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

Background

1. During 2016, the plaintiff served the first round of reports and modelling undertaken by Dr Altinakar. Dr Altinakar's evidence addressed a discrete aspect of the plaintiff's case on causation, namely, whether the defendants' alleged negligence in operating Wivenhoe and Somerset Dams in the immediate period up to 11 January 2011 was causative of flooding at the plaintiff's property (and those of certain sample group members). To that end, Dr Altinakar used his modelling system known as DSS-Wise to construct a two-dimensional mathematical model of the Greater Brisbane Area which was meant to replicate the flow of water during the flood event in early January 2011 and enable modelling of what would have been the flooding in areas of size 10m x 10m had different outflows from Wivenhoe Dam occurred that corresponded with what the plaintiff contended were non-negligent dam operations.
2. In response to the material from Dr Altinakar, the first defendant, Queensland Bulk Water Supply Authority t/as Seqwater ("Seqwater") served reports from a Mr Babister. The third defendant, the State of Queensland (the "State"), served reports from a Mr Collins. In his report dated May 2017, Mr Collins noted that the results of the Brisbane River Catchment Flood Study ("BRCFS") had just been released. [3] He expressed the opinion that Dr Altinakar had "significantly underestimated the flow contribution from Lockyer Creek". [4]
3. In August 2017, I allowed an application by the plaintiff for leave to amend its Statement of Claim and leave to rely on further reports from the plaintiff's dam operations expert, Dr Christensen, containing ten alternative simulations for the conduct of flood operations (Rodriguez & Sons Pty Ltd v Queensland Bulk Water Supply Authority trading as Seqwater (No 9) [2017] NSWSC 1116). This meant that the plaintiff had to provide updated modelling of the flooding consequent on using those scenarios from Dr Altinakar. The modelling of each such scenario can take a number of days (see Rodriguez & Sons Pty Ltd v Queensland Bulk Water Supply Authority t/as Seqwater (No 3) [2015] NSWSC 838 at [43] to [47]).
4. 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.
5. 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. [5] He said he used the "the latest hydrologic simulation results that were provided in the BRCFS Data using the 'Aurecon URBS model'". [6] 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". [7]
6. The plaintiff paid a heavy price for the success of the amendment application. The granting of the application necessitated a postponement of the trial for a number of months until December 2017. The plaintiff was ordered to pay the costs thrown away by the amendment and the adjournment. The plaintiff was also placed at a tactical disadvantage because, when the hearing commenced in December 2017, the plaintiff had only just received the defendants' evidence responsive to Dr Christensen's simulations and had not received any material responding to Dr Altinakar's revised reports. One of the reports it had just received was a report from an engineer with expertise in hydraulic and hydrological modelling, Mr Andrew Ickert. In his report, Mr Ickert queried the approach taken by Dr Christensen to dam operations when the level of Wivenhoe Dam exceeded EL 74.0m AHD and referred to an alternate method of operating the dam when the water level reached that point (the "Ickert Variation"). [8]
7. 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 [9] whereas the State suggested it should be able to serve its material during December 2018.
8. 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.
9. 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". [10]
10. 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".
11. 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".
12. On 14 March 2018, SunWater advised that it did not intended to serve any evidence in response to Dr Altinakar.
13. 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. [11] 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.
14. 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. [12] His affidavit then states: [13] "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)."
15. Mr Malone then set out a hydrograph showing the difference between the rated and calculated flows at this point.
16. 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. [14] 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. [15] 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"). [16]
17. Dr Altinakar was cross‑examined on Mr Malone's affidavit for some time. [17] Dr Altinakar stated that he had only received it the day before he gave evidence. [18] 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. [19] The cross‑examiner then suggested to Dr Altinakar that a difference in peak flow of 761m3/s could not be dismissed as immaterial. [20] 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". [21]
18. 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.
19. 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.
20. 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". [22] 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).
21. 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. [23]
22. 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. [24]
23. 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.
24. 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.
25. 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."
26. Mr Collins was cross‑examined on 8 August 2018. Perhaps unwisely, the cross‑examination tested his assertions about materiality. [25] 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.
27. 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. [26] 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. [27] This was an unfortunate response especially when considered in the context of the earlier email sent on 1 March 2018.
28. 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. [28] 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.

Dr Altinakar's Revised Reports

1. Revised Report 1 and Revised Report 2 address four matters.
2. First, Revised Report 1 documents the recalibration of Dr Altinakar's 2017 model (the "2017 Setup") of the Actual Scenario of the flood ("Actual 2017 Scenario") using the inflow discharge figures for Lockyer Creek immediately upstream of the Rifle Range Road Alert [29] and a revised inflow discharge hydrograph for the Bremer River to be imposed at boundary location (BND05) derived from the BRCFS. This process did not just involve re‑running the 2017 Setup and substituting two different inflow figures. Instead, it was an iterative process of calibration that involved varying the so‑called Manning Roughness coefficients of water channels across the 2017 Setup. This resulted in the production of a configuration of the model represented by a set of Manning's coefficients (the "2018 Setup") which when applied to the actual discharges from the rivers and Wivenhoe Dam seeks to model the actual flood (described as the "Alternative Actual Scenario Simulation"). In addition, the model was reconfigured so as to break down the Brisbane River channel from two sections into sixteen sections which each could then have separate Manning's coefficients applied to them to achieve greater granularity. [30]
3. Second, Revised Report 2 applied the 2018 Setup to Dr Christensen's ten counterfactual simulations of flood operations and five Ickert Variations in order to ascertain whether those simulations would have inundated the plaintiff's property and the property of sample group members.
4. Third, Revised Report 2 applied the 2017 Setup to five Dr Christensen's simulations that had the Ickert Variation applied to them. [31]
5. Fourth, in Revised Report 2 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. He concluded that the 2017 Setup and Actual 2017 Scenario are a better representation of the 2011 flood event. [32]
6. Three further points should be noted about Revised Report 1 and Revised Report 2.
7. First, it must be remembered that what is currently in evidence is not just the reports of Dr Altinakar that were tendered when he gave evidence in April 2018, but a model of the flood event and the topography of the Greater Brisbane Area represented by the 2017 Setup. Thus, the third matter noted above, that is the output of the 2017 Setup when applied to an Ickert Variation on five of Dr Christensen's scenarios, in substance represents no more than a textual description of the mathematical output of a model that is in evidence. No calibration or further exercise in judgment was applied by Dr Altinakar to produce those outputs.
8. Second, one matter that was introduced in Revised Report 1 and Revised Report 2 were cross‑sectional diagrams for the affected properties of all of the sample group members. These were not produced in Dr Altinakar's earlier reports save for the plaintiff's property. However, as with the Ickert Variations, these are not the product of any further exercise in judgment or calibration by Dr Altinakar. Instead, they simply represent printouts of material that is contained within the already tendered model.
9. Third, on this application Seqwater read an affidavit from one of its solicitors, Ms Kione Johnson, sworn 20 November 2018. [33] Ms Johnson states that she reviewed the revised reports of Dr Altinakar with the assistance of a technical advisor to her firm. She asserts that Dr Altinakar's reports include new evidence that she contends does not arise from just the use of the different flows. Most of that has already been described. The aspects that have not include the use by Dr Altinakar of an outflow from the BRCFS as a comparator to calibrate the flows under his Alternative Actual Scenario Simulation at Moggill, an apparent use of a different number of flood marks for calibration of the 2018 Setup compared to the 2017 Setup and what appears to be an unexplained different set of cross‑sectional points for the plaintiff's property used in describing the output of the Alternative Actual Scenario Simulation compared to the scenarios produced by the 2017 Setup. [34]

Affidavits Read on the Application

1. The plaintiff read an affidavit of the partner with carriage of the matter, Ms Gilsenan, sworn 10 October 2018. Ms Gilsenan's affidavit sets out some of the history of the application, most of which is described above. Her affidavit also outlines the work undertaken to retain Dr Altinakar to produce the revised reports between 2 August 2018 and October 2018. Based on that affidavit, I am satisfied that Dr Altinakar's revised reports were produced with appropriate diligence in that period.
2. The State read an affidavit from one its solicitors, Christopher Gasteen sworn 19 November 2018. [35] Mr Gasteen stated that two of its expert witnesses, Mr Collins and Mr Giles, reviewed Revised Report 1 and Revised Report 2. He sets out some preliminary problems they had identified with Dr Altinakar's 2018 Setup and Alternative Actual Scenario Simulation. [36] He states that, if the application is allowed, then the State will seek to adduce additional evidence which he anticipates will come from those two witnesses. He expects that it would take a further four weeks to provide that material.
3. As noted, Seqwater read an affidavit from Ms Johnson. Ms Johnson described the prejudice occasioned to Seqwater from the delay in the commencement of the trial and then the events between the time that Dr Altinakar gave evidence and receipt of the revised reports in October 2018 noted above. Given the time of year, Ms Johnson estimates that it will take a further 14 to 16 weeks for Mr Babister to prepare reports in response to Dr Altinakar's revised reports, another one month for the legal team to review the report and three weeks for Senior Counsel and the solicitors to prepare to cross‑examine Dr Altinakar and prepare Mr Babister for cross‑examination. [37] She estimates that a resumed hearing will occupy two weeks of hearing time. [38] She states that she "estimate[s] the timeframe to consider, respond and prepare for cross‑examination in relation to the 2018 reports could take up to 6 months given the summer vacation and subject to the availability of key personnel". [39] Ms Johnson estimates the costs involved as at least $400,000 including costs and disbursement. [40] The reference to the availability of key personnel is to her and the technical adviser's absence on leave and the relevant Senior Counsel's engagement in a trial from March 2019 until July 2019. [41]
4. Ms Johnson did not outline the course of events that led to Seqwater advising the plaintiff on 1 March 2018 that no affidavit evidence in response to Dr Altinakar would be relied on and then the subsequent service of an affidavit doing exactly that on the day before Dr Altinakar gave evidence. In particular, she did not address when Mr Malone was asked to consider Dr Altinakar's 2017 reports, when he produced the hydrograph noted above and why his affidavit was not filed earlier.

Findings

1. I am satisfied 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. This arose from the combination of the service of Mr Collins' report dated 21 December 2017 and Seqwater's email of 1 March 2018. From that time, the position taken by the plaintiff was that any debate over these figures went nowhere in the absence of responsive evidence which suggested that the differences were material. Some evidence to that effect was received when Mr Collins' revised statement was served in late April 2018 which, to an extent, was expanded upon in his oral evidence.
2. It is clear that the plaintiff revised its view on proving the immateriality of the differences in boundary flows in early August 2018 most likely because of a perception that the Court was concerned about the issue and perhaps because of the answers given by Mr Collins in oral evidence. Thereafter, I am also satisfied that between 2 August 2018 and mid‑October 2018 the plaintiff undertook all reasonable efforts to obtain Revised Report 1 and Revised Report 2.

Substantive Submissions

1. Since October 2018, the parties have exchanged substantive written submissions on all issues in the trial. Some aspects of those submissions are relevant to this topic. Thus, the plaintiff's written submissions described Mr Malone's affidavit as a "surprise affidavit" and Seqwater's tactics as "cynical and trial by ambush". [42]
2. In response, Seqwater's submissions attacked the reliability of Dr Altinakar's modelling on the basis, inter alia, of the inflow figures at these boundary points. [43] It's submissions also responded to the allegation that they acted "cynic[ally]" and conducted a "trial by ambush" with indignation. [44] These submissions sought to characterise Mr Malone's affidavit as "merely a convenient presentation of information". [45] Seqwater's submissions contend as follows in relation to the allegation of misrepresentation arising out of the email dated 1 March 2018: [46] "Next, we turn to the accusation of misrepresentation. This too should be rejected. As to this: (a) The plaintiff is attempting to contort a statement that Seqwater would not be serving a further report from Mr Babister, or calling Mr Babister, so as to make it apply to Mr Malone's innocuous affidavit. (b) The service of Mr Malone's affidavit is not inconsistent with the statement. As we have observed, that affidavit was (relevantly) no more than a convenient presentation of information in the source material used by Prof Altinakar. It was not in the nature of a responsive report of the kind covered by the statement. (c) Finally, timing is relevant here too. At the time the statement was made, the practical difficulty in actually presenting in Court the precise electronic information from within the mass of Prof Altinakar's electronic source data had not been appreciated. Such practical difficulties are often confronted close to the time of the cross-examination. That is what occurred here. It was not a case of deliberate delay, cynical conduct or trial by ambush. Rather, it was an attempt to present that information in the transparent way described above."
3. In relation to (a), the email of 1 March 2018 was not a statement that Seqwater "would not be serving a further report from Mr Babister". The email relevantly stated that "Seqwater does not intend to serve any evidence in response to Dr Altinakar". As I have stated, Mr Malone's affidavit was material responding to Dr Altinakar's revised reports.
4. In relation to (b), the affidavit was "more than a convenient presentation of information in the source material used by Prof Altinakar". It contained information that Dr Altinakar could not extract, but Mr Malone could, given his expertise and familiarity with the material. If it had been tendered without an explanatory affidavit it would have gone nowhere.
5. In relation to (c), I suspect that this represents the true position but it is devoid of evidentiary support. As noted in her affidavit, Ms Johnson declined to address the course of events that led to the filing of Mr Malone's affidavit.

Submissions on the Application

1. In its written submissions in support of the application, the plaintiff recited the above background. It contended that Mr Collins' evidence was not sufficient to raise any real issue about the significance or materiality of the differences in inflows identified by Mr Malone and concerning the Bremer River. Nevertheless, the plaintiff stated that that it apprehended that the defendants would submit that they are material. Thus, the plaintiff contended that, if the application was refused, the plaintiff will have been denied an effective opportunity to respond to any such submission. [47] The plaintiff also contended that a consideration of the nature of the evidence, the absence of an effective opportunity on the part of the plaintiff to adduce it, and the fact that this is a representative proceeding affecting the interests of thousands of group members, warranted the application being granted. The plaintiff contended that, given the approach previously adopted by the defendants to Dr Altinakar's evidence, little further evidence would be adduced if the application was granted and any further hearing could be "accommodated in the new Court term". [48] In oral submissions, Senior Counsel for the plaintiff, Mr Owens SC, submitted that the scope of any further hearing concerning the subject matter of Revised Report 1 and Revised Report 2 could be further reduced by ordering a conclave of the relevant experts.
2. Seqwater opposed the application to reopen. In its written submissions it contended that the application was governed by both Uniform Civil Procedure Rule 31.28, such that exceptional circumstances were required before the reports could be adduced, and by the principles apposite to an application to reopen. [49] It further submitted that to refuse the application would not occasion significant prejudice to the plaintiff given the plaintiff's contention that there is no or little substantive evidence suggesting the differences in inflows was material. [50] Seqwater also submitted that there was a deliberate decision on the part of Dr Altinakar prior to his giving evidence not to utilise these inflows, [51] a proposition I reject in light of Dr Altinakar's evidence that he could not properly access the relevant data. Otherwise, by reference to the evidence of Ms Johnson, Seqwater's written submissions contended that, if the application was granted, it would be prejudiced and the interests of finality in litigation would be undermined. [52] The State's written submissions were to similar effect although the submissions on prejudice and the consequences for the litigation referred to Mr Gasteen's affidavit.
3. In its brief written submissions, SunWater noted that it opposed the plaintiff's application. SunWater noted that if the application was granted it would not seek to adduce any evidence in response but would seek to further cross‑examine Dr Altinakar. At this point, I note that SunWater played no role in the chronology of events that unfolded. The inconvenience to it of having to attend to cross‑examine Dr Altinakar is a relevant form of prejudice that I must consider in determining the application.
4. One matter emphasised in the oral submissions of Senior Counsel for Seqwater, Mr Pomeranke QC, was that Dr Altinakar's reports went well beyond a mere correction of the 2017 Setup by the inclusion of different inflow figures. He referred to the various features described above which he contended rendered it a different modelling exercise. [53] Senior Counsel for SunWater, Mr Williams SC, contended that the scope of any further hearing would be wider than previously because the defendants could legitimately explore the differences between the 2017 Setup and 2018 Setup and the results they produce. [54]

Principles

1. As noted, Seqwater's written submissions contended that it was incumbent on the plaintiff to show "exceptional circumstances" under Uniform Civil Procedure Rule 31.28(4)(a) to adduce further expert evidence in the form of Dr Altinakar's reports because they were neither served in accordance with UCPR 31.28(1) and otherwise did not "merely update an earlier version of a report that has been served" (cf UCPR 31.28(4)(b)). I do not accept this submission. Uniform Civil Procedure Rule 31.28 is directed to the timing of the service of expert reports. As a matter of substance, both of Revised Report 1 and Revised Report 2 were served more than 28 days prior to the date of any hearing at which leave may be granted to use them (UCPR 31.28(1)(c)). Further, in relation to the report dated 22 October 2018, that report was served pursuant to an order made by the Court on 11 October 2018 (UCPR 31.28(1)(a)).
2. Instead, the application is governed by the principles applicable to an application to reopen informed by s 56 and s 57 of the Civil Procedure Act 2005 (NSW) ("CPA") (s 58(2)(a)). Thus, the overriding principle is what the interests of justice require (Urban Transport Authority of NSW v Nweiser (1992) 28 NSWLR 471 at 478; "Nweiser"). The various factors affecting an assessment of the interests of justice include the following.
3. First, the nature and significance of the evidence sought to be adduced (Nweiser at 477; ASIC v Rich [2006] NSWSC 826 at [18(e), (h) and (i)]).
4. Second, the timing of the application in the context of the litigation as a whole (The Movie Network Channels Pty Ltd v Optus Vision Pty Ltd [2009] NSWSC 132 at [4]).
5. Third, the circumstances surrounding the failure to adduce the evidence at an earlier stage in the proceedings (CPA; s 58(2)(b)(iv) ASIC v Rich at [16] and [18((b),(d) and (i)]) including any delay in making the application (CPA; s 56(2)(b)(ii) and (iii)). In particular, if there was a deliberate decision made not to call the evidence then "ordinarily that will tell decisively against the application" (Smith v New South Wales Bar Association (1992) 176 CLR 256 at 266-7). On the other hand, if the necessity to call the evidence could not have been reasonably foreseen then that will favour the application (Nweiser at 479 to 480) although if the evidence was not called through mistake or inadvertence then "the justice of the case may well point to the granting of the application" (Nweiser at 476). Any failure or compliance by a party with its under obligations under s 56(3) of the CPA bears upon the exercise of the power to reopen (CPA; s 58(2)(iv)).
6. Fourth, the degree of injustice or prejudice to the party resisting the tender both in terms of the decisions they have made in the course of the litigation to that point, and the additional cost, expense and inconvenience occasioned to that other party (CPA s 56(2)(b)(vi); ASIC v Rich at [18(g)]; and generally, Aon Risk Services Australia Ltd v ANU (2009) 239 CLR 175; [2009] HCA 27; "Aon").
7. Fifth, the public interest in the timely resolution of proceedings including the impact on other litigants of delays in the resolution of these proceedings (CPA s 58(2)(a) and s 57; Aon; ASIC v Rich at [18(h)]).

Decision

1. The significance of the various factors affecting a decision whether to permit a reopening by the plaintiff differs according to the material being considered. In particular, it is necessary to differentiate between so much of the application as concerns the results of the recalibration of the modelling by Dr Altinakar to account for the revised inflow figures on the one hand, and his explanation for why, on reflection, he considers that the inflow figures utilised in the 2017 Setup and the Actual 2017 Scenario are to be preferred to the 2018 Setup and the Alternative Actual Scenario Simulation on the other.

2018 Setup

1. It is difficult to assess the nature and significance of so much of Revised Report 1 and Revised Report 2 as concerns the 2018 Setup (and the Alternative Actual Scenario Simulation). The proceedings are complex, many permutations abound and the parties' positions were nuanced. Thus, the plaintiff submitted that it was strictly not necessary for it to adduce the 2018 Setup because none of the defendants' evidence or submissions truly raised any reason to suggest any difference of opinion over the inflows was material, but as the defendants contend otherwise, the tender was being pursued. The defendants' position mirrored that contention. All that can be stated at this stage is that in light of the defendants' submissions this material has the potential to be of significance to an acceptance of the plaintiff's case on causation.
2. Even allowing for the fact that the plaintiff was incorrectly advised on 1 March 2018 that no evidence in response to Dr Altinakar would be served, I am satisfied that the course of events from 26 April 2018 to early August 2018 reveals that it made a deliberate decision that it would not seek to prove the immateriality of any alteration of the inflows at the boundaries on the Lockyer River to reflect the figures nominated in Mr Malone's affidavit as well as the inflow figure on the Bremer River that was suggested to Dr Altinakar in cross‑examination. It did so even though it had received a (relatively bare) statement from Mr Collins asserting they were material. The plaintiff sought to revisit that issue because of a concern raised by the Court on 1 August 2018. Even if some of the answers given by Mr Collins in his oral evidence on 6 August 2018 affected its deliberations on this topic, that only arose from the questioning of him on behalf of the plaintiff. The attempts by the State to expand the basis for his brief statements as to materiality were rejected. Overall, I am satisfied that careful decisions were made by all parties on the topic of materiality prior to the Court raising the issue on 1 August 2018. The fact that the Court queried the issue is not itself sufficient to warrant any party now being allowed to revisit the issue.
3. In considering the potential prejudice that would be occasioned if this aspect of Dr Altinakar's evidence was to be admitted, it must be remembered that if the plaintiff is to be allowed to revisit its decision not to prove (or further prove) the immateriality of the inflow differences then all the defendants must be allowed the opportunity to revisit their decisions to either not prove (or only just prove) its materiality. Thus, there is a real potential for this to consume much more hearing time than Dr Altinakar's first attendance in the witness box, especially when the additional changes to the 2017 Setup noted above are considered.
4. That said, I am very sceptical of Seqwater's assertions as to the likely period of time, cost and expense that would be involved in its preparation of a response and the estimate that two weeks of hearing time would be required to further litigate the matter. While I accept that Ms Johnson's estimates represent her opinion, I do not accept that her estimates represent a reasonable estimate of the time necessary to respond to Dr Altinakar's revised reports even allowing for the unavailability of key personnel.
5. Instead, I consider that Mr Gasteen's affidavit provides a more realistic assessment of the likely time and expense that would be involved in testing this aspect of Dr Altinakar's evidence, although there should be some additional allowance made for the potential for the defendants to explore the differences between the 2017 Setup and 2018 Setup. I expect that a number of hearing days could be involved in testing this aspect of Dr Altinakar's evidence, and calling evidence in response, with a further hearing date not likely to occur earlier than the second half of March 2019. That would represent a significant extra burden for the defendants and be productive of further delay in the completion of the proceedings.
6. In circumstances where all the parties 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, and that to now allow that issue to be litigated could lead to substantially more hearing time and expense, it follows that so much of the application as seeks to tender evidence on that topic must be rejected. This is an example of a circumstance where the concerns raised by the Court at [28] must give way to the interests of finality in inter‑parties litigation.

Explanation for Preferring 2017 Setup

1. I am satisfied that the course of events 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 the calculated figures for the inflow boundary on Rifle Range Road. If 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. Put another way, in light of the service of Mr Collins' report dated 21 December 2017 and the email of 1 March 2018, the plaintiff could not have reasonably anticipated that there would be any issue raised with Dr Altinakar's use of tributary inflows.
2. Further, to now 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. In fact, it would be consistent with that decision.
3. I accept that there has been a significant delay in the production of this aspect of Dr Altinakar's revised reports since he gave evidence in April 2018. However, that is mostly explained by it being intertwined with the plaintiff's attempt to adduce evidence on materiality. Further, the difficulties caused by that delay are substantially outweighed by the unfairness occasioned by the timing of the service of Mr Malone's affidavit.
4. None of the parties specifically addressed the prejudice that would be occasioned by a decision to admit only this aspect of Dr Altinaker'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.
5. Accordingly, the application to reopen will be allowed insofar as it concerns that part of Dr Altinakar's reports that addresses whether it was appropriate to use the inflow discharge figures for Lockyer Creek immediately upstream of the Rifle Range Road Alert presented in paragraph 11 of the fourth affidavit of Terence Malone sworn 9 April 2018.

Ickert Variations

1. I accept that the delay in the tender of so much of Revised Report 2 which documents the output of the 2017 Setup when applied to five of Dr Christensen's simulations amended by the Ickert Variation was significant. However, as already noted, this aspect of Report 2 is simply documenting the mathematical output of a model already in evidence when different outflows from Wivenhoe Dam are applied. These outputs are not the product of any further calibration or judgment on the part of Dr Altinakar. While there might be some scope for responsive evidence, I expect that will be minimal and will not add much to any further hearing time in litigating the issue just addressed. Further, given the content of the final submissions, it can be accepted that there is a possibility that findings might be made that correspond with simulations that have the Ickert Variation, although I note that at least one party submits it is outside the pleaded case.
2. Further, save for one specific matter, none of the affidavits or submissions point to any specific prejudice that would be occasioned by the tender of this material. The one matter of exception is that Seqwater contended that it declined to cross examine Mr Ickert "in part because the plaintiff was not proposing to advance a causation case based on Mr Ickert's revised simulations". [55] The scope of the plaintiff's case including its case on causation derives from the pleading. As just noted, there is a contestable issue as to whether it is open on the pleadings for the plaintiff to seek a finding of counterfactual simulation that incorporates the Ickert variation. If it is not, then this issue falls away. If it is, then Seqwater bears the consequences of the forensic decisions it made. In that regard, I note that it was present when it was suggested to Mr Ickert in cross‑examination that, if Dr Christensen's simulations were varied in accordance with Mr Ickert's suggested operations for when Wivenhoe Dam was above EL 74.0m AHD, then a superior flood outcome to that which eventuated would have been achieved. [56]
3. Accordingly, the application to reopen will be allowed insofar as it concerns that part of Dr Altinakar's revised reports that documents the output of his 2017 Setup when applied to five of Dr Christensen's simulations that incorporate the variation to dam operations suggested by Mr Ickert in his report bearing the code EXP.SUN.009.0001. For the sake of clarity this includes the cross‑sections of the sample group members' properties.

Further Conduct

1. The parties will need to confer as to the appropriate directions to give effect to this judgment.
2. I will not address the costs of the application at this point as a determination of that issue could be affected by the Court's substantive findings. Costs will be reserved.
3. Accordingly, the Court orders that: (1) The plaintiff's application to reopen be allowed insofar as it concerns: (a) that part of Dr Altinakar's revised reports dated 9 October 2018 and 22 October 2018 that addresses whether it was appropriate to use the inflow discharge figures for Lockyer Creek immediately upstream of the Rifle Range Road Alert presented in paragraph 11 of the fourth affidavit of Terence Malone sworn 9 April 2018; (b) that part of Dr Altinakar's revised reports dated 9 October 2018 and 22 October 2018 that documents the output of his 2017 Setup when applied to five of Dr Christensen's simulations that incorporate the variation to dam operations suggested by Andrew Ickert in his report bearing the code EXP.SUN.009.0001; (2) The plaintiff's application to reopen be otherwise dismissed; (3) The parties confer as to the appropriate directions to give effect to this judgment. (4) Costs of the application be reserved.

Endnotes

1. EXP.ROD.017.0001.
2. EXP.ROD.019.0001.
3. EXP.QLD.001.1285 at 1288.
4. EXP.QLD.001.1285 at 1291.
5. EXP.ROD.016.0115 at [16].
6. EXP.ROD.016.0115 at [277].
7. EXP.ROD.016.0115 at 0458.
8. See for example, EXP.SUN.009.0001 at 0232.
9. T 27/11/2017; p 40.11; p 44.40.
10. EXP.QLD.001.1492 at 1498.
11. LAY.SEQ.015.0001.
12. at [10].
13. at [11].
14. T 3442.
15. T 3442.8.
16. T 3443.14.
17. T 3443+.
18. T 3443.35.
19. T 3450.3.
20. T 3454.6.
21. T 3454.8.
22. EXP.QLD.002.0033_2 at [55].
23. T 8558 to 8559.
24. SEQ.012.011.0095.
25. see T 8745 to 8748.
26. SEQ.012.011.0011.
27. SEQ.012.011.0012.
28. SEQ.012.001.0014.
29. Report 2 at [114].
30. EXP.ROD.017.0001 at 0004, [2(3)].
31. Revised Report 2, chapter 3, p 61 to 96 and 109 to 111.
32. Revised Report 2 at pp 99 to 107 esp at [130].
33. CRT.020.003.0001; "Johnson Affidavit" at [48].
34. Johnson affidavit at [48ff].
35. CRT.040.002.0001; "Gasteen affidavit".
36. Gasteen affidavit at [9].
37. Johnson affidavit at [58].
38. Johnson affidavit at [58(e)].
39. Johnson affidavit at [59].
40. Johnson affidavit at [60].
41. Johnson affidavit at [61].
42. Plaintiff's written submissions at [2063] to [2064].
43. Seqwater written submissions at [2503] to [2516].
44. at [2517] to [2527].
45. Seqwater written submissions at [2522].
46. Seqwater written submissions at [2525].
47. Plaintiff's outline of submissions concerning Admission of Further Evidence from Professor Altinakar, "Plaintiff's submissions", at [13] to [14].
48. plaintiff's submissions at [40].
49. Submissions of Seqwater Regarding Further Evidence of Dr Altinakar, "Seqwater Submissions" at [5] to [20].
50. Seqwater Submissions at [21ff].
51. Seqwater submissions at [27ff].
52. Seqwater submissions at [39] to [54].
53. T 9236.39.
54. T 9259.23.
55. Seqwater's submissions at [47(d)].
56. see T 8345 to T 8346. 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: 30 November 2018