Rodriguez & Sons Pty Ltd v Queensland Bulk Water Supply Authority trading as Seqwater

Revision 13 of the Manual

1. The relevant version of the "Manual of Operational Procedures for Flood Mitigation at Wivenhoe Dam and Somerset Dam" approved under subsection 371(2) of the Water Supply (Safety and Reliability) Act 2008 (Qld) ("the Act") governing the conduct of the flood engineers on duty in early January 2011 was "Revision 7". The approval of Revision 7 was gazetted on 22 January 2010. Seqwater seeks to tender Revision 13 of the Manual which appears to have been published in November 2015 and presumably approved at or around that time. [1]
2. One issue of critical importance to the plaintiff's case is whether the flood engineers on duty during early January 2011 were obliged to use rainfall forecasts as a basis for making releases of water from Wivenhoe and Somerset Dams in anticipation of forecast rain falling in the Wivenhoe catchment. Rodriguez contends that they were and calls in aid parts of Revision 7 of the Manual which refer to "forecast rainfall", "rainfall forecast" and "forecasts" including section 8.4 which provided, inter alia, "Flood Operations Strategies … The strategy [for Wivenhoe Dam] chosen at any point in time will depend on the actual levels in the dams and the following predictions, which are to be made using the best forecast rainfall and stream flow information available at the time: � Maximum storage levels in Wivenhoe and Somerset Dams. � Peak flow rate at the Lowood Gauge (excluding Wivenhoe Dam releases). � Peak flow rate at the Moggill Gauge (excluding Wivenhoe Dam releases). Strategies are likely to change during a flood event as forecasts change and rain is received in the catchments. It is not possible to predict the range of strategies that will be used during the course of a flood event at the commencement of the event. Strategies are changed in response to changing rainfall forecasts and stream flow conditions to maximise the flood mitigation benefits of the dams." The interpretation of this and other parts of Revision 7 which refer to "forecasts" and the like (as well as many other matters) is disputed.
3. Revision 13 of the Manual is a complete redraft of Revision 7. Section 4.5 of Revision 13 contains a number of declaratory statements about the high levels of uncertainty associated with rainfall forecasts and the risks of relying upon them to make operational decisions during flood events. Thus, for example, Revision 13 states as follows: "… because rainfall on the ground can take up to 24 hours to flow into the Dams and releases from Wivenhoe Dam can take up to 24 hours to reach Brisbane, relying on forecast rainfall when developing release plans can have serious adverse consequences due to the high uncertainties it contains in terms of depth, spatial and temporal accuracy. … Given the very large uncertainty inherent in the rainfall forecasts, the potential adverse consequences associated with implementing a Release Plan that significantly relies on forecast rainfall generally outweighs the potential benefit. Therefore, zero or minimal weight is usually given to the flow and Lake Levels predictions which have been derived from the [Flood Forecasting System] based on rainfall forecasts when selecting a strategy and developing a Release Plan (other than in the exceptional circumstance referred to below). … In summary, owing to the large uncertainty in the spatial and temporal pattern and the depth of the forecast rainfall, it is not currently possible to define objective criteria for the use of forecast rainfall in the strategies and procedures of this Manual. Accordingly, the degree of weight to be given to the predictions which have been derived from the [Flood Forecasting System] based on forecast rainfall is always a matter for the professional engineering judgement of the Duty Engineer." [2]
4. Seqwater identified three interrelated bases for the tender of Revision 13.
5. The reasoning behind the first basis commenced with a contention that Revision 13 and specifically the statements made within it about forecasts (as well as certain passages dealing with the closing of the crest gates at Somerset Dam) [3] constitute a representation about the flood mitigation practices for Wivenhoe and Somerset Dams in effect from November 2015 onwards. [4] This contention can be accepted. Next, Seqwater contended that that representation is relevant to establishing the proper procedures for the flood mitigation as at January 2011 or at least the practice that was adopted. Seqwater seeks to rely upon Rodriguez & Sons Pty Ltd v Queensland Bulk Water Supply Authority t/as Seqwater (No 11) [2018] NSWSC 368 at [20] ("Rodriguez (No 11)") where I allowed an expert in hydrology and the management and design of dams to give evidence that during flood events in Mexico and the Loire Valley in 2015 and 2016, flood mitigation by reference to rain forecasts occurred as being probative of the relevant practices as at 2011. In Rodriguez (No 11), I stated (at [20]: "Although it is not free from doubt I think there is some utility in hearing about flood operations practices in those years in circumstances where there is some reason to believe that there has not been a dramatic change in the approach to forecasts since 2011."
6. Seqwater's reliance on part of Rodriguez (No 11) is misplaced. Unlike the position with the flood mitigation practices at the dams considered in Rodriguez (No 11) there is "some reason to believe that there has … been a [potentially] dramatic change in the approach to forecasts since 2011" at least at a policy level as is apparent from the dramatic differences in the drafting of Revision 7 compared to Revision 13. Between the publication of those two versions was the January 2011 flood, the subsequent inquiry, numerous reports, this litigation and five other versions of the Manual.
7. Otherwise to the extent that the representation noted in [9] concerns the flood mitigation practices employed by Seqwater whether as at 2015 or 2011, then the evidence of that representation does not relate to a fact in issue in that it is common ground that in early 2011 the flood engineers did not make pre‑releases based on forecast for flood mitigation purposes. Indeed, that contention is the entire premise of the plaintiff's case which asserts that their failure to do so was negligent. In support of the latter contention, the plaintiff places reliance on the express words of Revision 7. Accordingly, the first basis relied on by Seqwater for the tender of Revision 13 does not justify its reception into evidence.
8. Second, Seqwater contends that Revision 13 is admissible evidence that could rationally affect the assessment of the probability of the following facts said to be in issue in the proceedings, namely: [5] "(a) That as at January 2011, it remained the general procedure or policy of Seqwater not to make pre-releases based on forecasts of flood mitigation. (b) For that to be changed, there would need to be a study by an appropriate expert and a decision at management level to adopt a new practice, as well as changes to the Manual. (c) That as at January 2011, there had been no study by an appropriate expert and no decision at management level to adopt a new practice. (d) That as at January 2011, it was reasonable for a competent flood operations engineer to regard the decision of whether to make releases to lower the dams below their full supply levels as a matter to be determined by the Minister, and not a matter to be decided upon during real-time flood operations. (e) That as at January 2011, rainfall forecasts were uncertain, and recent advice from the Bureau of Meteorology did not report a change in forecasts sufficient to suggest that a reconsideration of existing practice was justified." (emphasis added)
9. In relation to subpar (a), I do not accept that the reception into evidence of Revision 13 could rationally affect the existence of the probabilities of the existence of a "policy" of Seqwater as at January 2011 not to make pre-releases based on forecasts for flood mitigation. This follows from the apparently dramatic revision of the Manual between Revision 7 and Revision 13. Otherwise, as stated, it is common ground that as at January 2011 it was not the practice (or "general procedure") of the flood engineers to make pre-releases based on forecasts for flood mitigation purposes.
10. In relation to subparagraph (b), I do not accept that Revision 13 is evidence that rationally affects an assessment as to whether, as at January 2011, there "needed" to be a study by an appropriate expert to adopt a new practice as well as to make changes to the Manual. Even when Revision 13 is considered with all the other reports, the material rises no higher than evidence that various studies were undertaken after the flood event which led to revisions in the Manual. It is not evidence that could rationally affect the probability that as at January 2011 there was any need for such steps to be taken in order to adopt some practice in relation to the use of forecasts.
11. In relation to subparagraph (c), I do not accept that the tender of Revision 13 with any of the other reports to which reference is made below, could rationally affect a determination as to whether as at January 2011 there had been no study by "an appropriate expert and no decision at management level to adopt a new practice" in relation to rain forecasts.
12. In relation to subparagraph (d), Seqwater pointed to various passages in Revision 13 which refer to the possibility of temporarily reducing the full supply level by regulatory action taken by the relevant Minister and various statements about the balancing of the trade-offs between considerations of flood mitigation, water supply security, structural safety of the dam etc. Regardless of whether those representations are simply relied on for the fact that they were made or for the truth of what is asserted, none of them bear upon the probability of any determination of whether as at January 2011 a reasonably competent flood operations engineer could "reasonably" regard the decision of whether to make releases to lower the dams below their full supply levels as matters to be determined by Minister and not matters to be decided upon during real time flood operations.
13. In supporting the tender of Revision 13 in relation to matter (e) Seqwater also relies upon the extracts from section 4.5 set out in [7] as well as the following extract from Revision 13 which purports to recite the effect of correspondence received from the Bureau of Meteorology ("BoM"): "These quantitative forecasts have a high degree of uncertainty. The BoM has advised that the quantitative rainfall forecasts they issue are too unreliable to be used as a basis for predicting definitive future Lake Levels and river flows and making releases from the Dams. "While there is often the ability to forecast the potential for a significant rain event to occur in the southeast Qld-northern NSW region, it is difficult (if not impossible) to predict the actual location of the heaviest rain, even with only a few hours' notice." (… (24 July 2006)). The Water Information Research and Development Alliance (WIRADA) report on the "Assessment of the accuracy of NWP forecasts for significant rainfall events at the scales needed for hydrological prediction" … provides an assessment of forecast accuracy, based on an assessment of eight case studies (four in South East Queensland) over 2009-2011. It concluded that numerical weather model performance for predicting rainfall is highly variable and that none of the models were able to reproduce rapid changes in mean areal rainfall. Forecast accuracy decreased with lead time, with very little skill evident past day two. In August 2013 the BoM provided further advice reinforcing the uncertainties associated with forecast rainfall products, stating: "On some occasions, the 7 day rainfall forecast may provide some indication of the flood-producing potential of systems, but models cannot be relied upon to capture the development of every rainfall event at that timescale. In particular, the models have less skill for higher rainfall intensities and while guidance may indicate that a heavy rainfall event is possible, it is only guidance and thus, should be used in that way." … As discussed in the WSDOS Report … Section 4.1.5.3, "there may be scope in the future for the more direct use by Seqwater of BOM forecasts in the operations of the dams but this requires targeted research. ... This process would need to be progressed subsequent to WSDOS, owing to the complexity and timelines required to develop processes that would be accepted by experts."" [6]
14. To the extent that this extract and that set out in [7] constitute representations about advice received by BoM after 2011, then they could not rationally affect as assessment of the position as at January 2011. They do not constitute "recent advice". However, evidence of the representations as to the effect of the advice received from BoM prior to January 2011 could rationally affect that issue. Further, while the advice said to have been received by BoM was an opinion, the use that can be made of the fact that advice was received from BoM is a use which involves proof of a fact other than the matters asserted by the BoM (Evidence Act, ss 60 and 77).
15. However, it does not follow that this justifies the reception of the entirety of Revision 13. As noted, subsection 69(2) only effects an exception to the hearsay rule in s 59 "so far as it contains the representation". Thus, to this point all that can be tendered is so much of Revision 13 that amounts to evidence of the making of the representations as to the effect of the advice received from BoM prior to January 2011 and no more. This appears to be a pyrrhic victory for Seqwater in that the full terms of the advice received by Seqwater from BoM in 2006 and 2010 will be tendered in any event.
16. Third, Seqwater contends that Revision 13 is admissible evidence which could rationally affect the assessment of the probability of a fact in issue namely: "… the reasonableness of the approaches taken by the flood operations engineers during January 2011 and the unreasonableness in the approach for which the plaintiff contends regarding the issues of: (a) the use of rainfall forecasts in real time flood operations, including used to make advanced releases; (b) the operation of Somerset Dam in real time flood operations including use of the crest gates."
17. The relevant representations that are pointed to by Seqwater in relation to these matters are the extracts from section 4.5 above as well as section 6.2 of Revision 13 which concerns the use of the crest gates at Somerset Dam. Seqwater accepts that those representations are opinions and thus, prima facie, attract the operation of the opinion rule in s 76 (Lithgow Council). However, Seqwater contends that is not engaged given the first and second grounds of relevance demonstrate that the evidence of the opinions is relevant otherwise than as opinion evidence. [7]
18. However the only exception to the hearsay rule arising from the first and second grounds of relevance that I have accepted concerns the effect of advice received by Seqwater from BoM prior to 2011. Seqwater will be free to deploy those representations as evidence of the asserted facts and in support of the contention noted in [12(e)]. However that does not assist with the tender of the balance of Revision 13. None of the other statements in Revision 13 are capable of assisting or throwing light upon the representations as to the effect of advice received from BoM prior to January 2011.
19. It follows that so much of Revision 13 as records representations as to the advice received by Seqwater from BoM prior to 2011 will be admitted but the tender of the balance of the document will be rejected.

The WSDOS Report

1. Seqwater also seeks to tender a report entitled "Wivenhoe and Somerset Dams Optimisation Study" [8] (the "WSDOS" Report). The WSDOS Report was published by the Department of Energy and Water Supply in 2014. The WSDOS Report describes itself as an "integrated assessment of 32 potential operational options which was undertaken to assess consideration of the necessary trade-offs involving flood inundation, water supply security, dam safety, submergence of bridges and crossings, bank slumping and erosion and impacts to flora and fauna". [9]
2. Seqwater placed particular reliance on the contents of section 4.1.5 of the WSDOS report which is entitled "forecasting and early releases". Section 4.1.5.1 is entitled "Pre-emptive/advance releases" and refers to the power conferred on the Minister for Energy and Water Supply to declare a temporary full supply level under Part 3 of Chapter 4 of the Act in order to mitigate flood or drought on a case-by-case basis. The section notes that "the issue of advanced releases is linked to that of forecasting accuracy and further research is required". Section 4.1.5.2 is entitled "Use of forecasts in real time dam operations" and contains similar statements to those made in Revision 13 set out in [7]. Section 4.1.3 is entitled "future rainfall forecasts investigations" and contains similar statements about the need for further investigations before making release decisions based on forecasts as are set out in the relevant parts of Revision 13.
3. Seqwater's written submissions sought to support the tender of the entirety of the report by using the following reasoning: [10] "37 Seqwater relies upon the entirety of the WSDOS Report as evidence giving rise to a representation of fact that during the period for 2012 to 2014, that a significant change to the flood operations practices at Wivenhoe and Somerset Dams was being considered, the State of Queensland undertook a detailed study of alternative operations of the kind recommended to be undertaken in the 2006 and 2014 ICOLD Bulletins. 38 The represented fact is logically probative of the following material issues: (a) That as at January 2011, it remained the general procedure or policy of Seqwater not to make pre-releases based on forecasts for flood mitigation. (b) For that to be changed, there would need to be a study by an appropriate expert and a decision at management level to adopt a new practice, as well as changes to the Manual. (c) That as at January 2011, there had been no study by an appropriate expert and no decision at management level to adopt a new practice."
4. It can be accepted that the WSDOS Report is evidence of the representation asserted in SWS par 37. However, there is no connection between the making of that representation and so much of SWS par 38 that correctly identifies facts in issue. In particular, in relation to SWS subparagraph 38(a) it is not in dispute that as at January 2011 the flood engineers adopted the practice of not making pre‑releases based on forecasts for flood mitigation. Otherwise, the fact of the report's publication in 2014 could not rationally affect the assessment of the probability of the existence of whether that represented Seqwater's policy at that time.
5. In relation to SWS par 38(b), the fact that a WSDOS Report was obtained in 2014 could not rationally affect an assessment of the probability of whether there was a "need" for such a study by an appropriate expert before effecting some change in practice. Similarly, in relation to SWS par 38(c), the fact that the report was obtained in 2014 could not rationally affect the assessment of the probability of whether no report had been obtained in 2011 (assuming that is a fact in issue).
6. Seqwater also seeks to support the tender of the WSDOS Report by referring to the various representations within it about the necessity to undertake further research before making operational releases based on rainfall forecasts. Some of those representations have been alluded to above. Seqwater also relied on one of the recommendations in the report that there be "joint research with BoM into the potential for advanced or increased dam releases in response to seasonal forecasts". [11]
7. The reasoning said to support the admission of the WSDOS Report by reference to these statements is as follows: [12] "43 Those statements are relied upon as representations of fact that: (a) The Queensland Floods Commission made the stated recommendations regarding research into the potential use of forecasts in making release decisions including advance releases. (b) The authors of the WSDOS report also made the stated recommendations regarding research into the potential use of forecasts in making release decisions including advance releases. 44 Those representations of fact are logically probative of the following facts in issue: (a) That as at January 2011, it remained the general procedure or policy of Seqwater not to make pre-releases based on forecasts for flood mitigation. (b) For that to be changed, there would need to be a study by an appropriate expert and a decision at management level to adopt a new practice, as well as changes to the Manual. (c) That as at January 2011, there had been no study by an appropriate expert and no decision at management level to adopt a new practice."
8. Again, it can be accepted that the passages relied on by Seqwater amount to the representations referred to in SWS par 43. However, those representations and the evidence supporting them do not rationally affect the probability of the existence of so much of SWS subparagraphs 44(a) to (c) as correctly identifies facts in issue. The reasoning at [27] to [28] is equally applicable to SWS subparagraphs 44(a) and (c). In relation to subparagraph 44(b), the representations in SWS par 43 could only rationally affect the probability of the existence of that fact if they were evidence of the matters asserted by the Queensland Floods Commission and the authors of the WSDOS Report in SWS par 43. However, they are opinions and none of sections 77 to 81, especially 79, have been satisfied in relation to them (Lithgow Council).
9. Seqwater also contends that the tender of the WSDOS report could be supported by reference to the statements made in section 4.1.5.1 concerning the Minister's power to declare a temporary full supply level as noted in [25]. The reasoning said to support this is as follows: [13] "50 Seqwater relies in particular upon the statements that: (a) It is the Minister who may declare a temporary full supply level. (b) Such decisions are made in the public interest having regard to the impact of a potential temporary full supply level on water supply security, dam safety, and possible other public safety, environmental, social and economic impacts. (c) Declaring a temporary full supply level is a pre-season (or early in the season) decision and it is not intended that it be used in response to an imminent flood event. 51 Those statements are relied upon as representations of fact as to the stated approach of the State of Queensland to the use of the mechanism for setting a temporary full supply level as at 2014. Those representations are logically probative of the approach of the State of Queensland to the setting of a temporary full supply level as at January 2011. 52 Seqwater will contend that the approach of the State Government made it reasonable as at January 2011 for a competent flood operations engineer to regard the decision of whether to make releases to lower the dams below their full supply levels as a matter to be determined by the Minister, and not a matter to be decided upon during real-time flood operations by flood operations engineers."
10. To the extent that section 4.1.5.1 purports to recite the effect of the relevant legislative instruments concerning the manner in which a temporary full supply level can be declared then they are matters of law and not "facts" in issue. Otherwise, given the fact of the flood and the subsequent inquiries, then even if section 4.1.5.1 is an accurate statement of the intent of the State of Queensland in regard to an alteration of temporary full supply level as at 2014 it could not rationally affect an assessment of its position as at January 2011.
11. Finally, Seqwater seeks to support the tender of the WSDOS Report on the basis that it identifies and describes advices from the BoM as the nature, quality and utility of rainfall forecasts. The particular statements relied on are as follows: [14] "The uncertainty of forecast rainfall in terms of spatial and temporal distributions is however especially recognised (BoM 2013 PRS.Com, 30 August) as further discussed below." "BoM has previously advised Seqwater circa 2006 … and reiterated in 2010 … that their short to medium term rainfall predictions the objective use in flood forecasting models had at times considerable error or uncertainty. In correspondence received from BoM on 30 August 2013, BoM advised that it was … clear that further work was required to fully explore the use of rainfall information for dam management. …."
12. Seqwater contends that these statements rationally affect the assessment of a probability of the existence of a fact in issue, namely, its contention that "as at January 2011 recent advice from the Bureau of Meteorology did not report a change in forecasts sufficient to suggest that a reconsideration of existing practice as to use of rainfall forecasts was justified." [15]
13. The reasoning in [18] to [19] and [22] applies equally to these representations.
14. It follows that so much of the WSDOS Report as records representations as to the advice received from BoM prior to 2011 will be admitted. The tender of the balance of the document will be rejected.

16 December 2015 Report

1. Seqwater also seeks to tender a report entitled "Somerset Dam - Dam Safety Investigations - Background and Current Status" dated 16 December 2015 (the "16 December 2015 Report"). [16] The report was "reviewed and approved" by one of Seqwater's engineers, Mr Barton Maher. The report states that it summarises the contents of other structural engineering reports in relation to Somerset Dam, some of which were prepared prior to 2012 and a number of which had been prepared since 2012. The report includes a recommendation that the maximum flood storage level of Somerset Dam "be revised to a level of 107.5 mAHD" (Australian Height Datum) which is said to represent a point at which Somerset Dam "is likely to have a high probability of failure". [17]
2. Seqwater contends that these statements amount to "representations of fact that as at 16 December 2015 the state of knowledge of Seqwater regarding the safety of Somerset Dam was that the safe maximum flood storage level was 107.5 mAHD and not 109.7 mAHD", [18] the latter being the height referred to by the plaintiff's experts. Seqwater contends that that representation could rationally affect the assessment of the probability of the existence of the following facts in issue in the proceedings, namely, whether: [19] "(a) … as at January 2011 the precise water level for Lake Somerset at which the water would causes Somerset Dam to become unstable and fail was not known; (b) … as at January 2011 if the level of water in Somerset Dam (exceeded) 107.46 mAHD the breezeway would be overtopped and the ability of Somerset Dam or its abutment and foundations to withstand flood loads becomes increasingly uncertain."
3. I do not accept that the tender of the 16 December 2015 Report could rationally affect an assessment of the probability of (a). At most, the 16 December 2015 Report simply amounts to a representation as to Seqwater's understanding as at 2015. In light of the contents of the report which refers to knowledge gained from other reports prepared after January 2011, that representation could not affect the assessment of its state of knowledge as at January 2011. In relation to (b), that representation could only rationally affect an assessment of that matter if it is taken to be evidence of the matter asserted, namely, that the safe maximum flood storage level is 107.5 mAHD. Properly analysed, that assertion is a matter of opinion and could only be supported if a relevant exception to the opinion rule was made out. Notwithstanding that Mr Maher has some qualifications as a hydrologist and design engineer, the report does not satisfy the requirements of s 79 of the Evidence Act as outlined in Dasreef Pty Ltd v Hawchar [2011] HCA 21.
4. Seqwater also seeks to tender the document on the basis that the representations noted in [39] above could rationally affect an assessment of whether the approach apparently taken by the flood operation engineers during the flood event to leave open the Somerset Dam crest gates was reasonable and that the simulated operations conducted by the plaintiff's experts, which involved closing the crest gates at dam levels as high as 106.5 mAHD, was unreasonable [20] . However, the evidence of those representations could only have that consequence if it is taken to be evidence of the matter asserted, namely, that the "safe maximum flood storage level was 107.5 mAHD" which, for the reasons just stated, it is not.
5. Accordingly, I reject the tender of the 16 December 2015 Report (and the reports referred to in it that were prepared after January 2011).

The 17 December 2015 Report and the Alternative Procedure for Somerset Dam

1. Seqwater seeks to tender a report dated 17 December 2015 entitled "Assessment of Somerset Dam Flood Operations for Dam Safety" [21] as well as a document entitled "Alternative Procedure Under Section 4.6 of the Manual for Operational Procedures for Flood Mitigation at Wivenhoe Dam and Somerset Dam Revision 13 November 2015" [22] . The first of these reports builds on the Dam Safety Report which has already been rejected. It considers options for amending the flood operations procedures for Somerset Dam and recommends that those procedures should maximise the outflow from the dam during flood events without regard to the impact on Wivenhoe Dam lake levels. Associated with this is the alternative procedure which is a pro forma document ready to be signed by a Senior Flood Engineer for submission to a Dam Safety Regulator. If it is approved it allows Somerset Dam to effectively act as "ungated" dam. Seqwater contends that this method of operating Somerset Dam is fundamentally inconsistent with what the plaintiff's expert contends was required of the reasonably competent flood operations engineer operating Somerset Dam during the flood event.
2. Seqwater contends that these documents amount to statements as to the flood operation practices at Somerset Dam as at December 2015 and thus it is said they fall within the scope of the ruling in Rodriguez (No 11) noted above. It can be accepted that they amount to statements concerning (at least the alternative) flood operations practices at Somerset Dam as at December 2015. However, for the reasons already outlined, the ruling in Rodriguez (No 11) does not assist their tender in circumstances where there is reason to believe that there have been dramatic changes since January 2011.
3. Seqwater also seeks to support the tender of these documents by contending they are evidence that could rationally affect the assessment of the probability of the existence of a fact in issue, namely, the "reasonableness of the approach taken by the flood operation engineers for the operation of Somerset Dam crest gates during January 2011" and the "unreasonableness of the approach to the operation of the Somerset Dam crest gates in Dr Christensen's simulations". [23] These documents are only evidence of that matter if the relevant representations within them as to the procedures to be adopted, represent evidence of the correct procedures that had to be adopted as at January 2011. There are numerous difficulties with that contention including that such a representation is an opinion and no relevant exception to the opinion rule has been made out by Seqwater.
4. Accordingly, the tender of these documents is rejected.

Gazettal Notice

1. Seqwater seeks to tender an extract from the Queensland government gazette dated 22 January 2016 recording a declaration of temporary full supply levels for Wivenhoe Dam and Somerset Dam. [24]
2. The reasoning Seqwater seeks to deploy to support the tender is as follows: [25] "Seqwater relies on the Gazettal notices as representations of fact that: (a) The mechanism adopted for modification of the full supply levels of the dams was gazettal of a decision by the Minister under s. 395 of the Water Supply (Safety and Reliability) Act 2008; (b) The Minister made the decision modifying the full supply levels of the dams having had regard to "the feasibility advice and the public interest" as stated in the notices. Both representations are logically probative of the reasonableness of a competent flood operations engineer in January 2011 regarding the decision of whether to make releases to lower the dams below their full supply levels as a matter of policy to be determined by the Minister, and not a matter to be decided upon during real-time flood operations by a flood operations engineer."
3. To the extent that the gazettal notice records the existence of the mechanism for modifying full supply levels, namely the conferral of a power on the relevant Minister by s 395 of the Act, then it is does not relate to a "fact in issue" but simply a matter of law that may or may not be in dispute. To the extent that the gazettal notice records the making of a decision by the Minister in 2016 and the considerations taken into account then it could not rationally affect the assessment of the probability of the existence of any of the matters noted in [48].

Conclusion

1. So much of Revision 13 and the WSDOS report which record representations as to the advice received by Seqwater from the Bureau of Meteorology prior to January 2011 will be admitted. The tender of the balance of those documents and the other documents listed in Annexure A is rejected.
2. The Court orders that: (1) Within 7 days, Seqwater prepare redacted versions of Revision 13 of the Manual (SEQ.004.041.1834) and the WSDOS Report (SEQ.004.041.3589) consistent with this judgment.

ANNEXURE A Documents DOC ID Report SEQ.004.036.7520 Somerset Dam Safety Review (17 March 2014) Report Seqwater Dams Portfolio Risk Assessment SEQ.004.036.7950 Dam Safety risk Management Strategy (22 November 2013) Report Seqwater Dams Portfolio Risk Assessment SEQ.004.036.8522 Somerset Dam (1 November 2013) Somerset Dam Dam Safety Investigations SEQ.004.041.0700 Background and Current Status Report Somerset Dam Flood Upgrade Options Feasibility Study SEQ.004.041.0731 Interim Report (November 2014) Seqwater Review of Seqwater Dams SEQ.004.041.1205 Expert Review Panel Report No 7 Seqwater Somerset Dam SEQ.004.041.1230 Engineering Geological Study (11 December 2015) Seqwater Somerset Dam SEQ.004.041.1414 Additional Stability Analyses (December 2015) Assessment of Somerset Dam Flood Operations for Dam Safety (17 December 2015) SEQ.004.041.1469 Alternative Procedure under Section 4.6 of the Manual for Operational Procedures for Flood Mitigation at Wivenhoe Dam and Somerset Dam, Revision 13, November 2015 SEQ.004.041.1633 Queensland Government Gazette No 11 (22 January 2016) SEQ.004.041.1833 Manual of Operational Procedures for Flood Mitigation at Wivenhoe Dam and Somerset Dam (November 2015) SEQ.004.041.1834 Report Seqwater Dams Portfolio Risk Assessment SEQ.004.041.1943 Wivenhoe Dam (1 November 2013) Seqwater Somerset Dam Flood Upgrade Options Feasibility Study SEQ.004.041.2672 Upstream Impact Assessment Report (July 2015) Seqwater Somerset Dam SEQ.004.041.2720 Supplemental Stability Analyses (April 2016) Seqwater Somerset Dam Flood Upgrade Options Feasibility Study - Final Report (February 2015) SEQ.004.041.3324 Wivenhoe and Somerset Dams Optimisation Study Report SEQ.004.041.3589

Endnotes

1. 5/Tab 12; SEQ.004.041.1834.
2. SEQ.004.041.1834 at 1857.
3. Seqwater Written Submissions provided 18 April 2018 ("SWS") at par 14(b).
4. SWS at par 12.
5. SWS at [18].
6. SEQ.004.041.1834 at 1857.
7. SWS at par 29.
8. SEQ.004.041.3589.
9. SEQ.004.041.3589 at 3610.
10. SWS at pars 37 to 38.
11. SWS at par 42.
12. SWS at pars 43 to 44.
13. SWS pars 50 to 52.
14. SWS at par 58.
15. SWS at par 59.
16. SEQ.004.041.0700.
17. SEQ.004.041.0700 at 0701.
18. SWS at par 70.
19. SWS at par 71.
20. SWS at par 75.
21. SEQ.004.041.1469
22. SEQ.004.041.1633
23. SWS at par 85(b).
24. SEQ.004.041.1833.
25. SWS at pars 94 to 95. DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated. Decision last updated: 02 May 2018