion and then confirm by formal decision at this meeting that the preferred designs be sent to the Committee for final costing and subsidy calculation – all that was asked of them in the recommendation at the time.

Question 3:

Other than the Development Act 1993, are there any legislations or statutory requirements in the State of South Australia and recognised National guidelines and codes for the design, construction and management of large earth embankment dams within an earthquake zone, which Council must comply with in order to obtain a permit for the storage lagoon as proposed for the Penneshaw CWMS?

Answer 3:

The dam design will need to consider the application of the “Guidelines for Design of Dams for Earth Quake” published by ANCOLD. These guidelines were developed for large dams as defined in the glossary from the guidelines.

Definition of Large Dam

A large dam is defined as one which is:

(a)    More than 15 metres in height measured from the lowest point of the general foundations to the ‘crest’ of the dam,

(b)   More than metres in height measured as in (a) provided they comply with at least one of the following conditions:

(i)                  the crest is not less than 500 metres in length

(ii)                the capacity of the reservoir formed by the dam is not less than I million cubic metres

(iii)               the maximum flood discharge dealt with by the dam is not less than 2000 cubic metres per second

(iv)              the dam is of unusual design

No dam less than 10 metres in height is included.

A risk based approach would need to be adopted in the detailed design.

In addition the geotechnical site conditions will need to be assessed in order to determine a suitable embankment design for the structure. When referencing the guidelines it needs to be noted that the storage lagoon currently being considered for Penneshaw has an approximate capacity of 20 ML. The internal wall is less than 6m high from floor to crest. The external batter of the wall is up to 20m in elevation to the crest as it follows the natural contour down slope.

Question 4:

In light of your advice (March 2013 QoN), what was the estimated construction cost of the treatment plant and storage lagoon (detailed within sheets C08 &C11 supplied at the May workshop) submitted to the LGA for subsidy funding and was an extra cost factored into the estimate for the dam being located within an earthquake prone zone?  If so, what was the amount allowed in the calculation?

Answer 4:

The cost for the construction of the treatment plant and storage lagoon took into account all requirements for their proper design, approval and subsequent construction costs. An element of 5% contingency was added to the lagoon costs specifically to deal with challenges associated with construction and this was in addition to the general 8% allowed for general project contingencies and 10% contingencies allowed for in the costings for the reticulation system.

Question 5:

Which properties below the storage lagoon are on the flood path when the dam is full, overflowing through the spillway rushing down the hill onto the residential area between Cheopis Street and Lashmar Street?  To what extent is damage expected to occur along the flood path and will lives be at risk when this situation occurs?

Answer 5 (by the Mayor)

“I have ruled that question 5 will not be answered as it is improper and misleading ….To explain my ruling, your question implies that the Council would build something that will fail and put lives at risk. I have underlined the word, ‘when’ within your question, that gives the impression that it is certainty that this dam will fail and lives will be lost.”

Note: Local Government Meeting Regulation 10(6) – The presiding member may rule that a question with or without notice not be answered if the presiding member considers that the question is vague, irrelevant, insulting or improper.

Reply to the ruling by Cr Liu:

Question #5 is about which properties will be on the flood path and what possible damage could result to these properties when water flows through the spillway from the dam.  At no time was a suggestion made that the dam will fail. A ‘spillway’ is an integral part of a dam designed for the release of water in the lagoon when it reaches its maximum storage capacity, to prevent water overtopping the earth embankment.  Excess water discharging over the spillway at a high velocity will occur which is an inevitable event and there is no reason why this information could not be made public, in the best interest of the community who may be exposed to this risk. 

Mayor’s ruling remained and the answer [to question 5] was not provided.

Cr Ken Liu

Kangaroo Island Council
P O Box 80, KINGSCOTE  SA  5223
Ph: (08) 8553 2823   Mobile: 0428 322 005
Email: ken.liu@bigpond.com