Christchurch Replacement District Plan
CHAPTER 5:
NATURAL HAZARDS (CLIFF COLLAPSE MANAGEMENT AREAS)
TRANSCRIPT OF PROCEEDINGS
Heard at:Christchurch Plan Independent Hearing Venue
348 Manchester Street, Christchurch
Date:Commenced 25 January 2016
Hearing Panel:Sir John Hansen
Judge John Hassan
Ms Sarah Dawson
Ms Jane Huria
Dr Phil Mitchell
APPEARANCES
DAY 1 – 25 January 2016
<THOMAS RICHARD JUSTICE, sworn...... [9.52 am]
<EXAMINATION BY MR PEDLEY...... [9.52 am]
<CROSS-EXAMINATION BY MR WINCHESTER...... [9.57 am]
<THE WITNESS WITHDREW...... [10.18 am]
<CHARLES IAN WRIGHT, sworn...... [10.28 am]
<EXAMINATION BY MR WINCHESTER...... [10.28 am]
<CROSS-EXAMINATION BY MR PEDLEY...... [10.33 am]
<THE WITNESS WITHDREW...... [10.47 am]
<DR MARK DAVID YETTON, sworn...... [10.47 am]
<EXAMINATION BY MR WINCHESTER...... [10.47 am]
<THE WITNESS WITHDREW...... [11.00 am]
<DR WENDY SUSAN ANNE SAUNDERS, sworn...... [11.04 am]
<EXAMINATION BY MR RANDAL...... [11.04 am]
<CROSS-EXAMINATION BY MR WINCHESTER...... [11.06 am]
<THE WITNESS WITHDREW...... [11.16 am]
EXHIBITS
Page 1
DAY 1 – 25 January 2016
[9.43 am]
SJH: Yes, thank you.
Yes, MrPedley?
MR PEDLEY: Thank you, sir, I have filed some written opening submissions on the matter and no doubt you also received those from the Council and from the Crown.
SJH: Yes.
MR PEDLEY: Hopefully it should be clear from those submissions that there is a very high level of agreement, both between legal counsel and the experts on this issue.
SJH: I suppose the first one, are you contending that this should extend to cliff hazard1 or not?
MR PEDLEY: No, I am not, sir. I am adopting a neutral position on that issue.
JUDGE HASSAN: Well, just on that.
SJH: Well, no, just go through them, you go ahead.
[9.45 am]
JUDGE HASSAN: I just wondered about the scope of your submission.
MR PEDLEY: Certainly, sir, no, that is a fair comment.
JUDGE HASSAN: So in that sense your submission just relates to cliff hazard2, doesn’t it?
MR PEDLEY: Yes, that is fair, sir.
SJH: But the ruling in the appeal actually went further than your submission?
MR PEDLEY: That is probably true as well, sir, yes.
SJH: Which there is no jurisdiction for?
MR PEDLEY: That is fair, sir.
SJH: All right, so we are only concerned with cliffhazard2, that is the main thing we - - -
MR PEDLEY: I am content to proceed on that basis, sir.
SJH: All right, thank you, MrPedley.
MR PEDLEY: Thank you, yes, those two issues where there are areas of disagreement that remain, one is the CCMA1 and the CCMA2 issue and I think we have covered that off already so I will make no further comment on that matter, sir. The other issue is whether occupancy rates should be fixed as part of the certification process and if I may, sir, I will just perhaps offer some brief comments on that before I call - - -
SJH: Could you speak up just a little bit for me?
MR PEDLEY: Certainly. If I just make some brief comments on that issue before I call MrJustice.
So the issue of occupancy rates is raised at paragraph5.6 of DrWright’s evidence where he expresses the view that the occupancy rate should be locked in for the purposes of a certification assessment. And MrJustice takes a different view and considers that occupancy is a factor that should be able to be considered on a site specific basis in order to enable a comprehensive risk assessment to be undertaken.
Taking this back to basics at paragraph12 and 13 of MrJustice’s evidence he describes the fundamentals of geotechnical risk which is defined as the product of the probability of the hazard event occurring and the consequence if that event was to occur. His evidence is that one of the key factors that influences consequence is the occupancy of the land.
In my submission the purpose of providing for a certification regime is to enable a more accurate risk assessment to be undertaken that takes into account the specifics of a particular site and addresses some of the shortcomings of area wide modelling. MrJustice’s view is that in order for such assessment to be properly and comprehensively undertaken both parts of the risk equation, being probability and consequence, should be able to be adjusted as appropriate for that particular site as part of the certification process. This requires the ability to assess occupancy in appropriate circumstances.
Now, this is not to say that there is an open discretion for any expert to assess in any manner he or she sees fit. The process itself would still be tightly controlled by the fact that the assessment must firstly be carried out in accordance with the agreed GNS methodology and, secondly, be subject to independent peer review.
My friend MrWinchester has submitted that such an approach would fall foul of the legal principles regarding certainty and objectivity for a certification regime, however in my submission this is not correct. The Panel has already recognised that the certification process for rock fall hazards inherently involves judgement and associated uncertainty.
However, it was satisfied that adherence to the GNS methodology and the requirement for a peer review sufficiently narrowed the scope of subjectivity or bias in the exercise of that judgement. In my submission the same applies for cliff hazards which is proposed to follow essentially the same certification process as for rock fall hazards but with reference to the applicable GNS reports for cliff hazards.
In my submission it is also important to note that notwithstanding the difference of opinion on this issue it does not seem to translate to any material difference in the plan provisions that the parties have promoted for certification of cliff collapse hazards. All parties agree and accept, with the modifications that have been proposed, the most recent version being attached to the revised rebuttal evidence of DrSaunders. It may therefore be that this matter is an issue that can be better assessed on a site specific basis through the certification process with the inbuilt control of peer review, without something that requires specific amendments to the plan provisions at this stage.
And just one final issue that I will briefly touch on is an amendment illustrated in the revised plan provisions attached to DrSaunders’ evidence, which provides an alternative certification method established by GNS that could potentially be used for cliffs less than 20metres high. And there I am referring to clauseE on pages 12 and 13 of the revised rebuttal. Now, this amendment is principally based on the evidence of DrYetton for the Council.
MrJustice briefly comments on this issue in his rebuttal evidence and states that although he agrees on a technical level with DrYetton he considers that it is not necessary to be more prescriptive in the plan. However, for the same of clarify I can confirm that KI Commercial Limited takes no issue with the changes proposed by DrSaunders provided it remains clear, as it currently is, that this is an alternative optional method and not one which replaces the 2012 GNS report methodology.
That concludes my opening comments, I am happy to answer any questions at this point.
[9.50 am]
SJH: Thank you. Judge?
JUDGE HASSAN: I think I am clear. Just one very quick thing, MrPedley, appendixA to your submissions, as far I can tell, is the same as the version of the policy amendment which is attached to MsSaunders’ evidence?
MR PEDLEY: That is correct, sir.
JUDGE HASSAN: All right.
SJH: DrMitchell?
DR MITCHELL: No, I have no questions, thank you, sir.
SJH: MsHuria?
MS HURIA: No, thank you, sir.
SJH: MsDawson?
MS DAWSON: Just one question, MrPedley, in relation to the occupancy rates and whether it should be fixed or not, you have partly answered my question. So you are not seeking any amendments to the way that the rule references the parameters included in the relevant reports, is it your view that any evaluation of the appropriate occupancy rates at a site specific level can be undertaken in accordance with the parameters already referenced in those reports?
MR PEDLEY: Yes, that is correct, the reference I think in the rule is to the methodology in the GNS reports.
MS DAWSON: And it says “…and the parameters in those reports”?
MR PEDLEY: Yes.
MS DAWSON: So you are happy that wording satisfies whatever flexibility is appropriate for considering occupancy rates?
MR PEDLEY: Yes, that is correct and MrJustice may be able to comment on that further if you wish.
MS DAWSON: All right, thank you.
SJH: All right, thank you, if you would call your witness.
MR PEDLEY: Thank you.
THOMAS RICHARD JUSTICE, sworn[9.52 am]
<EXAMINATION BY MR PEDLEY[9.52 am]
MR PEDLEY: Thank you, if you can please confirm for the Panel that your full name is Thomas Richard Justice?
MR JUSTICE: That is true.
MR PEDLEY: And you have prepared two statements of evidence for this hearing, the first dated 15December 2015 and the second dated 13January 2016, is that correct?
MR JUSTICE: That is correct.
MR PEDLEY: Can you please confirm the evidence is true and correct to the best of your knowledge and belief?
MR JUSTICE: It is.
MR PEDLEY: Thank you. If you can please provide a highlights package of your evidence and remain to answer questions.
MR JUSTICE: Certainly. Good morning. Sir, my evidence is in two parts and I understand it has been pre-read so, as a summary, there is general agreement that certification of cliff collapse areas should be made as a - - -
SJH: Cliff collapse areas, or cliff collapse area2?
MR JUSTICE: Well, at least 2 and 1 is something that perhaps we can discuss, I will allude to that in - - -
SJH: Well, we have just been told it is not part of the hearing in front of us so why do we need to bother with it?
MR JUSTICE: Well, I guess - - -
SJH: Other than you are contending for it in your professional opinion - - -
MR JUSTICE: Yes, well, it comes down to - - -
SJH: - - - it is not an issue for us.
MR JUSTICE: Okay.
SJH: Am I right in that, MrPedley?
MR PEDLEY: Yes, you are right.
SJH: So do we need to have this evidence on cliff collapse1 or not?
MR PEDLEY: No, sir, I don’t believe - - -
SJH: I mean it is for you, you are the one who has got to make the election.
MR PEDLEY: Thank you, sir, yes, I understand that. There was some brief comment on the CCMA1 issue in MrJustice’s evidence - - -
SJH: So you are electing cliff collapse2 only?
MR PEDLEY: Yes, that is correct.
SJH: So just deal with the cliff collapse2, thank you, MrJustice.
MR JUSTICE: Certainly. There is agreement that certification of CCMA2 should occur. We have some technical disagreement in terms of how occupancy should be regarded in any certification process. It is my opinion that some allowance should be made.
Now, the reason for that is that risk, as it is determined at least in the geotechnical profession, is a product of the likelihood of an event occurring multiplied by the consequence should that event occur. And that is a commonly used and very simple form of any risk assessment process, we use that basic methodology for whatever we do and that is the basic methodology at the end of the day and which GNS have used for all the work that they have done to date.
[9.55 am]
So another way of saying that is that where the consequence is greater where we have a greater loss of life, a road for example, where there is a high usage of that road we can generate a high level of risk with a lower likelihood of a particular hazard occurring.
I believe it is my opinion or it is my opinion that that should be reflected in how and what we can do in terms of certification regime. At the moment, well, locking in the parameter at whatever value is deemed appropriate and in my mind at least limits our ability to undertake a site specific assessment where the occupancy is much less. An example I would use would be a property where between the house and the cliff, for example, there is a garden and the garden is really only occupied for a few hours perhaps a day or a week, but certainly nowhere near the occupancy that would be expected in a house.
Similarly a driveway, unless it was an exceptional circumstance, may only have an occupancy of a few minutes in any given day. And I believe if we are doing a site specific certification then there should be an allowance for those kind of occupancy rates to be included in there in the risk assessment process and simply not locked in at 0.67, or 1.0, or 0.9 as has been done in the GNS area wide modelling.
SJH: Thank you. MrWinchester?
<CROSS-EXAMINATION BY MR WINCHESTER[9.57 am]
MR WINCHESTER: Thank you, sir. Good morning, MrJustice. Now, with regard to the assessment of AIFR for cliff collapse areas, what was the occupancy rate based on your understanding of the GNS reports that was adopted for the modelling?
MR JUSTICE: My understanding is that two different numbers were used. 0.9 was used for properties at the top of the cliff and 100 percent or 1 for properties at the bottom.
MR WINCHESTER: Yes, and what is your recommendation then for occupancy rates, is it simply going to be wide open and up to the assessment or opinion of a suitably qualified person, is that what you are suggesting?
MR JUSTICE: No, not entirely. What I am suggesting is and this is in, I am sorry I cannot recall the exact paragraph in my rebuttal statement of evidence, but I can find it. My opinion is that standard rates of occupancy, this is paragraph10 of my rebuttal evidence.
My opinion is that standard occupancy rates can be derived for various scenarios, garden, driveway etcetera, rather than it being an open ended spectrum. In my mind those occupancy rates would be based on a conservative estimate of the likelihood of a particular area being occupied, for example a garden, an avid gardener may be in his or her garden for a few hours, several hours per day every day and that number would be reflected in the standard occupancy rate for that particular area.
MR WINCHESTER: I see. So what you would recommend is that there be recorded somewhere as a point of reference what the occupancy rates to be applied to different areas of land are?
MR JUSTICE: That is correct.
MR WINCHESTER: Right. And where, for example, a dwelling was included within the overlay area are you suggesting you would use different occupancy rates for a dwelling or a fixed one?
MR JUSTICE: Again it would be fixed. Now, I guess the question perhaps in that is also what it would be fixed at and whether that is 0.9 or 1.0 or 0.67.
0.67 is a number that has been used, as I understand, for rock fall so it is slightly lower. But again, it would be an agreed number in that range somewhere between 0.67 to perhaps 1.0 but to be determined?
[10.00 am]
MR WINCHESTER: Yes. And have given any thought to the fact that this is a certification regime which has an important and fixed consequence when considering the input parameters?
MR JUSTICE: I have. I am not sure I understand the question fully.
MR WINCHESTER: So if, for example, a certificate was issued by the Council that means that there is a significant benefit and significant certainty for the recipient of the certificate, do you understand that?
MR JUSTICE: I do.
MR WINCHESTER: Yes, and the Council in issuing that certificate, it needs to be certain because of those consequences.
MR JUSTICE: Sure.
MR WINCHESTER: Yes, and you are satisfied that the exercise of professional judgement in identifying an occupancy rate allows for that certainty and that level of confidence?
MR JUSTICE: Yes I do, and I think the opinion that is expressed by myself and the other expert witnesses is that any certification would be undertaken by a suitably qualified person. That would be a geo professional, and that person would either have a chartered professional engineering status as a geotechnical engineer or a professional engineering geologist, PEngGeol status.
Additionally, there would be a requirement, in my opinion, for any certification to be peer reviewed and I would imagine that that peer reviewer would be a party nominated by Council. So you have a suitably qualified person undertaking the assessment. They are operating under their Code of Ethics to ensure that the subjectivity is as low as it can be and you have a peer review.
MR WINCHESTER: Thank you and have you done any dummy calculations for specific areas of land to see what the difference adopting different occupancy rates would have, in terms of the location of lines?
MR JUSTICE: No I have not. All I can offer perhaps in that space is if we assume the occupancy of a house is set at 1 or 100percent, and taking the example of the garden, the change in value could be as great as 0.25 so, in other words, there is a multiple of four in there reduction in the level of risk.
I have not specifically done, sir, any data calculations but I hope that helps.
MR WINCHESTER: Yes, and where you have got an area of land which is used for a dwelling and gardening and access purposes do I take it under your approach you would adopt the most conservative occupancy rate so to the extent a dwelling was affected you would use the agreed occupancy parameter and that would apply to all of the affected land?
MR JUSTICE: Yes, I think so. Thank you, Mr Justice, thank you, sir.
SJH: Thank you, Judge?
JUDGE HASSAN: Thank you, sir, just on this example just so I can get it clear in my mind about occupancy rates, so you mentioned the garden between the house and the cliff occupied say, a day a week. Is your assumption in that that the person undertaking the work for the purpose of certification, qualified person you mentioned, how would they get a gauge on whether or not there was a garden?
Would it be just their visual gauge?
MR JUSTICE: Yes.
JUDGE HASSAN: And what if there was an application granted before the Council for consent to build a dwelling in the garden area? How does that affect that process?
MR JUSTICE: I think in that case as a building consent would be triggered, it would be my opinion that the certification at that point lapses.
JUDGE HASSAN: Do you know the difference between a building consent and a resource consent?
MR JUSTICE: I do.
JUDGE HASSAN: Well, why did you mention – I am interested in the resource consent you mentioned.
MR JUSTICE: Sorry. Yes, I understand the question.
JUDGE HASSAN: So what would the person undertaking the report do in that situation? There was a garden happily being used, growing vegetables but a resource consent there would enable the construction of a house on the garden. You do not know whether the resource consent is going to be exercised or not.
[10.05 am]
MR JUSTICE: As part of the certification and reporting around that it would be my opinion that wording is provided in that that outlines the assumptions around occupancy and if that were to change then the risk that is calculated becomes null and void.