BEFORE THE CHRISTCHURCH REPLACEMENT DISTRICT PLAN INDEPENDENT HEARINGS PANEL

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1 BEFORE THE CHRISTCHURCH REPLACEMENT DISTRICT PLAN INDEPENDENT HEARINGS PANEL IN THE MATTER of the Resource Management Act 1991 and the Canterbury Earthquake (Christchurch Replacement District Plan) Order 2014 AND IN THE MATTER of the hearing regarding the Natural and Cultural Heritage Proposal of Stage 3 of the Proposed Christchurch Replacement District Plan STATEMENT OF EVIDENCE OF WINSTON DAVID CURRINGTON CLARK ON BEHALF OF THE CHURCH PROPERTY TRUSTEES, THE ROMAN CATHOLIC BISHOP OF THE DIOCESE OF CHRISTCHURCH AND ALPINE PRESBYTERY (SUBMISSION 3670) 14 DECEMBER 2015 WYNN WILLIAMS LAWYERS CHRISTCHURCH Instructing Solicitor: J W A Johnson (jeremy.johnson@wynnwilliams.co.nz) The Church Property Trustees' Solicitor Level 5, Wynn Williams House 47 Hereford Street, P O Box 4341, CHRISTCHURCH Tel Fax

2 1 Qualifications and experience 1.1 My full name is Winston David Currington Clark. I hold the position of Principal in my own structural engineering consultancy practice. I have been in this position since September My qualifications are: BE(Civil), CPEng, IntPE(NZ) 1.3 I am a Fellow of the Institution of Professional Engineers New Zealand (IPENZ) and of the New Zealand Society for Earthquake Engineering Inc. (NZSEE), and a Life Member of the New Zealand Society for Earthquake Engineering Inc. 1.4 I am a member of Association of Consulting Engineers New Zealand (ACENZ), the New Zealand Timber Design Society (NZTDS) and the New Zealand Geotechnical Society (NZGS). 1.5 I have over 45 years experience in the New Zealand design and construction industry. My initial experience was with the Ministry of Works and Development (MWD) in their Head Office then the Wellington District office Structural Design. My final position with MWD was Wellington District Structural Engineer. In 1986 I joined Morrison Cooper Consulting engineers, Wellington, as a Senior Structural Engineer. Through various mergers the consultancy became Sinclair Knight Merz (SKM). In 2007 I retired from the position of Senior Consultant and shareholder, to form my own structural engineering consultancy practice. 1.6 Over my engineering career I have been involved in the detailed design, design management and construction monitoring of a wide range of building and industrial structures in reinforced concrete, structural steel and timber. I am knowledgeable of construction techniques, traditional and modern materials, and current building code requirements, particularly with respect to earthquake resistance. I have an extensive background in the structural strengthening of buildings included buildings with historic significance. This has led to many engagements for the inspection and reporting on the probable earthquake resistant performance of existing buildings and general seismic risk assessment. 1.7 Since the September 2010 Darfield Earthquake I have been engaged by the New Zealand Historic Places Trust to provide structural engineering support to the heritage staff in their Christchurch office. This involvement is continuing.

3 2 Code of conduct 2.1 I confirm that I have read the code of conduct for expert witnesses as contained in the Environment Court's Practice Note I have complied with the practice note when preparing my written statement of evidence, and will do so when I give oral evidence before the Court. 2.2 Unless I state otherwise, this evidence is within my sphere of expertise and I have not omitted to consider material facts known to me that might alter or detract from the opinions that I express. 3 Scope of evidence 3.1 I have been asked to provide evidence from an engineering context on behalf of three church organisations, these being Church Property Trustees (the Anglican Diocese Church), the Catholic Bishop of Christchurch, and Alpine Presbytery. 3.2 My evidence focuses on additional works that I consider could be undertaken to heritage items in an earthquake recovery environment as a permitted activity provided that the works are designed and implemented in accordance with best practice heritage management and principles under the supervision of suitably qualified and experienced heritage professionals. 3.3 The specific works and associated rules that my evidence focuses on are as follows: a Rule P1 - Maintenance of a heritage item; b c Rule P2 Repair of a heritage item (including building code upgrades/strengthening); Rule P3 - Heritage and investigative and temporary; and d Proposed Rule P9 - Reconstruction 4 Executive Summary 4.1 My evidence reaches the following conclusions: i. The activity specific standards applicable to Rules P1, P2 and P7, requiring scaffolding to be erected without fixing to a heritage item is potentially un-safe and could be too restrictive in particular cases requiring safe access to carryout necessary works in a recovery environment. If scaffolding is required to be fixed to a heritage item for health and safety reasons then provided it is done in accordance with best practice heritage management and principles under the

4 design and/or supervision of suitably qualified heritage practitioner then the works should be permitted. ii. It is appropriate within a recovery environment from an engineering perspective, that repair works allow for building code upgrades as a permitted activity, provided that it is done in accordance with best practice heritage management and principles under the design and/or supervision of suitably qualified heritage practitioner. iii. As repair works cannot be designed and implemented until the investigation works have been completed, it is appropriate in a recovery environment that investigative works to all heritage buildings be permitted, provided that it is done in accordance with best practice heritage management and principles under the design and/or supervision of suitably qualified heritage practitioner. iv. Reconstruction works could be undertaken to damaged heritage items as a permitted activity provided that such works are undertaken in accordance with best practice heritage management and principles under the design and/or supervision of suitably qualified heritage practitioner 5 Development of the Replacement District Plan 5.1 It is noted that the Replacement District Plan was developed in response to the damaging effects of the Canterbury Earthquake Sequence that generally occurred during 2010 and I understand that the aim is to ensure a streamlined process for the review of the existing Christchurch district plans (the Christchurch City Plan and the Banks Peninsula District Plan) and for the preparation of a comprehensive replacement district plan for the Christchurch district. 5.2 This was an extraordinary period of earthquake activity that caused extensive damage to heritage items in the Canterbury area due to an intensity of ground shaking well in excess of Building Code design requirements. As a result of the Canterbury earthquakes, from an engineering perspective, a number of heritage items within Canterbury require either repairs, strengthening, adaptation, or even in some cases demolition. It is not possible to provide a one size fits all detailed engineering solution that is applicable for every heritage item that requires strengthening, repair, reconstruction etc. My comments on the rules therefore seek to provide some practical insight to ensure that the matters are addressed appropriately through further processes both within and outside the resource consent process, as is appropriate.

5 6 Assessment of Rules 6.1 It is appropriate in a recovery environment, for professional heritage practitioners to explore and/or review a range of solutions for works involving maintenance, repairs (including building code upgrades), heritage investigative works and reconstruction, and identify the most realistic solution to achieve a viable outcome. With this in mind I have reviewed the following permitted activities from an engineering perspective and advised where I consider that additional works could be incorporated without having an overall detrimental impact on the heritage item. Rule Permitted Activities Heritage Items and Heritage Settings (High Significance (Group 1) and Significant (Group 2)). P1 Maintenance of a heritage item 6.2 I consider it appropriate that owners of heritage items be able to carry out regular and on-going maintenance of heritage items as a permitted activity. However, I consider that the proposed Activity Specific Standard requiring temporary scaffolding to be erected without fixing to any heritage item is potentially un-safe and could be too restrictive in particular cases requiring safe access to carryout maintenance. The likely consequential effect is that essential maintenance is not carried out, as owners of heritage items are reluctant to spend additional funds on obtaining resource consent for works that I understand would otherwise be permitted, causing the heritage fabric to deteriorate. By way of example, a particular heritage building has roofing that is of heritage value. To access elements requiring repair, such as ridge flashings, chimneys or towers, access scaffolding would require support by the roof structure of the building and its roofing. 6.3 I consider that where scaffolding is required to be fixed to a heritage item to ensure best practice from a health and safety perspective, that provided a heritage (architect and/or engineer) professional is responsible for determining an appropriate process for fixing the scaffolding to the heritage item, and that professional has recognised knowledge and appropriate experience, then their professional advice could be relied on by the Territorial Authority to achieve an appropriately implemented solution for access and scaffolding support without the need for a resource consent to be submitted. 6.4 My opinion on this matter are also applicable to the Activity Specific Standards relating to scaffolding that are applicable to the repair of heritage items and works within a heritage setting under Rules P2 and P7.

6 P2 Repair to a heritage item 6.5 I understand that in his evidence, Mr Nixon seeks amendments to the definition of repairs to include building code upgrades. I consider it appropriate that the owners of heritage items be able to undertake regular and on-going repair of heritage items as a permitted activity. I also consider, from an engineering perspective in an earthquake recovery context, it is appropriate that repair works allow for building code upgrades provided that the proposed works are designed and supervised by a heritage (architect and/or engineer) professional. I consider that the ability to undertake building code upgrades as part of a repair strategy has the following benefits from an engineering perspective: A holistic approach can be taken with identifying appropriate solutions for both the repair and structural strengthening works. In particular for damaged areas of structures where the repair itself cannot be completed without integral strengthening works forming part of the repair. Where deconstruction is required to carryout a repair, there could be the opportunity to provide a structural strengthening solution that fits into or behind the space provided by the deconstructed elements. This holistic approach is likely to lead to efficiencies in the use of materials, and with time and cost by fitting the structural strengthening work in with the repair. P3 Heritage Investigative and Temporary Works to a Significant (Group 2) Heritage Item 6.6 From an engineering perspective, I consider that it is vital for the identification of appropriate repair and structural strengthening solutions for heritage buildings that investigation works are carried out to determine the engineering characteristics of the building structure and its fabric. These investigation works can range from minor nondestructive testing, to taking samples for laboratory testing. Each project has different characteristics to be identified, and appropriate testing to evaluate these characteristics. 6.7 These investigation activities, as part of the design process, are important for the development of the most effective solution for the building s recovery. Given that repair works cannot be designed and implemented until the investigation works have been completed, I consider it is counter intuitive to provide for repairs as a permitted activity while proposing a controlled activity status for investigative and temporary works to High Significance (Group 1) Heritage items.

7 6.8 In my opinion, the best person to determine the type and extent of investigation and temporary works for any particular repair, structural strengthening or maintenance works on a heritage building is a heritage (architect and/or engineer) professional who is responsible for determining an appropriate process and outcome for the building. Where such a person is available to the project, their professional advice can be relied on by the Territorial Authority to achieve an acceptable solution without the need for the owners of heritage buildings to apply for a resource consent. I therefore consider that heritage investigative and temporary works to Group 1 heritage items should be a permitted activity provided there is appropriate Activity Specific Standard requiring the works are carried out by, or under the supervision of, suitably qualified and experienced heritage professionals. 6.9 In looking at the Activity Specific Standards for investigative works, the first standard requires the removed heritage fabric to be limited to the the amount immediately necessary to carry out the associated works. I understand that from a planning perspective there are concerns about the reference to the term immediately 1, which Mr Nixon comments on in his evidence. From an engineering perspective, when assessing the requirements for works to a heritage building, including repair and structural strengthening, it is important to consider the building as a whole; not necessarily just the section of the building that is damaged. The designer of the repair or strengthening solution must consider the effect of the repair or strengthening on the possible long-term performance of the building, and that nothing is done that has the potential to cause further harm to the fabric of the heritage building. I therefore support the Submitters request for the removal of the term immediately from the Activity Specific Standards. Proposed new rule P9 - Reconstruction 6.10 Owing to the extent of earthquake damages sustained by numerous heritage items, I consider from an engineering perspective that reconstruction works could be undertaken to damaged heritage items as a permitted activity provided that such works are undertaken in accordance with best practice heritage management and principles under the design and/or supervision of suitably qualified heritage practitioner Where damage has occurred to a heritage item, the repair generally requires a number of tasks, each drawing on different materials and skills. To complete the repair effectively, including reconstruction if required, it is important that all the works are carried out at the same time, or in a logical order, and under the control of one 1 Bob Nixon s evidence Section: P3 - Heritage Investigative and Temporary Works to a Significant (Group 2) Heritage Item

8 heritage professional responsible for the whole job. This is to ensure there is a consistance of approach and that the outcome if fully coordinated with the heritage values of the heritage item. 7 Conclusion 7.1 It is appropriate in a recovery environment, for professional heritage practitioners to explore and/or review a range of solutions for works involving maintenance, repairs (including building code upgrades), heritage investigative works and reconstruction, and identify the most appropriate solution to achieve a viable outcome. Provided that such works are undertaken in accordance with best practice heritage management and principles under the design and/or supervision of suitably qualified heritage practitioner, I consider that from an engineering perspective that these works should be permitted. Winston David Currington Clark 14 December 2015