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

Background

1. The hearing of these proceedings commenced in December 2017 and continued throughout most of 2018. Save for the remaining submissions on the evidence of the subject of this judgment and Rodriguez (No 18), the final oral submissions took place in November and December 2018.
2. Rodriguez (No 18) was published on 30 November 2018. I allowed, in part, an application by the plaintiff, Rodriguez & Sons Pty Ltd ("Rodriguez"), to adduce further expert evidence from Dr Altinakar. During the course of the final oral submissions in December 2018, I fixed 19 March 2019 for the cross‑examination of Dr Altinakar on his further evidence. I also made orders for the service of any proposed material in response to his further report from any of the three defendants by 1 March 2019.
3. The third defendant, the State of Queensland (the "State"), did not serve any further material. Seqwater served a report from a senior engineer, Dr Luke Toombes, dated 15 February 2019. SunWater served a report by Dr Sharmil Markar dated 21 February 2019. The Court fixed 11 March 2019 for the hearing of the plaintiff's objection to the tender of those reports in anticipation of a ruling being given sufficiently in advance of 18 March 2019, so as to allow the balance of the evidence and submissions in the proceedings to be completed at that time.

Rodriguez (No 18)

1. As the outcome of this application is largely determined by the findings in Rodriguez (No 18), it is necessary to describe that judgment in detail.
2. Over time, Dr Altinakar has prepared a number of two‑dimensional mathematical hydraulic models of the Greater Brisbane area which are meant to replicate the flow of water during the flood event in early January 2011. His modelling is also said to demonstrate what would have been the extent of flooding in areas of size 10m x 10m, had different outflows from the Wivenhoe Dam occurred that corresponded with what the plaintiff contended were non‑negligent dam operations (Rodriguez (No 18) at [4]).
3. The course of events that led to the tender of (redacted versions) of further reports from Dr Altinakar as allowed in Rodriguez (No 18) was as follows: "7 Revised reports from Dr Altinakar were served between August 2017 and October 2017. They included a report dated 16 October 2017 addressing various issues raised concerning the calibration of his model and which presented the result of his revised modelling of the actual flood event. They also included a report dated 31 October 2017 which presented the results of his modelling of Dr Christensen's ten scenarios. 8 In his 16 October 2017 report, Dr Altinakar explained that the "revised model contains a number of modifications" to his earlier modelling following the inclusion of better-quality data received in a data package produced by the BRCFS. [1] He said he used the "the latest hydrologic simulation results that were provided in the BRCFS Data using the 'Aurecon URBS model'". [2] The "Aurecon URBS model" is a model developed by Aurecon as part of the BRCFS. However, for one of the revised inflow boundaries known as "Rifle Range Road Alert" he included a hydrograph indicating that he had sourced the data from a column entitled "locky_RIFLE_RA-Recd" in an Excel spreadsheet, namely "locky_tot.q". [3] 9 ……. 10 A directions hearing was held on 27 November 2017 just prior to the commencement of the hearing. At the directions hearing there was a discussion about the time it would take to serve material in response to Dr Altinakar's revised reports. Both Seqwater and the second defendant, SunWater Ltd ("SunWater"), stated that they anticipated being able to file material by the middle of February 2018 [4] whereas the State suggested it should be able to serve its material during December 2018. 11 The hearing commenced on 4 December 2017 with two weeks of opening addresses. It was then adjourned until 19 February 2018 when the plaintiff's evidence commenced. In the meantime, the Court conducted a view. 12 On or about 18 January 2018, the State served a further report from Mr Neil Collins dated 21 December 2017 which responded to Dr Altinakar's revised reports. In relation to tributary inflows (which include Lockyer Creek), Mr Collins referred to Dr Altinakar's use of the local tributary inflows from the BRCFS and stated that Dr Altinakar's reports "adequately addressed my concerns in that regard as expressed in my May 2017 report". [5] 13 On 19 February 2018, the plaintiff's solicitors emailed the solicitors for Seqwater and SunWater to ascertain if there was any material being provided in response to Dr Altinakar, noting that "Dr Altinakar will need to be given enough time to absorb the evidence before he is cross‑examined". 14 On 1 March 2018, Seqwater's solicitors responded stating "[w]e advise that Mr Babister will not be called to give evidence" and "[a]ccordingly, [we do] not intend to serve any evidence in response to Dr Altinakar". 15 On 14 March 2018, SunWater advised that it did not intended to serve any evidence in response to Dr Altinakar. 16 In the meantime, the hearing continued. Dr Altinakar is a resident of the USA. Arrangements were made for him to attend for cross‑examination on 11 April 2018. However, early on the morning of 10 April 2018, Seqwater served an affidavit from one of the flood engineers, Mr Malone, sworn 9 April 2018. [6] In that affidavit Mr Malone explained that, "[a]s part of my role as a Hydrologist Specialist at Seqwater", he had access to two data packages including one that contained the Aurecon URBS Model. He referred to Figure D-38 from Dr Altinakar's 16 October 2017 report and explained that the "discharge hydrograph represents the rated flow rate at the site of the Rifle Range Road gauge" and did "not represent the flow rate at that site as calculated by the Aurecon URBS Model". In broad terms, a rated flow is a flow calculated from a measured height of a waterway. Mr Malone extracted part of the rating which warned that the rating should not be used if the Lockyer Creek was above 15.5m, which it was during the peak of the January 2011 flood event. 17 Mr Malone then extracted the "Lockyer Creek vector" from the Aurecon URBS Model and explained how that "vector" split and modelled the flows into and out of Rifle Range Road Alert. [7] His affidavit then states: [8] "I added a statement "PRINT.FPB C" to the model vector immediately after INPUT.FPB C. This generated the hydrograph labelled FPB_C in the model output files. The sum of the calculated main channel flow (shown in the blue dashed line on the figure below - 850m3/s) and the bypass floodplain flow (shown in the purple dashed line on the figure below - 3,58m3/s) will then give the total flow calculated by the Aurecon URBS Model passing the Rifle Range Road gauge (RIFLE_RANGE_RD (C) + FPB_C (C) = 4,431m3/s) as shown in red in the figure below, which also presents the rated flow in green (3670m3/s)." 18 Mr Malone then set out a hydrograph showing the difference between the rated and calculated flows at this point. 19 Even though the text of Dr Altinakar's reports runs to in excess of 1000 pages, he was only cross‑examined for a day and half. It is not necessary to describe the cross‑examination of him by Senior Counsel for SunWater or the State. The cross‑examination of Dr Altinakar by Senior Counsel for Seqwater concerned two points, namely, the appropriateness of Dr Altinakar's reliance on the rated flow figures at Rifle Range Road Alert rather than the calculated flows and the inflow figures he used at a boundary to his model on the Bremer River. In relation to the former, Dr Altinakar explained that he understood the difference between the rated flow and calculated flow but could not interpret the calculated flow data because the model was diverting all flow above 850m3/s through a hypothetical channel. [9] He said that he could not determine where the diverted flow re-joined the model because "it was very difficult, unless you know exactly the language of the Aurecon model itself" which he did not. [10] Critically, he stated that he could not ascertain what the balance of the flow above the 850m3/s was ("[w]e couldn't understand it from the data that was given to us in terms of the model"). [11] 20 Dr Altinakar was cross‑examined on Mr Malone's affidavit for some time. [12] Dr Altinakar stated that he had only received it the day before he gave evidence. [13] Based on Mr Malone's interrogation of the model as revealed in his affidavit, a difference of 761m3/s between the calculated flow and rated flow could be discerned. [14] The cross‑examiner then suggested to Dr Altinakar that a difference in peak flow of 761m3/s could not be dismissed as immaterial. [15] Dr Altinakar responded that it was "[v]ery difficult to say" but he "would guess that as you would go more and more downstream, the effect would be negligible, practically". [16] 21 The significance of all this is that it demonstrates beyond any doubt that Mr Malone's affidavit was truly "evidence in response" to Dr Altinakar. It was served one day prior to his scheduled appearance in circumstances where Seqwater had previously advised the plaintiff that no such evidence would be relied on. This is a very significant matter in the context of this application. 22 Dr Altinakar finished his evidence on 12 April 2018 and presumably returned to the USA shortly thereafter. The plaintiff then closed its case subject to the tender of the material. The hearing then continued with the defendants' cases. 23 On 26 April 2018, a further report was served from Mr Collins by the State which retracted his satisfaction with Dr Altinakar's use of tributary inflows and asserted the flow differences were "material to the modelling simulations carried out by Dr Altinakar on the dam operation scenarios by Dr Christensen". [17] The report sought to expand on that assertion by reference to the BRCFS, however, in circumstances where its reports and modelling were not being tendered those parts of Mr Collins' report were rejected (Rodriguez & Sons Pty Ltd v Queensland Bulk Water Supply Authority trading as Seqwater (No 16) [2018] NSWSC 1223). 24 By August 2018 the end of the oral evidence was coming into view as the defendants announced that various witnesses would not be called. On 1 August 2018 there was a brief discussion about the scope of Mr Collins' reports and the objections to it. During that discussion I queried with Junior Counsel for the plaintiff whether there would be an attempt to redo Dr Altinakar's modelling with the revised inflow figures. Counsel indicated that "at this stage of the evidence, no". He explained that, in the absence of any modelling from Mr Collins, they were content to rely on Dr Altinakar's answers as to the lack of materiality of the different figures. [18] 25 On 2 August 2018, a solicitor acting on behalf of the plaintiff contacted Dr Altinakar to request that he undertake revised modelling using the alternative discharge hydrographs for Rifle Range Road Alert and the Bremer River. [19] 26 On 6 August 2018, I published rulings on the objections to Mr Collins' report and the reasons for those rulings (Rodriguez & Sons Pty Ltd v Queensland Bulk Water Supply Authority trading as Seqwater (No 16) [2018] NSWSC 1223), aspects of which are recounted above. Two matters should be noted about the judgment. 27 First, I observed that the differences between the rated and calculated flows were raised in cross-examination with Dr Altinakar and he had the opportunity to respond (at [5]). Having reviewed these events in more detail, that finding should only be understood as stating that Dr Altinakar had an opportunity to respond to the difference in the figures in cross‑examination. He did not have a proper opportunity to consider the flow differences, model their effect and most importantly reflect upon why one should be preferred over another. 28 Second, I observed as follows (at [6]): "I would add otherwise that I have already, and continue to, express some disquiet about the proposition that something that could be potentially so important to the case as to the materiality of discrepancies in the inflows modelled by Dr Altinakar will simply turn upon one party or another pointing to the uncertainty or otherwise surrounding its materiality, rather than simply having Dr Altinakar's simulations take into account what the defendants say are the correct inflow figures and then leaving it to the Court to determine what are the figures that should be adopted." 29 Mr Collins was cross‑examined on 8 August 2018. Perhaps unwisely, the cross‑examination tested his assertions about materiality. [20] There is a debate in the substantive submissions about whether the overall effect of Mr Collins' evidence concerning these inflows is sufficient to warrant the Court rejecting the reliability of Dr Altinakar's modelling. 30 On 10 August 2018, a solicitor acting for the plaintiff wrote to Seqwater's solicitors seeking the spreadsheet figures underlying the hydrograph of the calculated flows set out in Mr Malone's affidavit sworn 9 August 2018. [21] Four days later the solicitors responded refusing to provide the material requested on the basis that they anticipated it was sought to be used in support of a reopening application. [22] This was an unfortunate response especially when considered in the context of the earlier email sent on 1 March 2018. 31 By a letter dated 11 September 2018, the plaintiff's solicitors advised the other parties that it proposed to rely on further modelling from Dr Altinakar that incorporated the calculated flows at the Rifle Range Road Alert boundary condition and further flows from the Bremer River and also model the revised gate operations under the Ickert Variation. [23] Their letter explained that the plaintiff's position was that the revised modelling to take into account the revised boundary inflows was not necessary in light of the evidence about materiality but it would be adduced in the event that the defendants sought to submit that the modelling was unreliable because of this dispute. The Court was advised of this on 14 September 2018. Directions were made for the service of the material as well as submissions and affidavits concerning the plaintiff's application to tender the further reports from Dr Altinakar. Revised Report 1 and Revised Report 2 were served on or about the date they bear."
4. Paragraphs [19] to [20] of the above summarise the evidence given by Dr Altinakar on 11 April 2018. In submissions on this application, Senior Counsel for Seqwater, Mr O'Donnell QC, emphasised that part of the oral evidence of Dr Altinakar on 11 April 2018 in which he agreed that the Aurecon/URBS hydrological model "was likely to produce more reliable results than the unreliable rated flows". [24] However, as the above description makes clear, the only specific difference between the two flows that Dr Altinakar was cross‑examined upon was the difference of 761m3/s in peak flows between the rated flows and Mr Malone's hydrograph. That is the only difference relied on in Seqwater's final written submissions. [25]
5. There were two reports of Dr Altinakar the subject of the application determined by Rodriguez (No 18). [26] In combination, the two reports addressed four topics. The first topic was the recalibration of Dr Altinakar's existing model (the "2017 Set up") to take into account Mr Malone's hydrograph and a revised inflow discharge hydrograph for the Bremer River producing a new model set up (the "2018 Set up"). The second topic was the outcome of the application of the 2018 Set up to Dr Christensen's ten counter‑factual simulations and five variations on that those simulations that derive from the report of one of Sunwater's experts, Mr Andrew Ickert (the "Ickert variations"). The third topic was the application of the 2017 Set up to the five Ickert variations. The fourth topic was that Dr Altinakar addressed whether it was appropriate to use the inflow discharge figures for Lockyer Creek immediately upstream of the Rifle Range Road Alert that were suggested to him in cross‑examination, i.e., Mr Malone's hydrograph.
6. As noted, Seqwater advised the plaintiff on 1 March 2018 that it did not propose to serve any evidence in response to Dr Altinakar's October 2017 reports and models, yet it did exactly that on the day before he gave oral evidence. Accordingly, in Rodriguez (No 18), I found that "the course of events up until 10 April 2018 conveyed to the plaintiff that there was no issue being taken with Dr Altinakar's use of tributary inflows". [27]
7. In addressing Rodriguez's application, I "treated" it as an "application to re-open" as opposed to an application to call evidence in reply and applied the principles apposite to the former. [28] I rejected the application so far as it concerned the first and second topics of Dr Altinakar's further reports noted above, i.e., so much of Dr Altinakar's further reports that addressed the materiality of changing the flows to accord with Mr Malone's hydrograph and which yielded the 2018 set up. [29] Critical to that decision was a finding that "the course of events from 26 April 2018 to early August 2018 reveal[ed] … a deliberate decision [was made by Rodriguez] ... not [to] seek to prove the immateriality of any alteration of the inflows at the boundaries on the Lockyer [Creek]" to reflect Mr Malone's hydrograph. [30] I noted that, as "all the parties [had] made careful and deliberate decisions about the extent to which they would address the materiality of the differences of inflows at the two boundary conditions", to now allow that issue to be litigated could lead to substantially more hearing time and expense. I concluded that the interests of "finality in inter‑parties litigation" warranted the rejection of this aspect of the evidence. [31]
8. The evidence of Dr Altinaker concerning the third topic was admitted, [32] however, that is irrelevant to this application. In relation to the fourth topic of Dr Altinakar's further reports, i.e., his explanation for preferring his boundary inflow figures at Rifle Range Road, I found that "the course of events [had] occasioned an unfairness to the plaintiff in effectively denying to Dr Altinakar a proper opportunity to respond to the suggestion that he should have used [Mr Malone's] calculated figures for the inflow boundary on Rifle Range Road". [33] I found that, "[i]f Dr Altinakar had received Mr Malone's affidavit, including the spreadsheet underlying the hydrograph, at the time the plaintiff was pressing for responsive material, then he would have had a reasonable opportunity to reflect upon the suitability of the use of those inflow figures and address it in his evidence on 11 April 2018". [34] I also found that, to "allow the tender of material from Dr Altinakar explaining his preference for the inflow figures used in the 2017 Setup, would not involve granting the plaintiff any liberty to revisit any deliberate decision it made to not prove (or further prove) the immateriality of the different flows on the flooding outcome" but instead "would be consistent with that decision". [35]
9. In relation to any prejudice occasioned by the tender of this aspect of Dr Altinakar's revised reports I found as follows: [36] "None of the parties specifically addressed the prejudice that would be occasioned by a decision to admit only this aspect of Dr Altinakar's revised reports. Given that it would not involve the plaintiff being able to revisit its decision not to prove (or further prove) immateriality it is difficult to see how either Seqwater or SunWater would be permitted to serve any responsive evidence. It is possible that the State might be permitted to call evidence from Mr Collins to address this issue, but I expect that evidence would be limited in scope. Overall, I am satisfied that, if this material is allowed, there is likely to be some further hearing time and preparation necessary but I expect it will be limited. This will occasion some delay and expense but that does not outweigh the unfairness that I have identified." (emphasis added)
10. If it is not otherwise obvious, the reason that I had difficulty in envisaging that either Seqwater or Sunwater would be permitted to serve responsive evidence was that both had made "careful and deliberate decisions" not to rely on affidavit evidence in response to Dr Atlinakar's October 2017 reports and modelling. To give effect to the necessity for finality in the conduct of litigation, Rodriguez (No 18) envisaged all parties being held to the forensic decisions they had previously made in relation to the service and non-service of evidence. The only exception to that relevant to this topic was that Rodriguez was permitted to adduce limited further evidence from Dr Altinakar (solely) to address the unfairness that arose from the late service of Mr Malone's affidavit.

Dr Altinakar's Redacted Reports

1. Redacted versions of Dr Altinakar's reports were prepared and tendered. [37] The redactions gave effect to the rulings in Rodriguez (No 18). Leaving aside the Ickert variations, Dr Altinakar referred to the hydrograph set out in Mr Malone's affidavit and stated that he assumed that it represented the hydrograph produced by the Aurecon/URBS model for Rifle Range Road. [38] Senior Counsel for Rodriguez, Mr Owens SC, submitted that, in light of a hydrograph set out in Dr Toombes' report, there is reason to believe that Mr Malone's hydrograph incorrectly shifts the peak flow predicted by the Aurecon/URBS model nine hours earlier in time. [39] It is unnecessary to consider that further at this point.
2. In his redacted reports, Dr Altinakar explained his understanding of the Aurecon/URBS model and, in particular, his understanding that the model is "calibrated to specific 'main calibration locations' within the Aurecon/URBS model" but that it does not model the "true flows for each location or sub-area in that model". [40] Dr Altinakar noted that the States' expert, Mr Collins, used the Aurecon/URBS model of flows at O'Reilly's Weir to "represent the discharge from Lockyer Creek into the Brisbane River". [41] Dr Altinakar also noted that Mr Collins supposedly affirmed the O'Reilly's Weir data because it was a specified input into the BRCFS hydraulic model. [42] O'Reilly's Weir is located on the Lockyer Creek downstream of Rifle Range Road and immediately upstream of the confluence of Lockyer Creek and the Brisbane River. All the modelling appears to direct water from the Lockyer Creek catchments, including its flood plains, through O'Reilly's Weir and into the Brisbane River. [43]
3. Dr Altinakar then stated that the sum of the peak flows he used for Rifle Range Road and the catchments between that point and O'Reilly's Weir (4682m3/s) "more closely matches" the peak flow at O'Reilly's Weir according to Mr Collins figures (4373m3/s) than the equivalent figure derived from using Mr Malone's hydrograph (5352m3/s). [44] He also noted that his modelling (i.e., the 2017 Setup) calculated a peak flow for O'Reilly's Weir (4331m3/s) which he considered matched well against Mr Collin's figure (4373m3/s). [45] Dr Altinakar concluded: [46] "In light of this analysis, I conclude that my 2017 Setup did not significantly underestimate the true … Lockyer Creek discharges during the January 2011 Brisbane Flood. Furthermore, in light of this analysis, I do not think it is correct to assume that the discharges at Rifle Range Road were those shown in Mr Malone's hydrograph."
4. One step in this reasoning is Dr Altinakar's assumption that the Aurecon/URBS model data for O'Reilly's Weir represents the discharge from Lockyer Creek into Brisbane River during the January 2011 Flood Event. [47] In that regard, I note that in July 2018 the Court requested each of the parties to advise of their respective position concerning the flows at Lowood without any releases from Wivenhoe Dam from 2 January 2011. Lowood is on the Brisbane River just downstream of its confluence with Lockyer Creek. The State responded to this request by stating that "[a]ssuming no releases from Wivenhoe Dam, the flow at Lowood is predominantly the flow emanating from Lockyer Creek, which enters the Brisbane River a short distance upstream" and that the "approximate peak flow from Lockyer Creek in the 2011 event is 4,400m3/s". [48] The State's response added "see Mr Collins' October 2017 correction report". [49] It was accepted that this was a reference to his April 2018 correction report which relevantly stated that "Figure 3‑1 of [my] report [dated May 2017] shows … predicted inflows from the BRCFS model for Lockyer Creek … with peak flows of … 4,400m3/s for Lockyer Creek." [50] The hydrograph in Figure 3‑1 of Mr Collins' May 2017 report is the BRCFS hydrograph for O'Reilly's Weir. [51] Both Seqwater [52] and Sunwater [53] adopted the State's response. On its face, this appears to be an adoption of the O'Reilly's Weir hydrograph as representing the flows out of Lockyer Creek into the Brisbane River.

Dr Toombes' Report

1. Dr Toombes' Report contains a lengthy discussion of the Aurecon/ URBS hydrological modelling generally, as well as its modelling of the Lockyer Creek flows in particular. He expresses a preference for the modelled flows at Rifle Range Road. He is critical of Dr Altinakar's comparison exercise described in [17] partly because it does not account for the difference in the arrival of the timing of the peak flows at Rifle Range Road, bearing in mind attenuation. [54]
2. Three matters should be noted about Dr Toombes' report
3. First, in his executive summary, Dr Toombes states that the Aurecon/URBS model "replicates as closely as possible flow hydrographs at Glencore Grove and at Savages Crossing on the Brisbane River". However, he does not make the same statement in relation to either Rifle Range Road (as it was not a calibrated flow point) or in relation to O'Reilly's Weir. Instead, with the former he concludes that the modelled flows "are significantly more reliable than the rated flows at this location". [55] With the latter, Dr Toombes merely states that O'Reilly's Weir was "hydrologically and hydraulically complex and inconsistent" and disputed that its hydrograph was an input into the BRCFS hydraulic model. [56] Later in his report, he states that he has "confidence" in the flows at O'Reilly's Weir but added that it "is submerged by the Brisbane River during dam releases and flows must be more reliably … confirmed further downstream in the Brisbane River". [57]
4. In relation to Rifle Range Road, Mr Owens SC pointed to parts of Dr Toombes' report which he contended purported to contradict earlier evidence from Mr Collins as to the accuracy of the Aurecon/URBS model flows at points between the calibrated locations, such as Rifle Range Road. [58] Mr Owens SC submitted that this raised a "whole new argument" about the construction of the Aurecon/URBS model which was inconsistent with the evidence of Mr Collins and the manner in which all of the defendants ran their cases. [59]
5. In relation to O'Reilly's Weir, Mr Owens SC submitted that the effect of Dr Toombes' report is to effectively contradict Mr Collins' evidence concerning the reliability of the Aurecon/URBS flow hydrograph at that point. [60] As noted, Mr Collins put that hydrograph forward without qualification and the defendants appear to have adopted it. There is some dispute as to whether Mr Collins stated that it was an input into the BRCFS hydraulic model and, if so, whether he was correct. [61] However, leaving that aside, Seqwater disputed that it and Dr Toombes were challenging Mr Collins' evidence concerning the reliability of the Aurecon/URBS hydrograph at O'Reilly's Weir. [62] However, although it is not clear, it appears implicit in Dr Toombes' report that he has misgivings about the reliability of the O'Reilly's Weir hydrograph produced by the Aurecon/URBS model (see [21]).
6. Second, in his discussion of Dr Atlinakar's comparison of the rated flow and Mr Malone's hydrograph, Dr Toombes does not confine himself to responding to Dr Altinakar's comparison of the peak flows. He also compares the "shape and timing" of the two hydrographs. [63] Mr Owens SC submitted that this involved an unfair expansion of the issues given that the point made in the cross‑examination of Dr Altinakar concerned the comparison of peak flows and that is what he responded to in his further report. [64]
7. Third, one part of Dr Toombes' report drifts into addressing the materiality of the difference between Mr Malone's flows and the rated flows. Thus he states that "changing the coincident peak, and indeed full hydrograph, would affect the resulting representation of 2011 flood flows used to calibrate the hydraulic model", although he added that he had not "investigated the effect and therefore cannot comment on by how much". [65]

Dr Markar's Report

1. Mr Owens SC made a number of points in relation to Dr Markar similar to those raised in relation to Dr Toombes. [66] I note three of them.
2. The first question asked of Dr Markar was whether Dr Altinakar's assumption that the hydrograph data for O'Reilly's Weir produced by the Aurecon/URBS model was reasonably reliable a sound assumption. Dr Markar answered that the assumption was not sound. [67] As noted, that is inconsistent with Mr Collins' evidence and appears to be inconsistent with the response to the Court's inquiry of the parties noted above.
3. Second, Dr Markar concluded that Dr Altinakar's inflow boundary condition was not appropriate, partly because the location of the adopted upstream condition was inappropriate. [68] Dr Markar stated that, if Dr Altinakar had used Glencore Road as the boundary condition, that would have "eliminated the major shortcomings in [the 2017 setup] associated with the chosen Lockyer Creek upstream boundary condition". [69] In his October 2017 report, Dr Altinakar explained that he had moved the boundary of his model from O'Reilly's Weir to Rifle Range Road to address concerns raised in the reports of the defendants' experts addressing his earlier modelling. [70] The issue of the location of the boundary condition was not revisited in any subsequent report. It was not suggested to Dr Altinakar in cross‑examination that he used an inappropriate location for the boundary to his model and Mr Collins did not state that either. Mr Owens SC submitted that this was revisiting an issue that had effectively been abandoned and if he were to respond, Dr Altinakar would be entitled to revise his boundary condition. [71]
4. Third, like Dr Toombes, part of Dr Markar's analysis is that Dr Altinakar should not have limited himself to just comparing the peak of the hydrographs at Rifle Range Road but should have also considered the "shape, timing … and volume of the hydrograph". [72] Also, like Dr Toombes, Dr Markar expressed views on the materiality of an under estimate of the "true Lockyer Creek discharges". [73]

The Reports Must Be Rejected

1. In his written outline, Mr Owens SC objected to the tender of the entirety of Dr Markar's report and Dr Toombes' report on four bases. First, he contended that the reports "go beyond a response to the 2018 Altinakar reports and raise new criticisms" of Dr Altinakar's modelling and reports. Second, he submitted that in substance they are directed to attacking or at least undermining the evidence of Mr Collins. Third, he submitted that they otherwise seek to "impermissibly expand the scope of the controversy [between the parties] with respect to the inflows at Rifle Range Road". [74] However, these matters are just aspects of his fourth objection, which is that to allow these reports would be inconsistent with the scope of the leave granted in Rodriguez (No 18) to adduce further evidence from Dr Altinakar and the reasons for that grant of leave. [75] Mr Owens SC submitted that, as Rodriguez (No 18) only conferred a limited grant of leave to adduce further evidence to rectify an unfairness but otherwise held the parties to their forensic decisions, the appropriate analysis was to consider the position had that unfairness not occurred. [76] On that approach, Dr Altinakar would have given his (limited) response to Mr Malone's affidavit and the points raised with him in cross‑examination, and neither Seqwater or Sunwater would have been granted leave to reconsider their decisions to rely on evidence in response. [77]
2. I have summarised the reports the subject of the proposed tender. At one level of generality they are responsive to Dr Altinakar's further reports in that they seek to rebut Dr Altinakar's contention that the flows at Rifle Range Road he utilised in the 2017 Set up were preferable to Mr Malone's hydrograph. However, it is also correct that they raise a range of matters that either could and should have been raised in response to Dr Altinakar's October 2017 reports and modelling, or which are beyond what Dr Altinakar was permitted to address, such as materiality, or both. Overall, I have no doubt that, if the tender of these reports was permitted, then considerations of fairness would dictate that the plaintiff would be entitled to have Dr Altinakar undertake a more fulsome response, including one that addressed materiality by, for example, the tender of the 2018 Set up [78] . Put another way, to allow the tender of this material would in effect be a grant of permission to the defendants to revisit their forensic decisions in relation to Dr Altinakar. In that event, fairness would dictate that Rodriguez be allowed to do likewise.
3. Senior Counsel for SunWater, Mr Williams SC, submitted that the tender of Dr Markar's report should be treated on the basis that, in Rodriguez (No 18), I allowed the plaintiff leave to re-open as opposed to granting them leave to adduce evidence in reply. [79] On that basis, he contended that allowing the plaintiff leave to reopen carries with it a correlative right on the part of the defendants to adduce evidence in response, even if that responsive evidence potentially raises new issues or traverses forensic decisions previously made by the defendant. [80]
4. I reject that submission. The scope of the permitted response to Dr Altinakar's further reports is not to be ascertained from characterising whether the further (redacted) reports of Dr Altinakar were admitted as evidence by way of reopening or evidence in reply. Instead, it is to be addressed by identifying what topic Dr Altinakar was permitted to address and, most importantly, why. In Rodriguez (No 18), I treated the application to adduce further evidence as an application to reopen, however I did not and did not need to characterise the evidence being adduced as such. What is significant is that on this topic the plaintiff was only granted leave to address a limited issue because that would enable the unfairness that was occasioned by Seqwater's conduct to be rectified. As explained above, the crucial difference between evidence that was allowed and that which was rejected in Rodriguez (No 18), was that to have permitted the latter would have conferred on the plaintiff leave to revisit a decision it previously made about the expert evidence it would adduce, whereas to permit the former would not. [81] Rodriguez (No 18) made it clear that the same approach would apply to the defendants. [82] To now allow Seqwater and SunWater to adduce expert evidence on the topic of the Lockyer Creek inflows would be granting them leave to revisit deliberate forensic choices they previous made not to adduce evidence on that topic. It follows from Rodriguez (No 18) that, given the late stage of this litigation and the consequences that would flow from allowing the evidence, they should not be permitted to do so.
5. Senior Counsel for Seqwater, Mr O'Donnell QC, submitted that the further reports of Dr Altinakar reveal a relevant change in his opinions that warranted his client being allowed to adduce further expert evidence. He submitted that in his further reports Dr Altinakar has effectively recanted his acceptance that the Aurecon/URBS model is the most reliable source for deriving inflows at the boundary conditions and instead expresses a preference for the rated flow at at least one boundary condition, namely Rifle Range Road. He also submitted that Dr Altinakar had revised his evidence by asserting for the first time that the Aurecon/URBS model does not model the true flows for each location in the model. [83] Mr O'Donnell QC submitted that these "drastic" changes carried with them an entitlement on his part to respond. [84] Mr O'Donnell QC submitted that a failure to allow his client to adduce expert evidence in response would be a breach of natural justice. [85]
6. Mr O'Donnell QC further noted that in his October 2017 report Dr Altinakar stated that receipt of the Aurecon/URBS data led him to conclude that his model "should be modified by including the contributions from several important tributaries and various catchment areas" and he used the "latest hydrological simulation results that were provided in the BRCFS data". [86] Mr O'Donnell QC's submission continued: [87] "So at the time your Honour asked why didn't you, prior to March 2018, deliver, for example, a report by Dr Toombes? We replied on this basis: it was unnecessary. Dr Altinakar is accepting the reliability of the model flows from the Aurecon model, including for Lockyer Creek. He's not there saying, "I've looked at the Aurecon model flows at Rifle Range Road and I don't think they're reliable. I think the rate of flows would be the true representation," as he is now saying. He was accepting that the Aurecon model flows, including for Lockyer Creek, should be used, and therefore, it was unnecessary for us to deliver a report saying that the model flows were preferable to the rate of flows at Rifle Range Road. It was enough for us to say in cross-examination, "You accept the Aurecon model flows are more reliable than the rated flows," which he did, "but you didn't use them," and he accepted that. And he put the lack of use down to the difficulty he had in getting the information out of the Aurecon model in printing out this effect or thing. " We say the ballpark position has now changed because for the first time he's coming out and saying, "No, the rate of flows are more reliable than the model flows," not an opinion he had ever previously expressed. That's my submission, thank you."
7. This submission sought to identify some change in opinion on the part of Dr Altinakar between his October 2017 report and oral evidence on 11 April 2018 on the one hand and his October 2018 report on the other and deploy that as a basis for allowing Seqwater to revisit its decision as notified on 1 March 2018 not to rely on evidence in response. I do not accept that. The submission overstates the effect of Dr Altinakar's October 2017 report in that Dr Altinakar also stated in that report that he was using the rated flows at Rifle Range road and otherwise expressed satisfaction that his model overall "achieved good results". [88] There was no relevant change in opinion between Dr Altinakar's October 2017 report and modelling and his redacted 2018 reports. Dr Altinakar expressed satisfaction with the 2017 Set up in both sets of reports.
8. Moreover, Mr O'Donnell QC's submission overlooks the fact that an affidavit of Mr Malone was served only one day prior to Dr Altinakar's evidence. As noted above, the point raised in cross examination of Dr Altinakar was not simply that the Aurecon/URBS model flows were generally preferable to rated flows. The real point that was raised was that the peak inflow rate he used at Rifle Range Road was significantly understated. That was the point sought to be raised for the first time by Mr Malone's affidavit and the cross‑examination. It was the point made by Seqwater in submissions. It should have been raised earlier with Dr Altinakar so he had the proper opportunity to respond
9. Otherwise, the balance of the Mr O'Donnell QC's submissions are directed towards establishing that there has been some change in the evidence given by Dr Altinakar in April 2018 under cross‑examination and his further redacted reports. Assuming, without deciding, that there has been some change in Dr Altinakar's evidence on this point between his oral evidence in April 2018 and his further (redacted) October 2018 report on the topic of the appropriate flows at Rifle Range Road, that is immaterial to whether any basis has been shown for allowing Seqwater to reconcile from its deliberate decision in March 2018 not to adduce expert evidence prior to Dr Altinakar giving oral evidence. The fact that Dr Altinakar has been given a further opportunity to address that topic has only arisen from the circumstance that, contrary to their previous advice, Seqwater did serve and rely on an affidavit in response to Dr Altinakar's report, namely Mr Malone's affidavit which was served the day prior. If Mr Malone's evidence had been served at an appropriate time in advance of Dr Altinakar's evidence then Dr Altinakar would have been able to address it by giving the evidence that he does in his October 2018 report. Had that evidence been given on 11 April 2018 then it would have been no reason to grant leave to Seqwater and SunWater to revisit their decisions not to adduce expert evidence or other evidence in response.
10. At one point in his submissions, Mr O'Donnell QC submitted that if the evidence given by Dr Altinakar in his further (redacted) report had been given in oral evidence in April 2018 then Seqwater could have sought to cross examine a response to that explanation out of one of the flood engineers, Mr Ayre, or Mr Collins, both of whom gave evidence after that time. [89] Apparently, Mr Ayre was involved in the preparation of the Aurecon/URBS modelling. It is difficult to determine in retrospect whether leave to adduce that evidence from Mr Ayre would have been granted. However, I have no doubt that the price of leave being granted would have been the affording to Dr Altinakar of a further opportunity to respond and that would have most likely occurred within the confines of the trial dates available in 2018. As for Mr Collins, as I have stated, the premise of much of Dr Altinakar's October 2018 report is an acceptance of Mr Collins' affirmation of the Aurecon/URBS modelling at O'Reilly's Weir. Given that, and that, consistently with Rodriguez (No 18), he could potentially have given some further evidence but did not, it is sheer speculation to consider that he could have assisted. In the end result, the lost potential for this further evidence to be adduced is a consequence of Seqwater's conduct in incorrectly advising Rodriguez that it did not propose to rely on any evidence in response to Dr Altinakar in the first place.
11. To afford Seqwater leave to tender the report of Dr Toombes, and SunWater leave to tender the report of Dr Markar, would be to allow them to revisit the deliberate decisions they notified in March 2018 not to rely on evidence in response to Dr Altinakar. To take that course would be inconsistent with the reasoning and outcome in Rodriguez (No 18). If that were to occur, then Rodriguez would become entitled to revisit its decisions and that could extend to the undertaking of a remodelling exercise similar to that which produced the 2018 Set up. Not surprisingly the result of that would, at this very late stage of the proceedings, cause further significant delay, substantial costs and use of Court time.
12. Both Seqwater and SunWater were afforded a proper opportunity to respond Dr Altinakar's October 2017 report and modelling. They chose to respond by advising that they would not adduce evidence. It is not a breach of natural justice to hold parties, especially sophisticated litigants, to the forensic decisions they have made when there has not been any relevant change in circumstances.
13. It was for these reasons that I made the orders on 11 March 2019. I further order that costs of the application to tender the reports of Dr Toombes and Dr Markar be reserved.

Endnotes

1. EXP.ROD.016.0115 at [16].
2. EXP.ROD.016.0115 at [277].
3. EXP.ROD.016.0115 at 0458.
4. T 27/11/2017; p 40.11; p 44.40.
5. EXP.QLD.001.1492 at 1498.
6. LAY.SEQ.015.0001.
7. at [10].
8. at [11].
9. T 3442.
10. T 3442.8.
11. T 3443.14.
12. T 3443+.
13. T 3443.35.
14. T 3450.3.
15. T 3454.6.
16. T 3454.8.
17. EXP.QLD.002.0033_2 at [55].
18. T 8558 to 8559.
19. SEQ.012.011.0095.
20. See T 8745 to T 8748.
21. SEQ.012.011.0011.
22. SEQ.012.011.0012.
23. SEQ.012.001.0014.
24. T 3446.28 (Altinakar); T 10238.43 (O'Donnell)
25. SBM.020.004.0001 at [2508] to [2510]
26. EXP.ROD.017.0001; EXP.ROD.019.0001.
27. Rodriguez (No 18) at [45].
28. Rodriguez (No 18) at [2] and [57].
29. Rodriguez (No 18) at [69].
30. Rodriguez (No 18) at [65].
31. Rodriguez (No 18) at [69].
32. Rodriguez (No 18) at [77].
33. Rodriguez (No 18) at [70].
34. Rodriguez (No 18) at [70].
35. Rodriguez (No 18) at [71].
36. Rodriguez (No 18) at [73].
37. EXP.ROD.019.0001_2; EXP.ROD.017.0001_2.
38. EXP.ROD.019.0001_2 at [117]
39. Toombes Report at [74]; T 10219.30 (Owens).
40. EXP.ROD.019.0001_2 at [119].
41. EXP.ROD.019.0001_2 at [122].
42. EXP.ROD.019.0001_2 at [122].
43. See SEQ.093.005.0190 at .0215.
44. EXP.ROD.019.0001_2 at [125].
45. EXP.ROD.019.0001_2 at [128].
46. EXP.ROD.019.0001_2 at [130].
47. EXP.ROD.019.0001_2 at [122].
48. AID.500.027.0001 at .0004.
49. AID.500.027.0001 at .0004.
50. EXP.QLD.002.0033_3 at .0037_3.
51. EXP.QLD.001.1285 at .1295 and MSC.010.384.0001 at .0002.
52. AID.500.023.0001_2 at 0006_2.
53. AID.500.037.0001 at .0004.
54. Toombes Report at [91] to [104].
55. Toombes Report, Executive Summary, page 1.
56. Toombes Report at [59ff].
57. Toombes Report at [75].
58. T 10230.27 to T 10231.18.
59. T 10231.20.
60. T 10226.20 to T 10227.24; T 10229.13 - .33.
61. First Defendant's submissions on plaintiff's objections to the evidence of Dr Toombes at [6].
62. First Defendant's submissions on plaintiff's objections to the evidence of Dr Toombes at [7].
63. Toombes Report at [103].
64. T 10229.35 to T 10230.25.
65. Toombes Report at [109].
66. T 10221.25 to T 10226.17.
67. EXP.SUN.011.0001 at [51] and [54]; T 10222.15 (Owens).
68. EXP.SUN.011.0001 at [13] and [21] to [26].
69. EXP.SUN.011.0001 at [44].
70. EXP.ROD.016.0561 at .0739.
71. T 10223.8 to T 10229.11.
72. EXP.SUN.011.0001 at [48]; T 10222.40 (Owens).
73. EXP.SUN.011.0001 at [61].
74. See Plaintiff's submissions on objections to reports of Dr Toombes and Dr Markar at 1 to 1.
75. See Plaintiff's submissions on objections to reports of Dr Toombes and Dr Markar at 1.
76. T 10275.39.
77. T 10275.41 to T 10276.23 (Owens).
78. Or a permutation of the modelling that allowed for any corrected hydrograph: see [15].
79. T 10257.43 to T 10258.43 (Williams); SBM.030.010.0001 at [2] to [3].
80. T 10258.42 (Williams).
81. Rodriguez (No 18) at [65], [69] and [71].
82. Rodriguez (No 18) at [65], [66] and [73].
83. Seqwater's submissions on plaintiff's objections to the evidence of Dr Toombes at [26].
84. Seqwater's submissions on plaintiff's objections to the evidence of Dr Toombes at [26] to [28].
85. T 10237.42.
86. EXP.ROD.016.0561_OBJ at 0739; T 10256.44 (O'Donnell).
87. T 10257.2.
88. EXP.ROD.016.0115 at .0120, [18].
89. T 10237.22 - .32 (O'Donnell). 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: 14 March 2019