Mt Eden Main Works Historic Character Delivery Work Plan (Built Heritage Section) CRL-MTE-RME-LKA-PLN-800045
Revision: 001 Date: 29 June 2020
Historic Character Delivery Work Plan (Built Heritage Section)
Historic Character Delivery Work Plan (Built Heritage Section) CRL-MTE-RME-LKA-PLN-800045
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Revision Status Revision
Date
Version details
Prepared By
Approved By
Rev A00
03 April 2020
Draft for Auckland Council and Independent Peer Review
Jane Matthews
-
Rev 000
16 June 2020
Final for pre-lodgement
Jane Matthews
Peter Roan
Rev 001
29 June 2020
Final for submission
Jane Matthews
Peter Roan
Approval Status Name/Title
Signature
Date
Prepared by:
Jane Matthews Heritage Architect
29 June 2020
Approved by:
Peter Roan Link Alliance – Consenting Lead
29 June 2020
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Historic Character Delivery Work Plan (Built Heritage Section)
Table of contents 1. Introduction ............................................................................................. 5 Overview of CRL Works in Mt Eden ................................................................................ 5 HC DWP (Built Heritage Section) Staging ........................................................................ 6 Purpose of the HC DWP (Built Heritage Section) ............................................................. 6 HC DWP (Built Heritage Section) Authors ....................................................................... 7 Relevant Conditions ...................................................................................................... 8 Sustainability .............................................................................................................. 12 HC DWP (Built Heritage) Review and Updates .............................................................. 12
2. Mt Eden Main Works Description .......................................................... 13 Overview of Works ...................................................................................................... 13 Construction Staging and Methodology ....................................................................... 13 Site Description ........................................................................................................... 15
3. Built Heritage Overview ......................................................................... 16 Location of Identified Built Heritage in Proximity to the Mt Eden Main Works .............. 16 Historic Streetscape and Urban Environment Elements ................................................ 20
4. Overview of Potential Effects on Built Heritage During the Mt Eden Main Works .......................................................................................................... 22 Vibration..................................................................................................................... 22 Ground Movement ...................................................................................................... 22 Stormwater Drainage .................................................................................................. 23 Impact Damage ........................................................................................................... 23
5. Management and Mitigation Measures ................................................. 23 Building Condition Surveys .......................................................................................... 23 Pre-Construction Surveys .............................................................................................. 23 Surveys during Construction ......................................................................................... 24 Post Construction Surveys ............................................................................................ 25 Building Record and Salvage Strategy .......................................................................... 25 Historic Streetscape Elements and Walls ..................................................................... 25 Monitoring and Management Measures ...................................................................... 25 Groundwater and Settlement Monitoring .................................................................... 25 Vibration........................................................................................................................ 26 Built Heritage Monitoring ............................................................................................. 26 Managing Maintenance Works to Heritage Buildings during the Construction Works 26 Page 3
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Historic Character Delivery Work Plan (Built Heritage Section) Protection Methodology during Construction Activities ................................................ 26 Rectification Methodology .......................................................................................... 27
6. Heritage Interpretation .......................................................................... 27 7. General Matters..................................................................................... 28 Communication and Consultation ................................................................................ 28 Key Personnel ............................................................................................................. 28
Appendix A: Consultation Record................................................................. 29 A1. CLG Comments ...................................................................................... 29 A2. IPR Comments ....................................................................................... 29 A3. Auckland Council Comments.................................................................. 29 A4. Mana Whenua ....................................................................................... 29 Appendix B: ISCA Requirements................................................................... 30 Appendix C: Staging Drawings...................................................................... 31 Appendix D: Historic Heritage and Special Character Buildings in Proximity to the Mt Eden Main Works ............................................................................. 32
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Historic Character Delivery Work Plan (Built Heritage Section)
1.
Introduction
The City Rail Link (CRL) project comprises the construction, operation and maintenance of a 3.4 km underground passenger railway, running between Britomart Station and the North Auckland Rail Line (NAL) near Mt Eden Station. The CRL also involves the construction of two new underground stations at Aotea and Karangahape and a redeveloped Mt Eden Station (refer to Figure 1-1). The design and construction of the CRL infrastructure between the Aotea and Mt Eden Stations is being delivered by the Link Alliance.
Figure 1-1: CRL Route and Location
This Historic Character Delivery Work Plan (Built Heritage Section) (HC DWP (Built Heritage Section)) has been prepared in relation to the Mt Eden Main Works (“main works”).
Overview of CRL Works in Mt Eden CRL works in the Mt Eden area involve the construction of the southern section of the tunnel structures and the tie-in of the CRL railway to the existing NAL, including the construction of the redeveloped Mt Eden Station. The Mt Eden Active Construction Zone (ACZ) and Construction Support Areas (CSAs) are generally located between Nikau Street to the north, State Highway 1 (SH1) to the east, Dominion Road to the west and the existing NAL to the south. The works in this area include: • • •
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Operational activity required to support the tunnel boring machine (TBM) drive, including control room and plant, storage and spoil handling; Construction of a new Mt Eden Station building, incorporating passenger linkages between the new CRL platform and the modified existing NAL platform; Road over rail bridges at Mt Eden Road, Normanby Road and Ruru Street with sections of road realignment;
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Historic Character Delivery Work Plan (Built Heritage Section) •
• • • •
Grade separation structures for the existing and new rail lines to pass-over and connect with each other, including the Newton Junction Grade Separation Structure, the Eastern Facing Connection and the Western Facing Connection; Construction of a portal vent house building structure; Installation of retaining walls and utilities; Pedestrian and cyclist bridge structures at Fenton Street and Porters Avenue; and New road linkages within the reinstated area post-construction.
Given the nature and scale of CRL construction works in Mt Eden, works are being undertaken in a staged manner, involving: • •
•
Enabling and early works (demolition, network utility relocation and site establishment work) – early works have commenced and will continue to end of 2020; Main construction works (construction of the underground CRL cut and cover tunnels, grade separation structures and trenches, station building and platforms, and tie-ins to the NAL) to be undertaken from mid-2020 through to mid-2023; and Public realm reinstatement – likely to be undertaken from 2021 to early 2024.
HC DWP (Built Heritage Section) Staging To reflect the staged construction approach for the CRL in the Mt Eden area, a series of HC DWPs are being prepared. This HC DWP (Built Heritage Section) addresses the main works, which are detailed in the Construction Environmental Management Plan (CEMP) and summarised in Section 2 of this HC DWP (Built Heritage Section). If required, a HC DWP (Built Heritage Section) will also be prepared for the future public realm reinstatement.
Purpose of the HC DWP (Built Heritage Section) This HC DWP (Built Heritage Section) has been prepared to identify measures that will be implemented to mitigate and manage the potential adverse effects on built heritage during the main works. The objective of the HC DWP (Built Heritage Section) is to avoid, remedy or mitigate adverse effects on built heritage as far as reasonably practicable. The HC DWP (Built Heritage Section) addresses the requirements of CRL designation conditions 41 and 46 and will be implemented throughout the construction period. The HC DWP (Built Heritage Section) forms part of the CEMP for the main works. It has considered buildings located in proximity to the main works which are recognised as having heritage and /or special character value as a result of scheduling in the Auckland Unitary Plan Operative in Part (AUP), inclusion in AUP Special Character Area overlays or listing under the Heritage New Zealand Pouhere Taonga Act 2014. It also addresses the heritage buildings identified in Appendix Two of the designation conditions where relevant. This HC DWP (Built Heritage Section) has been prepared in consultation with the CRL Mana Whenua Forum, Mt Eden Community and Business Liaison Group (CLG), and has been reviewed by the Independent Peer Reviewer (IPR) prior to submission to Auckland Council (as per designation Page 6
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Historic Character Delivery Work Plan (Built Heritage Section) conditions 7 and 11). A record of the consultation and review outcomes, including the Link Alliance’s response to matters raised, is included in Appendix A.
HC DWP (Built Heritage Section) Authors This HC DWP (Built Heritage Section) has been prepared for the Link Alliance by Matthews & Matthews Architects Ltd.
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Historic Character Delivery Work Plan (Built Heritage Section)
Relevant Conditions Table 2-1 outlines the CRL designation conditions relevant to this HC DWP (Built Heritage Section) and where they are addressed in this document. Table 2-1 Designation conditions for HC DWP (Built Heritage Section) and where addressed in this document
Condition No.
Condition
Relevant section of DWP
41.11.141.1
The Historic Character DWP shall be prepared to manage the adverse effects on built heritage and archaeology that may result from associated works prior to, during, and after the construction of the City Rail Link or any part of it.
This document
41.2
The objective of the Built Heritage section is to avoid, remedy or mitigate adverse effects on built heritage as far as reasonably practicable.
This document
To achieve the above objective, the following shall, as a minimum, be included in the built heritage section of the Historic Character DWP: (a) Preparation of a Building Record and Salvage Strategy that outlines a suitable set of procedures for the removal, storage and for later refitting and reuse of elements of heritage buildings and/or structures identified for demolition including the Griffiths Building, Beresford Toilets, Bluestone Toilets, and the rear annex to the building at 223-227 Symonds Street.
N/A
(b) The proposed methods for monitoring building damage that is to be undertaken by a suitably qualified person for the duration of construction works. This includes confirming which Built Heritage buildings and structures are to be subject to a pre and post building condition survey through:
3.0, 4.0, 5.0
(i) Using the updated predicted vibration contours undertaken in Condition 36;
3.0
(ii) Reviewing those buildings in Appendix 2 to these conditions in accordance with Condition 46.1;
3.0 and Appendix D
(iii) Reviewing buildings within the designation footprint (including above sub-strata designation) or located in close proximity to identify buildings which have been recognised as having heritage value as a result of scheduling under the Historic Places Act 1993 [now the HNZPTA] or in the Auckland Unitary Plan.
3.0 and Appendix D
(c) Identification and methodology for recording of Built Heritage directly affected by the construction or associated pre- and postconstruction works (i.e. within the surface designation footprint), which cannot be retained and / or adaptively re-used / partially retained. For the avoidance of doubt, the following buildings and structures may be demolished: (i) Bluestone Toilets (SCDP Category B); (ii) Beresford Toilets; (iii) Rear annex to building at 229-231 Symonds Street; and (iv) Griffiths Building. Page 8
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N/A
Historic Character Delivery Work Plan (Built Heritage Section)
(d) Identification and methodology for recording Built Heritage directly affected by the construction, or associated pre- and postconstruction, which are to be:
N/A
(i) Adaptively reused; (ii) Partially retained in design and construction; or (iii) Built heritage elements have been integrated into other elements of the City Rail. (iv) In particular, the Requiring Authority shall explore the adaptive re-use of the buildings at 51-53 Victoria Street West (known as Martha’s Corner building) with complete demolition only considered as a last resort. As guidance, an appropriate level of adaptive re-use could include retention of the façade on all street frontages or the utilisation and incorporation of elements of the building into the design: (e) How Built Heritage Buildings and Structures will be protected during construction through the use of screening or other protective measures to mitigate adverse construction effects;
5.4
(f) How mitigation or rectification of damage to Built Heritage Buildings and Structures will be addressed; and
5.5
(g) Cross references to the specific sections in the Communication and Consultation Plan which detail how the Auckland Council Heritage Department, the New Zealand Historic Places Trust [now HNZPT], and mana whenua (see condition 15) are consulted, and the communication with the general public on the management of the adverse effects relating to Built Heritage.
7.1
Building Condition Surveys 46.1
Process for Building Condition Surveys Prior to construction, as a minimum those buildings listed in Appendix One and Appendix Two or identified pursuant to Condition 41.2(b) will be considered for a building condition survey. A building condition survey will be undertaken where it is assessed that there is potential for damage to buildings or structures arising from construction as determined by an independent suitably qualified person appointed by the Requiring Authority based on the criteria below unless the relevant industry criteria applied at the time or heightened building sensitivity or other inherent building vulnerability requires it. Building damage criteria will initially be assessed in accordance with Burland, J.B. (1997) “Assessment of Risk of Damage to Buildings due to Tunnelling and Excavation”. Additional factors which may be considered in determining whether a building condition survey will be undertaken include: (a) Age of the building; (b) Construction types; (c) Foundation types; (d) General building condition; (e) Proximity to any excavation; (f) Whether the building is earthquake prone; and
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5.1
Historic Character Delivery Work Plan (Built Heritage Section) (g) Whether any basements are present in the building. 46.2
Where prior to construction it is determined that a Building Condition Survey is required in accordance with Condition 46.1, or if measurements exceed the criteria in Condition 33:
5.1
(a) The Requiring Authority shall employ a suitably qualified person to undertake the building condition surveys and that person shall be identified in the CEMP; (b) The Requiring Authority shall provide the building condition survey report to the relevant property owner within 15 working days of the survey being undertaken, and additionally it shall notify and provide the Auckland Council Consent Monitoring officer a copy of the completed survey report; (c) The Requiring Authority shall contact owners of those buildings and structures where a Building Condition Survey is to be undertaken to confirm the timing and methodology for undertaking a pre-construction condition assessment; (d) The Requiring Authority shall record all contact, correspondence and communication with owners and this shall be available on request for the Auckland Council Consent Monitoring Officer; (e) Should agreement from owners to enter property and undertake a condition assessment not be obtained within 3 months from first contact, then the Requiring Authority shall not be required under these designation conditions to undertake these assessments; (f) The Requiring Authority shall undertake a visual inspection during "active construction" if requested by the building owner where a pre-construction condition assessment has been undertaken. (g) The Requiring Authority shall develop a system of monitoring the condition of existing buildings which is commensurate with the type of the existing building and the proximity of the CRL works. The purpose of monitoring is to assess whether or not active construction is compromising the structural integrity of the building. (h) The Requiring Authority shall, during the Building Condition Survey, determine whether the building is classified as Commercial / Industrial / School or a Historic or sensitive structure in terms of Condition 33. 46.3
During construction:
5.1
(a) The Requiring Authority shall implement procedures that will appropriately respond to the information received from the monitoring system. Where necessary this may include the temporary cessation of works in close proximity to the relevant building until such time as measures are implemented to avoid further damage or compromise of the structural integrity of the building. (b) Any damage to buildings or structures shall be recorded and repaired by the Requiring Authority and costs associated with the repair will met by the Requiring Authority. 46.4
Following construction: (a) The Requiring Authority shall, within 12 months of the commencement of operation of the City Rail Link, contact owners of those buildings and structures where a Building Condition Survey was undertaken to confirm the need for undertaking a post-construction condition assessment; (b) Where a post-construction building condition survey confirms that the building has deteriorated as the result of construction or operation works relating to the City Rail Link, the Requiring Authority shall, at its own cost, rectify the damage; and
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5.1
Historic Character Delivery Work Plan (Built Heritage Section)
46.5
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Where the Requiring Authority is required to undertake building repairs in accordance with Conditions 46.3(b) or 46.4(b), such repairs shall be undertaken as soon as reasonably practicable and in consultation with the owner of the building.
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Historic Character Delivery Work Plan (Built Heritage Section)
Sustainability The Link Alliance is seeking an Infrastructure Sustainability Council of Australia (ISCA) Infrastructure Sustainability (IS) rating for the CRL project. Further details can be found in the main works CEMP and Sustainability Management Plan. Sustainability requirements that relate directly to this HC DWP are included in Appendix B. These requirements are imbedded within the Delivery Work Plans and Management Plans for the main works to ensure that sustainability is a key focus and ‘the way we do things’. In some cases, the IS requirements and sustainability goals enhance the designation requirements.
HC DWP (Built Heritage) Review and Updates This HC DWP (Built Heritage Section) is a live document that will be reviewed at least annually, or as a result of a material change to the main works, or to address unforeseen adverse effects on built heritage arising from construction, or unresolved complaints. Refer to sections 1.9 and 6.7 of the CEMP for further detail on the review and updating process.
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Historic Character Delivery Work Plan (Built Heritage Section)
2.
Mt Eden Main Works Description Overview of Works
The main works involve construction along several active work fronts concurrently within the Mt Eden area at any one time, to enable the redevelopment of Mt Eden Station and establish the CRL tie-ins to the NAL. Works will be carried out in a staged fashion. The construction staging, and methodologies are described in greater detail in the CEMP. Within the main works area, there are already other works occurring in accordance with the Mt Eden Enabling Works (OPW60350039) and Normanby Road Early Works (OPW60351423) outline plan packages. In summary, the main works involve: • •
• • • • • •
Ground improvements, in the form of deep soil mixing (contiguous piling and grout injection), within the NAL corridor between Mt Eden Road Bridge and Normanby Road; Bulk excavations and construction of retaining walls along the NAL to provide for the rail trenches and installation of new tracks. The excavation will encounter basalt, which will be removed via rock-breaking and blasting. In places, softer ground conditions are anticipated to be encountered, which may require the use of sheet piles; Construction of the eastern and western crossover structures that enable the CRL rail lines to tie-in to the NAL; Construction of the Porters Avenue and Fenton Street pedestrian and cyclist bridges; Construction of the Normanby Road grade separation bridge, including regrading of Normanby Road and realigning the Boston Road roundabout; Redevelopment of the existing NAL platform; Construction of the CRL platform and the foundations and building structures for the Mt Eden Station building and the ventilation building; and Operation of the TBM, including the conveying of spoil material from the tunnels and the refuelling and general maintenance of the TBM within CSA 4.
This HC DWP (Built Heritage Section) has been prepared for the Mt Eden Main Works. Reference should also be made to the HC DWP (Built Heritage Section) for the Mt Eden Enabling Works and the Built Heritage Memo for the Normanby Road Early Works to understand measures that will be implemented to mitigate and manage the potential cumulative effects on built heritage within the main works area as outlined in Figure 2-1.
Construction Staging and Methodology The main works will be divided into several stages within the various work areas. Generally, the works along the NAL are divided into two stages to allow works on the northern (downmain) or southern (upmain) sections to correspond with the ‘Single Line Running’ of train services through the construction area. Works within the Mt Eden station area are divided into 12 stages. Stages 1-4 have already been addressed in the Mt Eden Enabling Works outline plan package, and stages 5-12 will be undertaken as part of the main works. For the new Mt Eden Station building and ventilation building, construction Page 13
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Historic Character Delivery Work Plan (Built Heritage Section) of the foundations and building structures will be undertaken as part of stages 5-12, while the finishing of the buildings, including internal and external fittings, will be completed as part of the future public realm reinstatement.
The construction staging, and methodologies are described in sections 2.3 and 2.4 of the CEMP.
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Historic Character Delivery Work Plan (Built Heritage Section)
Site Description The main works will be undertaken near the existing Mt Eden Station and along the NAL, in an existing urban environment. The main works area is generally bounded by the NAL (south), State Highway 1 (east), Dominion Road (west), and Nikau Street (north). The main works will include construction activity along Nikau Street, Ruru Street, Porters Avenue, Fenton Street, Haultain Street, Ngahura Street, Flower Street, Shaddock Street, Mt Eden Road, Normanby Road, Boston Road and Nugent Street.
CRL Designation 2500-6 KiwiRail Designation 6300
Figure 2-1: Site and Extent of Main Works
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Historic Character Delivery Work Plan (Built Heritage Section)
3.
Built Heritage Overview Location of Identified Built Heritage in Proximity to the Mt Eden Main Works
Identified built heritage in proximity to the main works area includes scheduled historic buildings in Lauder Road and Normanby Road. These are the Mt Eden Prison, the former Colonial Ammunition Company Shot Tower, Bulk Store building and General Office (refer Figure 3-1 and Table 3-1). The main works are also in proximity to a residential area where a Residential Special Character Area Overlay applies under the AUP, including the south side of Akiraho Street and along Brentwood Avenue (refer Figure 3-1). There are additional buildings in the proximity of the main works which are considered to have heritage values, though they are not scheduled or listed heritage buildings or special character buildings. These buildings, referred as “character buildings”, have also been considered in order to fulfil the CRL project’s ISCA requirements (Appendix B), which requires “Heritage values beyond those listed in government registers have been identified, considered and addressed”. The two additional character buildings identified are located at 3 Enfield Street and 3 Akiraho Street (Table 32). Historic heritage and special character properties in proximity to the main works, within the limits of the predicted vibration and settlement contours, have been identified. Table 7.1 in the Construction Noise and Vibration Delivery Work Plan (CNV DWP) for the main works (Appendix L of the CEMP) provides setback distances to comply with the cosmetic building damage vibration risk thresholds for heritage buildings. The largest risk radius of 30 metres applies to built heritage. Table 7.2 in the CNV DWP identifies buildings as risk of cosmetic damage within the 30-metre setback distance for Heritage Buildings. Scheduled or listed historic heritage buildings or special character buildings within this distance of the main works are Mt Eden Prison (1 Lauder Rd) and former Colonial Ammunition Company (24 and 26 Normanby Road) as identified in Table 3.1 and recommended for building condition surveys in accordance with condition 41.1(b)(i) and (iii).
Figure 3-1: Map showing location of scheduled historic heritage places and the residential Special Character Area near the Mt Eden Main Works. Page 16
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Historic Character Delivery Work Plan (Built Heritage Section) Review of built heritage in proximity to the main works and potentially affected by the consented settlement contours (mechanical and consolidation settlement) as required by Condition 41.2(b)(ii) have been referred to, including: • •
Map 8 - 12, Appendix B, Built Heritage Technical Report, 2012; and Auckland City Rail Link drawings ‘Settlement Contours and Building Assessment Mechanical and Consolidation Settlement’ CRL-SYW-RME-000-DRG-2613 (Rev 4.0), 2614 (Rev 1.0), and 2615 (Rev 1.0) - Approved Resource Consent Plans dated 17/11 2016, Appendix 1 of the CRL Aotea to North Auckland Line (‘A2N’) regional resource consents.
Table 6.1 of the Groundwater and Settlement Monitoring and Contingency Plan (GSMCP) (Appendix P of the CEMP) sets out structures identified for building condition surveys in accordance with the consented settlement contours above criteria. There are no built heritage or special character buildings in Table 6.1 in proximity to the main works which meet the criteria identified above. However, an additional character building, i.e. The Horse and Trap Tavern at 3 Enfield Street, is identified in Table 6.1 due to its location within the 10mm settlement contour. The Loft at 3 Akiraho Street is also identified as a character building and located in close proximity to the 5mm settlement contour. As a result, building condition survey is recommended for the additional character buildings (not scheduled or listed) identified in Table 3-2.
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Historic Character Delivery Work Plan (Built Heritage Section) Table 3-1: Location of Scheduled Built Heritage (Mt Eden Main Works) requiring building condition survey. Ref no. In Appendix 2 to CRL Designation Address/ Building Name Conditions, if applicable 1 Lauder Road Mt Eden Mt Eden Prison -
Scheduled in AUP Schedule 14.1 in Category A, with the Prison building and basalt perimeter wall identified as the primary feature (ID 01721.) Mt Eden Prison is also listed by HNZPT in Category 1 (List number 88).
24 Normanby Road
-
Former CAC Shot Tower Scheduled in AUP Schedule 14.1 in Category A (ID 1770) Listed by Heritage New Zealand Pouhere Taonga, Category 1, List number 87.
26 Normanby Road Former Colonial Ammunition Company (CAC) Bulk Store Refer PC 31; Scheduled in AUP Schedule 14.1 in Category B A site-specific noise and vibration management plan has been prepared for 26 Normanby Rd including vibration monitoring. Note-a building condition survey is to be carried out prior to the Normanby Early Works commencing.
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Photo
Historic Character Delivery Work Plan (Built Heritage Section)
49 Normanby Road
-
Former CAC General Office Scheduled in AUP Schedule 14.1 in Category B (ID 2752) Listed by Heritage New Zealand Pouhere Taonga, Category 1, List number 9926
Table 3-2: Additional Character Buildings in close proximity to main works (fulfilling ISCA requirements) and recommended for building condition survey. 3 Enfield Street Horse and Trap Tavern -
(Settlement Contours and Building assessment Sheet 4 of 6; DRG 2613, Rev 4.0) – Properyt is within the 10mm settlement contour 3 Akiraho Street The Loft
-
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(Settlement Contours and Building assessment Sheet 4 of 6; DRG 2613, Rev 4.0) – 5mm settlement contour to rear of this property
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Historic Character Delivery Work Plan (Built Heritage Section)
Historic Streetscape and Urban Environment Elements Historic streetscape elements, including basalt kerbs, are evident in streets near the main works, including in parts of Shaddock Street, Ruru Street, Nikau Street and Ngahura Street, as well as Boston Road, Normanby Road, Porters Ave and Wynyard Road (refer to Figure 3-2).
Figure 3-2 Historic streetscape elements include basalt kerb blocks.
Historic stone walls are evident adjacent to the NAL, visible from the existing platform of Mt Eden Station (refer Figures 3-3 to 3-5). The date of these stone walls is not confirmed; however, Mt Eden Station was the first on the Kaipara railway line which was opened in March 1880.1 Modifications may have occurred over time, but the method of wall construction suggests a late 19th century period. The walls are not identified historic heritage features, nor are they identified in the CRL Designation conditions, but are interesting as early built structures in this locality.
Figure 3-3 View of historic stone wall at Mt Eden Station.
1 New Zealand Herald, 1 March 1880, p.3 and 30 March 1880, p.5 Page 20 | Mt Eden Main Works
Historic Character Delivery Work Plan (Built Heritage Section)
Figure 3-4 View of historic stone walls at Mt Eden Station.
Figure 3-5 View of historic stone walls at Mt Eden Station.
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4.
Overview of Potential Effects on Built Heritage During the Mt Eden Main Works
Unreinforced masonry buildings, including the historic heritage and special character buildings, and structures in proximity to the main works are likely to be at higher risk from the potential effects of vibration or ground movement associated with the works. These buildings may have soft mortar joints, simple foundations and connections of structural members or limited bracing. It is important to understand the specific building structure, including foundations, fabric and detailing, in order to inform the likely built heritage effects and the methods that shall be implemented during the works to avoid, remedy or mitigate these effects (outlined in Section Error! Reference source not found. of this HC DWP (Built Heritage)).
Vibration Vibration can affect nearby buildings and their foundations, with consequential damage to building fabric and services. Potential damage from vibration can range from cosmetic to minor or major damage. Potential effects on historic structures as a result of ground movement due to vibration include cosmetic or aesthetic effects such as hairline cracks to surfaces or to mortar joints that might affect appearance, through to changes to building fabric that might affect weather tightness, alignment of windows and doors, or damage to services. Major damage could place buildings at risk in terms of structural stability. For built heritage places, even aesthetic damage may impact on heritage values, for example if original details or finishes are cracked or damaged, and potentially if inappropriate repairs to such defects are undertaken. A CNV DWP (Appendix L of the CEMP) has been prepared to address the vibration effects of the main works. Some construction activities have potential to exceed the limits for construction noise and vibration at close nearby receiver distances, and therefore appropriate management and mitigation measures are to be employed to avoid exceedances.2 Construction activities required for the main works will need to be carefully managed through this DWP, and the CNV DWP in accordance with relevant conditions.
Ground Movement Excavation and foundation work can also cause ground displacement and movement of an adjacent historic structure. Excavation deeper than the foundations of neighbouring historic buildings has the potential risk of such movements occurring. A historic structure, with a shallow masonry footing, may experience corresponding displacement that can result in major structural damage. Managing the risk and potential effects of ground movement or settlement is addressed in the GSMCP (Appendix P of the CEMP). As described in section 6.2 of the GSMCP, Building Condition Surveys will be carried out for all structures listed in Appendix 2 of the A2N consent conditions that may be impacted by the main works, and buildings where the Link Alliance has assessed there is a potential for settlement and/or vibration effects within the main works area. The surveys will be undertaken to establish a baseline building condition against which any subsequent surveys can be compared. Buildings will be assessed according to foundation type, construction and sensitivity to ground movement. The 2 Section 9.3 CNV DWP Page 22 | Mt Eden Main Works
Historic Character Delivery Work Plan (Built Heritage Section) outcome of the investigations and monitoring will determine any mitigation measures to be implemented to control settlement to the building foundations.
Stormwater Drainage Maintaining a well-functioning stormwater drainage system is essential to the protection of any historic structure. This system can easily be rendered ineffective by construction or demolition work if debris originating at the construction site finds its way to the rainwater disposal system or drains of an adjacent building, with potential to adversely impact on heritage fabric through flooding.
Impact Damage Construction activities have potential to cause accidental damage to building fabric through direct impact from machinery. Appropriate protection and management are required to avoid this.
5.
Management and Mitigation Measures
Potential impacts on built heritage in proximity to construction activities are also considered as part of the CNV DWP and the GSMCP for the main works. The performance standards for construction induced settlement specified in the A2N consent conditions will be met through the specific design aspects of the main works, along with management, monitoring, mitigation and contingency measures set out in the GSMCP. Methods to be implemented during construction to avoid, manage or mitigate potential impacts on built heritage include: • Building Condition Surveys prior to the commencement of works; • Investigations of building foundations prior to the commencement of works; • Monitoring of vibration and ground/building movement, and mitigation and contingency measures as set out in the CNV DWP and GSMCP; • Built heritage protection where appropriate; and • Building record and salvage strategy (with respect to the removal of any built heritage items) (refer to Section 5.1.1 and 6 of this HC DWP (Built Heritage)).
Building Condition Surveys Pre-Construction Surveys Prior to construction, building condition surveys of heritage buildings identified in the CNV DWP and the GMSCP as being potentially impacted by the works (buildings listed above in Table 3-1) will be undertaken as part of the main works. The condition assessments will ascertain any pre-existing damage to a building, existing structural distress, and any potential weakness of the structure’s foundations or structural elements, as well as non-structural damage. The condition surveys will form the basis for recording buildings and recording baseline information prior to works commencing. The building condition surveys will generally be undertaken as follows (in accordance with CRL designation condition 46): • •
The building surveys will be undertaken by an independent senior qualified person. The survey shall include: •
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Any information about the type of foundations;
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Historic Character Delivery Work Plan (Built Heritage Section) • • • •
Existing levels of damage (aesthetic, superficial, affecting levels of serviceability); Whether observed damage is associated with structural damage; Susceptibility of building or structure to further movement; and Photographic evidence.
With respect to built heritage, the pre-construction condition surveys will include, as appropriate: • •
• • •
A survey of the exterior and interior of heritage buildings. A record of the condition of buildings using photographs, annotated drawings and written records, noting any existing signs of structural distress and damage or deterioration of a nonstructural nature. Consideration of the stability of any elements, including applied decorative elements or features, and any fragile elements. Any recommended remediation to secure or mitigate potential problems prior to the commencement of construction. The location of all cracks greater than 2 mm in aperture width, which shall be recorded with a positional accuracy of +/- 200mm. Installation of grid crack monitors may be required on selected readily accessible cracks with an aperture width greater than 2 mm discussed above and as determined in consultation with the Built Heritage Specialist.
The condition surveys shall generally include: •
• • • • • • • •
An introduction with overview of the premises, record of when the inspection was made, orientation notes for viewing photos and captions, summary of the scope of inspection, purpose of report and any limitations, any areas not accessed; A description of the property construction, based on a visual inspection and review of available architectural drawings and property information obtained from Council; A summary of existing damage and susceptibility to future damage; Site plan; Annotated plans, elevations and sections that relate to the photographic record; Floor plans if available; Burland building damage classification matrix; Pre-Construction Condition Schedule, with description, visible damage evident, damage category recorded and photograph reference; and Annotated photographs recording building condition. This should include general exterior and interior views as well as photographs of specific defects.
The pre-construction condition surveys will be reviewed by the Built Heritage Specialist, prior to works commencing.
Surveys during Construction As set out in the CNV DWP, building condition surveys may be undertaken during the construction works if complaints in relation to building damage are received or if the vibration criteria set out in the CRL designation conditions are exceeded. As set out in Section 6.2.3 of the GSMCP, during-construction, surveys will include visual inspections of the surrounding ground and external building facades of buildings for which pre-construction condition surveys are required adjacent to the works, to monitor any deterioration or movement of Page 24
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Historic Character Delivery Work Plan (Built Heritage Section) any pre-existing cracks. The GSMCP also requires continuous measurement of any ground surface or building movement during construction.
Post Construction Surveys Post-construction surveys shall comprise a repeat of the required elements of the pre-construction survey so that a direct comparison can be made. In accordance with CRL designation condition 46.4, building condition surveys of those buildings or structures that were subject to a pre-construction building condition survey may be undertaken post-construction of the main works. Where a postconstruction building condition survey confirms a building has deteriorated because of the works, the damage shall be rectified by the Link Alliance.
Building Record and Salvage Strategy No heritage or special character buildings are directly affected by the main works and therefore a salvage and building record strategy is not applicable for any buildings.
Historic Streetscape Elements and Walls As described in Section 3.2, basalt kerbs are evident in streets in the vicinity of the main works. These shall be carefully removed where required, prior to or during the works and stored for reinstatement at an appropriate time following the completion of works, as far as practicable. Historic stone walls adjacent to the NAL and visible from the platform of Mt Eden Station should be photographically recorded and material salvaged for potential reuse as part of the main works or elsewhere.
Monitoring and Management Measures Groundwater and Settlement Monitoring Based on the results of the pre-construction building condition surveys, and in accordance with the GSMCP, geotechnical and structural instrumentation will be installed in selected monitoring locations. Building Movement Monitoring Markers shall be located on identified buildings, with the property owner’s consent. The purpose of this instrumentation will be to measure/monitor any movement, settlement, tilt, and strain as a result of the works which may have the potential to adversely affect the structure. The instrumentation will be installed prior to starting the construction works. This will allow a period where initial readings and baseline monitoring readings from the instrumentation may be obtained, in order to provide baseline information. The proposed monitoring frequency and duration of the geotechnical and structural instrumentation installed on or near historic resources/structures is described in the GSMCP. Should monitoring indicate the exceedance of specified movement trigger levels, then the GSMCP also sets out an appropriate intervention and mitigation strategy.
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Historic Character Delivery Work Plan (Built Heritage Section)
Vibration Vibration mitigation and management, based on a BPO approach will be implemented during the works as outlined in the CNV DWP, including appropriate management and monitoring of construction activities and equipment. Regular monitoring and assessment of the vibration measurements will determine the process to be followed and any required action to mitigate and manage any potential effects.
Built Heritage Monitoring Periodic monitoring will be undertaken by the Built Heritage Specialist when required to review works in proximity to built heritage and respond to queries that may arise during the main works.
Managing Maintenance Works to Heritage Buildings during the Construction Works The construction team will work with building owners to facilitate necessary building maintenance and repair works during construction should monitoring/inspections confirm this is needed. The construction team will arrange the process to manage maintenance works.
Protection Methodology during Construction Activities Table 5-1 outlines the methodology to be implemented to protect key features of historic (and other) buildings against construction activities undertaken adjacent to, or near these buildings. Table 5-1: Overview of Protection Methodology
Built Heritage Feature Exterior fabric and surfaces of buildings and structures
Fragile exterior or interior building elements Historic streetscape elements
Protection Methodology Where works will be undertaken immediately adjacent to exterior fabric and surfaces of heritage buildings and structures, appropriate protection such as plywood sheets or temporary fencing to a minimum of 2 metres high will be required. Impact from machinery movement to be avoided through use of appropriate equipment and observation while works undertaken. Appropriate bracing or protection for features such as parapets or chimneys if vibration or ground settlement will be likely to put these at risk. Elements, such as basalt kerbs, shall be carefully removed if required, prior to or during the works and stored for reinstatement at an appropriate time following the completion of works.
Protection measures shall be reviewed by the Built Heritage Specialist prior to works commencing and periodically during the works.
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Historic Character Delivery Work Plan (Built Heritage Section)
Rectification Methodology The building condition surveys and assessments and monitoring/management methods outlined in section 5 of this HC DWP (Built Heritage Section) will be the vehicle for any discussion around the need for rectification works on a case by case basis.
6.
Heritage Interpretation
Where practicable, interpretive information about historic heritage in this local area should be incorporated into the main works. Heritage interpretation for the main works includes a range of measures such as use of historic photographs on site fencing and hoardings, and information on the CRL website regarding archaeology, artefacts and other discoveries made during the works. Temporary decorative lighting is another method being used to highlight heritage buildings during some parts of the works.
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Historic Character Delivery Work Plan (Built Heritage Section)
7.
General Matters Communication and Consultation
Communication with HNZPT and Auckland Council Heritage Unit (Built Heritage and Implementation) will be undertaken to ensure that any issues are addressed in a timely and transparent manner. This will cover regular updates on progress, periodic site visits, and in the event of unexpected finds or changes to agreed methodologies. Details of the communication are provided in Section 7.2.7 of the Communication and Consultation Plan for the main works (Appendix G of the CEMP). Communication with Mana Whenua has been through monthly meetings and main works updates. Specific communication with Mana Whenua will be undertaken should there be any accidental discoveries as outlined in the Historic Character DWP (Archaeology Section) and CCP Section 7.2.4.
Key Personnel Table 7-1 outline the key personnel involved in the implementation of this HC DWP (Built Heritage Section), including the main works Built Heritage Specialist, Auckland Council Heritage Unit and HNZPT and key Link Alliance personnel. Table 7-1: Contact Details
Role
Name
Built Heritage Specialist
Jane Matthews jane@mmarchitects.co.nz (027) 415 2102
Auckland Council Built Heritage Specialist
Dan Windwood dan.windwood@aucklandcouncil.govt.nz (09) 890 2130
Auckland Council Compliance and Monitoring Officer
Timothy O’Grady Timothy.ogrady@aucklandcouncil.govt.nz 021 834 584
HNZPT Built Heritage Adviser
Robin Byron rbyron@historic.org.nz (09) 307 9928
NAL Main works Managers NAL - EFC1 (and WFC2) Main works Manager - Glen Kirk NAL - EFC2 Main works Manager - Francois Pageron MTN/Mt Eden Station (and WFC1) Main works Manager – Thibaut L’Hopital
Glen Kirk Glen.kirk@linkalliance.co.nz +64 27 500 1744 Francois Pageron Francois.pageron@linkalliance.co.nz +64 22 547 9013 Thibaut L’Hopital Thibaut.l’hopital@linkalliance.co.nz +64 27 564 5756
NAL Construction Manager
Nick Adams
Environmental and Sustainability Manager
Sarah Sutherland sarah.sutherland@linkalliance.co.nz
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Historic Character Delivery Work Plan (Built Heritage Section)
Appendix A: Consultation Record A1. CLG Comments A Mt Eden CLG meeting was held on 11 May 2020 to discuss the main works and for the CLG to provide comments / feedback on the CEMP and sub-plans, including this HC DWP (Built Heritage Section). No comments were received from the CLG on this HC DWP (Built Heritage Section).
A2. IPR Comments Jeremy Salmond from Salmond Reed Architects has undertaken an Independent Peer Review of the draft HC DWP (Built Heritage Section) and had no specific comments on the content of the DWP (email communication dated 04 May 2020).
A3. Auckland Council Comments Mr Dan Windwood, Senior Specialist in Historic Character – Built Heritage, has reviewed the draft HC DWP (Built Heritage Section) and had no specific comments on the content of the DWP (email communication dated 17 April 2020).
A4. Mana Whenua The HC DWP (Built Heritage Section) was issued to Mana Whenua in May 2020 for review.
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Historic Character Delivery Work Plan (Built Heritage Section)
Appendix B: ISCA Requirements Table B identifies the ISCA Credit Requirements relevant to this HC DWP and where they are addressed in the documents. Table B: ISCA Requirements Credit
Requirement *
Relevant section
Other Relevant Information / Comments
Heritage assessment and management HER-1
Measures to minimise the adverse impacts to heritage during construction have been identified and implemented
4.0, 5.0
Adverse impacts will be minimised by specific design aspects of the main works, along with management, monitoring, mitigation and contingency measures set out in the GSMCP and CNV DWP.
HER-1 Level 1
Community heritage values have been identified through consultation and integrated into studies.
3.0, 7
Consultation with key stakeholders including Auckland Council heritage advisers has assisted in identification of places of heritage value.
HER- 1
Community and key stakeholders have participated in the heritage studies Heritage values beyond those listed in government registers have been identified, considered and addressed. Heritage has been interpreted to promote local heritage values.
3.0
Consultation with key stakeholders including Auckland Council heritage advisers has assisted in identification of places of heritage value, including places/ elements not formally identified.
Opportunities have been identified to enhance heritage values and these have been implemented.
5.0
Monitoring of heritage is undertaken at appropriate intervals during construction Monitoring and modelling demonstrates enhancements to heritage. Manawhenua undertake kaitiakitanga responsibilities
5.3.3
Level 1
Level 2
HER-1
Level 3
HER-2
Level 3
5.0
6.0
7.1
* Refer to ISCA Rating Tool for full details of the requirement
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Heritage interpretation will be developed where appropriate. Historic features within the urban context such as kerb blocks and walls will be salvaged for reuse where possible to enhance heritage values of places and their context. Periodic monitoring will be undertaken when required to review works in proximity to built heritage and respond to queries that may arise during the main works works
Historic Character Delivery Work Plan (Built Heritage Section)
Appendix C: Staging Drawings Please refer to Appendix B of the CEMP.
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Historic Character Delivery Work Plan (Built Heritage Section)
Appendix D: Historic Heritage and Special Character Buildings in Proximity to the Mt Eden Main Works Information is provided below on those heritage and special character buildings in proximity to the Mt Eden Main Works within the limits of vibration and settlement contours as shown on available drawings including: •
Map 8 and 9 of 12, Appendix B, Built Heritage Technical Report, 2012
•
Auckland City Rail Link drawing; Settlement Contours and Building Assessment Mechanical and Consolidation Settlement Sheet 4 of 6 Approved Resource Consent Plan dated 17/11 2016.
Ref no. In Appendix 2 to Address/ Building Name CRL Conditions -
Photo
26 Normanby Road, Mount Eden Former CAC Bulk Store
Legal Description (as given in Auckland Council Geomaps)
Lot 2 DP 312430
Auckland Unitary Plan (AUP) Schedule Refer PC 31; Scheduled in AUP Schedule 14.1 in 14.1 Category B AUP Upper Symonds Street Special Character Area
-
HNZPT
-
The bluestone building at 26 Normanby Road was built in 1921-22 as the bulk store for the Colonial Ammunition Company (CAC). It is located close to other structures which formed part of the CAC complex, including the Shot Tower at 24 Normanby Road and the CAC General Office at 49 Normanby Road. The bulk store was designed by architect Johnson Clark who designed a number of buildings for the CAC on the Mt Eden site including factory and magazine buildings and staff housing.
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Historic Character Delivery Work Plan (Built Heritage Section) -
24 Normanby Road, Mount Eden Former CAC Shot Tower
Legal Description (as given in Auckland Council Geomaps)
Lot 3 DP 312430
Auckland Unitary Plan (AUP) Schedule Scheduled in AUP Schedule 14.1 in Category A 14.1 (ID 1770) AUP Upper Symonds Street Special Character Area
-
HNZPT
Listed by Heritage New Zealand Pouhere Taonga, Category 1, List number 87
Refer Heritage New Zealand website: https://www.heritage.org.nz/thelist/details/87: ‘The Colonial Ammunition Company Shot Tower is the only twentieth-century shot tower in Australasia, and a rare example internationally to have been built using steelframed construction. Erected about 1916, the tower was designed to manufacture lead shot for shotgun cartridges, which were employed for sport and hunting. The structure was part of an extensive industrial complex in suburban Mt Eden, Auckland, established by the Colonial Ammunition Company (CAC) in the mid-1880s as the earliest munitions factory in Australasia.’ -
49 Normanby Road, Mount Eden Former CAC General Office
Legal Description (as given in Auckland Council Geomaps)
-
Auckland Unitary Plan (AUP) Schedule Scheduled in AUP Schedule 14.1 in Category B 14.1 (ID 2752) AUP Upper Symonds Street Special Character Area
-
HNZPT
Listed by Heritage New Zealand Pouhere Taonga, Category 1, List number 9926
Refer Heritage New Zealand website: https://www.heritage.org.nz/thelist/details/9926 ‘The purpose-designed industrial office building erected in 1916-17 for the Colonial Page 33
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Historic Character Delivery Work Plan (Built Heritage Section) Ammunition Company (CAC) in Mt Eden’s Normanby Road is a significant surviving part of Australasia’s earliest munitions factory and represents the oldest surviving component on the original site of the nineteenth-century works.’
1 Lauder Road, Mount Eden Mt Eden Prison
Legal Description (as given in Auckland Council Geomaps)
-
Auckland Unitary Plan (AUP) Schedule Scheduled in AUP Schedule 14.1 in Category A 14.1 (ID 1721) AUP Upper Symonds Street Special Character Area
-
HNZPT
Listed by Heritage New Zealand Pouhere Taonga, Category 1, List number 87
Refer Heritage New Zealand website: https://www.heritage.org.nz/thelist/details/88 In 1856 a stockade was established in the northern part of Mt Eden. Plans for a new prison were subsequently drawn up by the colonial architect P.F.M. Burrows. The prison wall was built by prison labour between 1865 and 1872 and the prison itself was begun in 1882 and completed in 1917. At the time of its completion the building had accommodation for 220 prisoners. In 1965 two prisoners began a riot which lasted for two days and left the prison burnt and uninhabitable. However, the solid stone walls survived, and the interior was rebuilt. More buildings have been subsequently added. (Franklin, E.C., Mt Eden’s First Hundred Years: Borough Golden Jubilee 1906-1956, Auckland, 1956, and Angelo, Faye M., The Changing Face of Mount Eden: A History of Mt Eden’s Development up to the Present, Auckland, 1989, pp.33-35.)
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