CRL Contract 3 Aotea Utility Relocation Work – Stages 4 & 5 Trees and Vegetation Delivery Work Plan CRL-AOT-RME-LKA-PLN-800023
Revision: 1.0 Date: 08 November 2019
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Trees and Vegetation Delivery Work Plan
Trees and Vegetation Delivery Work Plan CRL-AOT-RME-LKA-PLN-800023 This document is uncontrolled when printed. This document should be printed in colour
Revision Status Revision
Issue Date
Major Changes
1.0
8 Nov 19
For issue
Changed By
Approval Status Name/Title Prepared by:
Lyndsey Smith Principal Environmental Scientist
Reviewed by:
Fiona Davies Associate Director - Environment
Approved by:
Peter Roan Consents Lead Link Alliance
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Signature
Date
Approved By
Trees and Vegetation Delivery Work Plan
Table of contents 1. Introduction ................................................................................................4 1.1
Overview of the Stage 4 and 5 Works................................................................................ 4
1.1
Purpose and Scope ............................................................................................................ 4
1.2
Relevant Conditions .......................................................................................................... 5
1.3
DWP Review and updates ................................................................................................. 6
2. Project Description......................................................................................7 2.1
Construction Methodology.............................................................................................. 10
2.2
Roles and Responsibilities ............................................................................................... 10
3. Trees and Vegetation – CSA Works...........................................................10 3.1
Summary of trees within the Stage 4 and 5 works area .................................................. 11
3.2
Review of the Notice of Requirement (NoR) documentation .......................................... 12
3.3
Review of Tree Loss as a Result of the Over Station Development.................................. 13
3.4
Review of the CSA layout and Utilities Relocation........................................................... 14
3.5
Review of Transplanting Scheduled Trees ....................................................................... 15
3.6
Summary of Review......................................................................................................... 15
4. Mitigation Measures.................................................................................16 4.1
Trees Requiring Permanent Removal .............................................................................. 16
4.2
Tree Protection................................................................................................................ 16
4.2.1. 4.3
Tree Protection Zones and Crown Protection............................................................ 17
Tree Replacement ........................................................................................................... 18
5. Trees and Vegetation – Aotea Main Works ..............................................19 6. Consultation..............................................................................................20 7. Conclusion.................................................................................................21
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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) in the vicinity of Mt Eden Station. The CRL involves the construction of two new underground stations at Aotea and Karangahape, and a redeveloped station at Mt Eden (refer to Figure 1-1). The design and construction of the CRL infrastructure between Aotea and Mt Eden Stations is being delivered by the Link Alliance. This Trees and Vegetation Delivery Work Plan (TV DWP) has been prepared in relation to the enabling works (herein referred to as the Aotea ‘Stage 4 and 5 works’) for construction of the CRL Aotea Station.
Figure 1--1: CRL Route and Location.
1.1 Overview of the Stage 4 and 5 Works The Stage 4 and 5 works are summarised in Section 2.2 and 2.3 of the Construction Environmental Management Plan (CEMP) addendum.
1.1 Purpose and Scope In accordance with CRL designation condition 55, this TV DWP has been prepared to identify measures that will be implemented to mitigate and manage the potential adverse effects on trees and vegetation during the Stage 4 and 5 works. The objective of the TV DWP (designation condition 55.2) is: • •
To avoid the removal of scheduled trees as far as practicable; and Where trees are identified for removal during surface works the Requiring Authority will remedy or mitigate the adverse effects of construction on trees and vegetation.
This TV DWP addresses the requirements of CRL designation condition 55 and will be implemented throughout the construction period. Page 4
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Trees and Vegetation Delivery Work Plan The TV DWP has been prepared in consultation with the Aotea Community and Business Liaison Group (CLG) and has undergone independent peer review prior to submission to Auckland Council (as per designation conditions 7 and 11). A record of consultation outcomes (CLG and independent peer review) is provided in Appendix A:.
1.2 Relevant Conditions Table 1-1 identifies the designation conditions relevant to this DWP and where they are addressed in the document. Table 1-1: Trees and Vegetation conditions and DWP Section where addressed.
Condition No.
Condition
55.1
A Trees and Vegetation DWP shall be prepared to manage the adverse effects from the removal of trees and vegetation during the construction of the City Rail Link or any part of it.
55.2
The objective of the Trees and Vegetation DWP is to avoid the removal of scheduled trees as far as practicable. Where trees are identified for removal in surface works the Requiring Authority will remedy or mitigate the adverse effects of construction on trees and vegetation.
55.3
To achieve the above objective the following shall be included in the Trees and Vegetation DWP and implemented as required:
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Relevant section of DWP
1.2
(a) Confirmation of the trees to be removed due to surface construction works and whether it is appropriate and feasible to relocate or store these trees for replanting. The removal of scheduled trees which form a significant group should only be undertaken as a last resort;
Sections 3 and 4.1
(b) A list of trees, which due to being in proximity to construction works, have root systems and / or foliage within and / or overhanging the surface designation footprint, and the methods to be used, where practicable, to protect these trees from construction works;
Section 3
(c) Cross references to the Urban Design DWP and the proposed mitigation of any tree / vegetation removal through replanting trees at a 1:1 ratio, reinstatement of the area, and other methods. In preparing the Trees and Vegetation DWP, the Requiring Authority shall seek input from the Auckland Council Parks Department with regard to tree species / vegetation selection, tree pit construction where deemed necessary, and the positioning of replacement trees and from directly affected land owners with regards to preferences for any replacement planting for vegetation / trees removed from private property or for any replacement planting on private property;
Section 4.1.1
(d) Other methods to be used to monitor and report on the management of the adverse effects from tree / vegetation removal;
Section 4.1.2 and 4.2
(e) Cross references to the specific sections in the Communication and Consultation Plan which detail how the Auckland Council Parks Department, mana whenua (see condition 8) are consulted, and communication with the general public on the management of the adverse effects relating to the removal of trees and vegetation.
Section 5
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1.3 DWP Review and updates This TV DWP is a live document that will be reviewed at least annually, or as a result of a material change to the Stage 4 and 5 works, or to address unforeseen adverse effects on trees and vegetation arising from construction, or unresolved complaints. Any material changes to this TV DWP must be approved by Auckland Council prior to any on-site activity reliant upon the change commencing. Refer to Section 5.7 of the CEMP addendum for further detail on the review and updating process.
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2. Project Description In preparation for the construction of Aotea Station, and its associated tunnels, existing utilities need to be relocated and a Construction Support Area (CSA) needs to be established within the outdoor car park area to the west of Bledisloe House. The overall area of the Stage 4 and 5 works is illustrated in Figure 2-1.
Figure 2-1: Stage 4 and 5 Site Location.
The Stage 4 and 5 works involve: 路 路 路 路
The excavation of trenches to enable the relocation of existing utilities beyond the footprint of works to construct Aotea Station. Guide Wall construction involving the excavation and installation of 200mm thick temporary concrete guide walls. The removal of trees to enable the utilities to be relocated and for the establishment of the CSA. Joint bays and pulling pits to be constructed to enable directional drilling of services.
The location of utilities to be moved is shown in Figure 2-2 and the range of activities occurring within the CSA is illustrated in Appendix C: (Figure C-1 to Figure C-4). This series of drawings illustrates (indicatively) how the space within the CSA will be used at different stages of construction and includes use of Mayoral Drive (use of Mayoral Drive for the CSA will not occur during Stages 4 and 5; this will only occur during the Aotea main works).
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Figure 2--2: Location of existing utilities that are to be relocated (yellow illustrates services to be relocated, orange illustrates services that are present and will not be relocated by the Link Alliance).
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Figure 2-3: Site Layout of CSA at Bledisloe Carpark (subject to change).
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2.1 Construction Methodology The Stage 4 and 5 works will be divided into stages. A full description of the methodology associated with the Stage 4 and 5 works is provided in Section 2.3 of the CEMP addendum. This includes a description of the Stage 4 and 5 works which are beyond the scope of works described in the Approved CEMP. Staging plans and site layouts for each stage of the works are provided in Appendix C of the CEMP addendum.
2.2 Roles and Responsibilities The key personnel responsible for this TV DWP are identified in Table 2-1. All site personnel are also responsible for following the requirements of the TV DWP. Refer to the CEMP addendum for further detail on roles and responsibilities. Table 2-1 Key Personnel
Role Aotea Station Project Manager Aotea Station Construction Manager Environmental and Sustainability Manager Link Alliance Communications and Engagement Manager Project Arborist
Name Matt Cheyne Matt Sinclair Sarah Sutherland Rachel Blundell Matt Paul
3. Trees and Vegetation – CSA Works It was identified in the Tree Assessment1 accompanying the Notices of Requirement for establishment of the CRL designations and latterly confirmed via a site walkover, that there are 66 trees within the area where the CSA will be located and where utilities are required to be relocated as part of the Stage 4 and 5 works (refer Table 3-1 below for species and number of trees). These trees include 16 tulip trees located along both sides of Mayoral Drive, which form part of a group of ‘Notable Trees’ scheduled in the Auckland Unitary Plan (Operative in Part) (AUP(OP) (I.D 13). Other trees located within the Bledisloe House car park include honey locust, Queensland box gum, magnolia, titoki and cabbage tree. A review was undertaken to determine whether there was the potential to avoid or minimise the effect of the Stage 4 and 5 works on the trees within the project area. If it was identified that trees could not be retained, appropriate mitigation has been specified within this TV DWP in accordance with the designation conditions. This review includes the followings steps; · ·
·
1
Identification of trees within the footprint of the Stage 4 and 5 works (Section 3.1). Review of the Notices of Requirement (NoR) and subsequent hearing documentation to determine if the proposed tree removal is in general accordance with what was outlined at the time when the CRL designations were being established (Section 3.2). Review of tree loss that would occur as a result of the approved Over Station Development2 (Section 3.3).
City Rail Link Tree Assessment, Boffa Miskell, 9 August 2012 Aotea Over Station Development – Application for Resource Consent and Assessment of Environmental Effects, Tattico, June 2016 Page 10 | Trees and Vegetation Delivery Work Plan 2
Trees and Vegetation Delivery Work Plan · ·
Review of the layout and activities occurring within the CSA to determine if any of the Notable tulip trees proposed for removal, could be retained (Section 3.4). Review as to whether trees that need to be removed could be transplanted (Section 3.5).
This review has sought to respond to questions and concerns raised by Auckland Council’s Arborist, Howell Davies during consultation meetings held on the 2nd October 2019 and 24th October 2019. Appendix D: provides a record of the issues raised at these meetings, and a summary of how the Link Alliance will address these issues.
3.1 Summary of trees within the Stage 4 and 5 works area Trees within the Stage 4 and 5 works area are identified in Table 3-1. Their locations are shown in Figure 3-1. Table 3-1 trees within the Stage 4 and 5. Tree(s) ID
Common Tree Name
Botanical Name
Scheduled
Tree Condition
Estimated height (m)
T35
Tulip Tree
Liriodendron tulipifera
Yes
Good
6
T36
Tulip Tree
Liriodendron tulipifera
Yes
Fair
10
T37
Tulip Tree
Liriodendron tulipifera
Yes
Good
8
T38
Tulip Tree
Liriodendron tulipifera
Yes
Fair
8
T39
Tulip Tree
Liriodendron tulipifera
Yes
Good
11
T40
Tulip Tree
Liriodendron tulipifera
Yes
Fair
11
T41
Tulip Tree
Liriodendron tulipifera
Yes
Poor
7
T42
Tulip Tree
Liriodendron tulipifera
Yes
Fair
7
T43
Tulip Tree
Liriodendron tulipifera
Yes
Poor
7
T44
Tulip Tree
Liriodendron tulipifera
Yes
Fair
8
T45
Tulip Tree
Liriodendron tulipifera
Yes
Fair
5
T46
Tulip Tree
Liriodendron tulipifera
Yes
Good
13
Broadleaf x 3
Griselinia littoralis Alectryon excelsus Cordyline australis
No
Good
To 5.5
Titoki x 3
The three broadleaf trees have been removed prior to CRL.
G47 Cabbage tree
Honey Locust x 14
Gleditsia triacanthos
No
Good x 14
To 7
Queensland box tree
Lophostemon confertus
No
Good
13
Queensland box tree
Lophostemon confertus
No
Good
8
T51
Tulip Tree
Liriodendron tulipifera
Yes
Good
9
T52
Tulip Tree
Liriodendron tulipifera
Yes
Good
9
T53
Tulip Tree
Liriodendron tulipifera
Yes
Poor
6
Queensland box tree
Lophostemon confertus
No
Good
12
Tulip Tree
Liriodendron tulipifera
Yes
Poor
6
T48 T49 T50
T54 T55 Page 11
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Trees and Vegetation Delivery Work Plan
Tree(s) ID
Common Tree Name
Botanical Name
Scheduled
Tree Condition
Estimated height (m)
Queensland box tree
Lophostemon confertus
No
Fair
11
G208
Honey Locust x 2
Gleditsia triacanthos
No
Good
To 6
G209
Honey Locust x 8
Gleditsia triacanthos
No
Good
To 7
G207 /G210
Magnolia x 6
Magnolia sp.
No
Good
To 6m
G211
Magnolia x 9
Magnolia sp.
No
Good
To 7m
T56
3
Figure 3-1: Trees impacted by Stage 4 and 5 works indicated by the yellow box.
3.2 Review of the Notice of Requirement (NoR) documentation A review of the NoR and hearing documentation was undertaken in order to confirm that the tree removal proposed during the Stage 4 and 5 works is ‘in general accordance’ with the information provided when the CRL designations were established. The following documentation was reviewed by the Link Alliance; · ·
3
Auckland Council (11 June 2013) City Rail Link Notice of Requirement: Report for Hearing Commissioners (s.42A Report). Chapman. S (2013) Statement of Evidence of Simon Percival Chapman (Assessment of Effects on Trees).
Error in the referencing of trees. Tree Assessment include a dot on the map for G207, but there is no text in the associated table. On review of the trees in the ground it appears that the text for G210 relates to the Magnolia trees in the carpark marked by G207. Page 12 | Trees and Vegetation Delivery Work Plan
Trees and Vegetation Delivery Work Plan · ·
Sirl. G (2013) Arboricultural Assessment (Attachment K of the s.42A Report). Watson. A, Framsworth, M, Mead, D, Milne, P, Wheeler, G (2014) Recommendation of Independent Commissioners.
The Arboricultural Assessment produced by Sirl (2013) informed the s.42A Report prepared by Auckland Council. This s.42A Report indicated that the documentation originally submitted by Auckland Transport for the NoR identified the trees within the Bledisloe Car Park would need to be removed, and two scheduled tulip trees along Mayoral Drive may also require removal. However, the s.42A Report then went on to state: ” additional clarification of the proposed effects on trees was provided verbally by the project team on a walkover of the site on 7 May 2013’. That discussion identified that: ·
A variation to the construction work site will incorporate more of the northern end of Mayoral Drive than explicitly stated in the NoR documentation notified, meaning that up to an additional fourteen (14) scheduled Tulip trees and three (3) generally protected Queensland Box trees may also require removal.”
The s.42A report therefore acknowledged that a variation to the CSA may result in the removal of up to 16 scheduled Tulip trees as a worst case scenario. Regardless of the need to remove trees, the s.42A report stated: ”In terms of the assessment that will identify the trees that need to be removed prior to construction commencing, priority consideration should be given to retaining trees in situ, with specific reference to the sixteen (16) potentially affected scheduled Tulip trees located within the Mayoral Drive road reserve.”
In providing a recommendation on the NoRs, the independent commissioners were therefore aware of the potential need to remove up to 16 scheduled tulip trees along Mayoral Drive. The designation conditions were developed with this in mind, indicating that ‘the removal of scheduled trees which form a significant group should only be undertaken as a last resort (Condition 55.3a)’. It is therefore the responsibility of the Link Alliance to demonstrate that all practicable alternatives that avoid removal of the scheduled tulip trees have been considered.
3.3 Review of Tree Loss as a Result of the Over Station Development Resource consent was granted on 14 September 2016 (application number R/LUC/2016/2647) for an Over Station Development (OSD) at the future location of Aotea Station (Wellesley Street entrance). Implementation of the OSD consent would result in the construction of two towers and a laneway that would occupy the majority of the Bledisloe House Car Park, thus requiring removal of trees within this site. The Assessment of Environmental Effects (AEE)to support resource consent was prepared by Tattico Ltd (June 2016). The boundary of the proposed OSD site is illustrated in Figure 3-2.
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Figure 3-2 The boundary of the Over Station Development
Link Alliance undertook a review of the Tattico AEE to confirm the extent of tree removal required for the OSD development. This review indicated that the removal of trees within the Bledisloe car park site was not discussed within the AEE. From further research, Link Alliance understands that the reason tree removal was omitted from this AEE was because it was assumed that CRL construction activities would have already removed the existing trees. Given the trees within the car park site would inevitably be removed as result of the CRL construction activities, or the approved OSD development, the retention of trees or deferring removal of trees to a later date, within the car park site would be of little value. None of the trees within the Bledisloe carpark site are scheduled and the removal of these trees would be a Permitted activity under the AUP(OP). However, the Tattico AEE indicated that the OSD development would not impact on the Tulip trees along Mayoral Drive, and therefore Link Alliance must demonstrate that there is no practicable alternative to avoid the removal of these notable trees, and if removed, must provide adequate mitigation in compliance with the designation conditions. This mitigation would be in the form of planting undertaken as part of the future public realm (streetscape) reinstatement on completion of Aotea Station construction works. This public realm reinstatement will be addressed in a future ‘Urban Design Delivery Work Plan’ to be submitted to Auckland Council as part of a separate Outline Plan.
3.4 Review of the CSA layout and Utilities Relocation A review of the CSA layout and the utilities was undertaken by the Link Alliance to identify whether there were opportunities to retain the 16 notable tulip trees proposed to be removed along Mayoral Drive. Link Alliance reviewed the potential for relocating the surge pile (refer figure 2-3 above) that has been proposed to be positioned where trees T43 – 46 are located (refer figure 3-1 above). A surge pile is typically a 2-3 m deep pit where spoil is stored. Given the significant volume of spoil that Page 14
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Trees and Vegetation Delivery Work Plan needs to be removed to construct the Aotea station, the surge pile needs to be easily accessible to large truck and trailer units and situated in a location that does not conflict with other construction activities. To achieve sufficient storage volume for the proposed works, the footprint of the surge pile (including the excavator and truck access) needs to be approximately 360 m2. Link Alliance reviewed the potential for relocating the surge pile to the northern end of the CSA in order to retain the titoki trees (G47). These trees are native species, and although not scheduled under the AUP(OP), were recognised as being healthy and mature trees by the Auckland Council arborist. However, it was determined that relocation of the surge pile (from its current planned location – refer Figure 2-3) would conflict with other construction activities. This is because the northern end of the CSA will be occupied by a tower crane (refer to Figure 2-3) required to support the construction of the Wellesley Street Plant Building. Excavations around this crane need to be avoided and the amount of flat level ground needs to be maximised to store materials or unload delivery vehicles. To construct the surge pile at this location would require ground to be excavated to create the pit, and this would conflict with the operation of the crane. It was therefore concluded that the surge pile could not be relocated from its current position to the northern end of the compound. Link Alliance also reviewed the potential for moving the footprint of the bentonite processing facility (refer CSA drawings at Appendix C:) further west on Mayoral Avenue to avoid impacts to the tulip trees. It was identified that there was insufficient space to do this. As a result of reviewing the CSA layout, Link Alliance identified that it is possible to retain two of the scheduled tulip trees to the west of Mayoral Drive (T51 and T52). Fourteen tulip trees will still need to be removed, resulting in an improved retention of 2 trees compared to what was originally discussed during the designation hearing (refer to Section 3.2).
3.5 Review of Transplanting Scheduled Trees Link Alliance reviewed the potential for transplanting the notable trees along Mayoral Drive. It was identified that the utilities beneath the tulip trees pose a significant constraint to the trees being transplanted given the variety of utilities present, and the likely extent of root entanglement with these utilities. Figure 2-2 (above) illustrates that electricity, wastewater, stormwater, gas, telecommunications and potable water utilities are located beneath then tulip trees that are required to be removed. The depth of these utilities will vary, but they will include utilities within 1.5 m of ground level. Howell Davies (Auckland Council, Arborist) confirmed at the meeting held on 24th October 2019, that the trees will be in a concrete root barrier / container in the first 500 mm to 1000 mm beneath ground level. The purpose of this barrier is to avoid damage to surrounding paving, however, tree roots are likely to extend through this structure and below it to reach the surrounding soil (refer Appendix D: for meeting memo). It is therefore anticipated that the roots of the tulip trees will be intermingled with the utilities. Given the extent of utilities beneath the tulip trees and the likelihood that the roots of the tulip trees are interwoven with the utilities, it is considered that the tulip trees are unable to be successfully transplanted.
3.6 Summary of Review Link Alliance has reviewed options for avoiding the loss of trees or to minimise affects on trees within the vicinity of the Stage 4 and 5 works. Page 15
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Trees and Vegetation Delivery Work Plan It was identified that at the time of the designation hearing the commissioners were aware that there was the potential for 16 scheduled tulip trees to be removed along Mayoral Drive as a ‘worst case scenario’. A review of the approved resource consent documentation for the OSD determined that all trees within Bledisloe House car park would require to be removed, be it as a result of CRL construction activities, or from the future OSD. The Link Alliance consequently explored options for the reconfiguration of the CSA to see if there was the potential to retain scheduled trees along Mayoral Drive, particularly a group of three tikoki trees (G47, located in the car park and not scheduled, however are of reasonable importance to Auckland Council4) and a large tulip tree (T46). It was concluded that there was insufficient space to retain all of the trees along Mayoral Drive. The review identified that two of the tulip trees (T51 and T52) to the west of Mayoral Drive could be retained but the remaining 14 tulip trees would need to be removed. To minimise affects, the potential to transplant the trees identified for removal was assessed. It was determined that the presence of utilities within 1.5m of ground level would mean that the roots of the trees would be interlaced with these utilities. Therefore, the successful translocation of the trees was not considered a practical option.
4. Mitigation Measures Measures have been proposed to mitigate the loss of the identified trees in Section 3.1 of this TV DWP. It is noted that all works involving removal of trees or protection of trees (working within rootzones) will be overseen by the project Arborist (refer Table 2-1).
4.1 Trees Requiring Permanent Removal The removal of trees will be undertaken by a suitably qualified arborist. The approach used will be informed by the arborist in accordance with site observations, such as the proximity of surrounding buildings, tree size and overall condition. The methodologies to be implemented will include:
· · ·
Staged removal whereby the outer limbs are removed first, followed by inner limbs and the main trunk. Depending on the location of utility lines, tree stumps should either be dug out or ground out in situ. Removed tree debris will either be mulched onsite or removed for mulching offsite, depending on which is more practicable.
4.2 Tree Protection Trees referenced as T51 and T52 have been identified for retention (with potential pruning required) following a review of the CSA layout during the Stage 4 and 5 works. There is the potential for these trees to be impacted as a result of truck and other large vehicle movements, therefore the following protection methods will be implemented.
4
Personnel communication by Howell Davies (24th October 2019). Page 16 | Trees and Vegetation Delivery Work Plan
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4.2.1. Tree Protection Zones and Crown Protection Tree Protections Zones shall be established around each tree to ensure the trunks, roots, canopy and branches are protected during the Stage 4 and 5 works. The Tree Protection Zone encompasses the root and crown area of the tree, with this area needing to remain isolated from construction disturbance in order to maintain tree health. The height of the Protection Zone is dictated by the height of the tree and the width (or radius) around the tree is typically calculated by multiplying the tree’s diameter at breast height (DBH) by 12 (AS 4970-2009): Tree Protection Zone = DBH x 12 The Tree Protection Zone will not be less than 2m nor greater than 15m, except where crown protection is required. If a tree is multi-stemmed at 1.4m above the ground (refer to Figure 4-1) the Australian Standard (AS4970-2009) indicates that in this situation the following equation should be used to determine the DBH, which would then feed into the equation above to calculate the Tree Protection Zone:
Figure 4-1: Tree forks below 1.4m where the arborist would measure DBH (AS4970-2009).
The information needed for this calculation was not been provided within the original arboricultural assessment of trees (Boffa Miskell, 2012), and therefore a site visit will be undertaken to obtain the measures needed to determine the Tree Protection Zone. This is important given the trees would have experienced growth since their initial measurements were taken for the 2012 assessment. Crown protection will also be required to ensure that the trees do not receive injury from machinery such as excavators, drilling rigs, cranes, trucks and hoarding installation. Crown protection will be located 1m outside of the perimeter of the crown, which may be within the Tree Protection Zone.
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Figure 4-2: Indicative Tree Protection Zone (AS4970-2009).
The following activities will not be permitted in the Tree Protection Zones: · · · · · · ·
Mechanical excavation on the road, footpath or any public space. Stockpiling of building materials, debris or soil. Vehicular traffic except on existing paved surfaces. Installation of service pits or hatches. Vehicular crossings. Severing of tree roots with a diameter greater than 30mm. Alteration of soil levels and structure.
4.3 Tree Replacement Replacement planting will be required for the trees identified for removal (refer Figure 3-1 and Table 3-1 above). As the Stage 4 and 5 works will result in the loss of 14 scheduled tulip trees, the Link Alliance Urban Design team are currently reviewing the space that will be available on completion of Aotea Station, for planting replacement tulip trees. The removal of tulip trees along Mayoral Drive as a result of the works will result in a reduction in the ‘avenue effect’ that is currently created by this group of trees. Therefore, the replacement tulip trees will need to be arranged in a way that, as far as possible, Page 18
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Trees and Vegetation Delivery Work Plan reinstates and reinforces the ‘avenue’ effect. The Urban Design team are seeking to plant trees that will reach the same shape and form as the remainder of the tulip trees along Mayoral Drive (refer to Appendix B:), and this will require sufficient space both above and below ground. The Link Alliance are currently looking at how utilities will be placed within the road and footpath to enable the newly planted trees to reach maturity without compromising underground utilities. It was agreed during the meeting with Council Arborist, Howell Davies, that further information about utilities and replacement tulip trees in the desired locality, will be provided with the Aotea Station Main Works TV DWP, to be submitted early 2020. Detailed information about project wide urban realm reinstatement, including within the Aotea construction area, will be provided by way of separate Urban Design DWP in late 2022/23. In total, 66 trees will be lost as a result of the Stage 4 and 5 works, and in accordance with the designation conditions, these will be replaced on a 1:1 basis. It was discussed at the meeting held with Council Arborist (Howell Davies) on the 24th October, that it will not be possible to replace all of the tulip trees in the immediate vicinity of Aotea Station at a 1:1 ratio given the space constraints (the future OSD and Aotea station occupies part of the site formally occupied by tulip trees proposed to be removed). However, all trees removed will be replaced within the designation corridor. One key area where trees will be planted to mitigate for the effects of tree loss resulting from CRL construction is at the new Mount Eden Station. In addition, it was identified during consultation meetings with Auckland Council (24th October 2019) that there could also be an opportunity to replace trees along Mayoral Drive outside of the designation area, and this would contribute to the desired ‘avenue effect’. The Urban Design DWP will include detailed replanting plans for the reinstatement of the area and will include (but may not be limited to) the measures detailed below:
·
· ·
Replace removed trees on site at least at a 1:1 ratio, using large grade replacement trees to accelerate establishment. Trees will be inspected and approved by the Auckland Council’s Urban Forestry Advisor prior to planting. Consult with Auckland Council Parks Department with regard to tree species / vegetation selection, tree pit construction and positioning of replacement trees. The Urban Design DWP will include details of maintenance periods and responsibilities (i.e. the Requiring Authority for a period of five years for specimen trees and 3 years for all other landscape planting).
5. Trees and Vegetation – Aotea Main Works The Aotea main works will overlap with the working areas for the Stage 1-3 and Stage 4 and 5 ‘early’ works. Consequently, tree removals within the majority of the Project area for the Aotea main works will already have occurred, and these losses are discussed in this report (Stage 4 and 5 TV DWP) and the Stage 1 to 3 TV DWP. The only additional tree loss that will be required as a result of the Aotea main works are 11 pohutukawa trees located in a raised bed along the front of the Crowne Plaza hotel at 128 Albert Street, and these are referenced in the tree assessment report completed by Boffa Miskell5 as T43 (refer Table 5-1 and Figure 5-1).
5
City Rail Link Tree Assessment, Boffa Miskell, 9 August 2012 Page 19 | Trees and Vegetation Delivery Work Plan
Trees and Vegetation Delivery Work Plan This row of trees will need to be removed during the Aotea main works along Albert Street. The transplanting of some or all of these trees will be reviewed and will form part of the TV DWP for the Aotea main works. Table 5-1: Trees within the Aotea Station Main Works. Tree(s) ID T34
Common Tree Name Pohutukawa x 11
Botanical Name Metrosideros excelsa
Scheduled
Tree Condition
Estimated height (m)
No
Good
7
Figure 5-1: 11 pohutukawa trees along the front of The Crown Plaza hotel on Albert Street.
The Link Alliance understands the need to consider the project wide effects from loss of trees required to construct the CRL. In accordance with the designation conditions separate Urban Design DWPs will be prepared for each station area (Aotea, Karangahape and Mt Eden), this will detail how trees lost as a result of the CRL Project will be reinstated at a 1:1 ratio (urban realm reinstatement). A tree register is being kept to document trees lost across the entire CRL Project.
6. Consultation A Communication and Consultation Plan (CCP) has been prepared for the Stage 4 and 5 works (Appendix K of the CEMP addendum). Section 6 of the CCP outlines procedures for Link Alliance consultation with the Auckland Council Parks Department and mana whenua. It also details the communication that will be undertaken with the general public (through the CLG) on the management of the adverse effects relating to the removal of trees within the works area. Page 20
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Trees and Vegetation Delivery Work Plan Link Alliance also met with Auckland Council Arborist, Howell Davies, on two separate occasions (2nd October and 24th October) to discuss the trees proposed to be removed during the Stage 4 and 5 works, and how the effects from the loss of these trees will be adequately mitigated. A memo from the 24th October, summarising the issues raised and how they will be addressed, is provided as Appendix D.
7. Conclusion A total of 66 trees (including 14 notable tulip trees) are required to be removed as a result of the Stage 4 and 5 works. Link Alliance considered a number of options to limit the loss of trees, however, the best practicable option for the construction of the Aotea station requires the removal of these trees. Discussions in relation to the layout of the CSA, construction activities required within the CSA, and whether changes could be made to retain trees, were had with Council Arborist, Howell Davies on the 2nd and 24th of October 2019. These discussions determined that two tulip trees (T51 and T52) could potentially be retained, however the remaining trees would be lost. Protection of these two tulip trees aid in mitigating the loss of trees along Mayoral Drive resulting from the Stage 4 and 5 works. Tulip trees will be replaced to reinforce the avenue effect along Mayoral Drive, and loss of trees within the Bledisloe House car park (and project wide) will be replaced within the CRL designation at a 1:1 ratio. Replacement planting will be addressed in separate Urban Design DWPs prepared for each Station area which will provide detail relating to the public realm (streetscape) reinstatement across the CRL project area; these will likely be submitted in late 2022/2023.
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Trees and Vegetation Delivery Work Plan
List of Appendices Appendix A: Record of Community and Business Liaison Group consultation and independent peer review comments ........................................................................ 23 Appendix B: Indicative Public Realm Reinstatement Concept................................. 24 Appendix C: Indicative Construction Support Area layout drawings ....................... 25 Appendix D: Memo from the Auckland Council meeting on the 24th October 2019 27
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Trees and Vegetation Delivery Work Plan
Record of Community and Business Liaison Group consultation and independent peer review comments
Appendix A:
CLG Comments A Community and Business Liaison Group (CLG) meeting for the Stage 4 and 5 works was held on 30th September 2019 at the CRL office (AMP building). No comments were received form the CLG that required changes to the Trees and Vegetation DWP.
Independent Peer Review Page no.
DWP section
16
4
19
4.3
19
5
Paragraph/ sentence It is noted that all works involving removal of trees or protection of trees (working within driplines) will be overseen by the project Arborist (refer Table 2-1).
Comment
Resolution
Best to use rootzones as opposed to driplines as ‘dripline’ is no longer in the AUP terminology.
Changed terminology to indicate ‘rootzone’
Replace removed trees on site at least at a 1:1 ratio, using semi-mature trees to accelerate establishment. Trees will be inspected and approved by the Auckland Council’s Urban Forestry Advisor prior to planting. The only additional tree loss that will be required as a result of the Aotea main works are 11 pohutukawa trees located in a raised bed along the front of the Crowne Plaza hotel at 128 Albert Street, and these are referenced in the tree assessment report completed by Boffa Miskell as T43 (refer Table 5-1 and Figure 5-1).
Might be better to say ‘large grade’ replacement trees
Replaced ‘semi mature trees’ with ‘large grade replacement trees’.
I take it that these trees were not included in the Stage 1-3 TV DWP?
Yes correct, the 11 pohutukawa trees were not affected by the Stage 1 -3 works, and therefore were not included in that package of works. They will be affected by the main works, and therefore will be included in the Aotea Main works OPW.
Auckland Council Meetings were held with Auckland Council Arborist (Howell Davies) on the 2nd and 24th of October. Issues raised and responses to those issues have been recorded in a memo, attached as Appendix D:.
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Trees and Vegetation Delivery Work Plan
Appendix B: Indicative Public Realm Reinstatement
Concept
Figure which indicates the initial concept proposal for tree setting-out, to be developed by the Link Alliance within the Aotea Station Main Works TV DWP.
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Trees and Vegetation Delivery Work Plan
Appendix C: Indicative Construction Support Area
layout drawings Indicative Layout of CSA space indicating variety of Construction Activities
Figure C-1: Layout of the CSA, which is constrained by surrounding land use and the proposed station
Figure C-2: Load out from Wellesley Building Page 25
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Trees and Vegetation Delivery Work Plan
Figure C-3: Stabilised Block
Figure C-4: TBM Removal
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Trees and Vegetation Delivery Work Plan
Appendix D: Memo from the Auckland Council
meeting on the 24th October 2019
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Memo
MEETING DATE
24 October 2019
SUBJECT
Meeting re Issues and mitigation - tree removals during Stage 4 and 5 Aotea early works
LINK ALLIANCE & CRLL ATTENDEES
Craig Mathieson (CM) (Planner), Jarrod Snowsill (JS) (Planner), Richard Jenkins (RJ) (Planner), Alan Whitley (AW) (Urban design), Simon Lough (SL) (Urban design), Lyndsey Smith (LS) (Ecology), Matt Cheyne (MC) (Project engineer).
AUCKLAND COUNCIL ATTENDEES
Howell Davies (HD) (Arborist).
Action.
Description.
Outcome from meeting
Review of original NoR documents
Section 9.13 of the Section 42A Report and Grant Sirl’s assessment identified up to “sixteen (16) scheduled Tulip trees and three (3) Queensland Box trees may require removal” for the CRL works in proximity to Mayoral Drive.
Review of documentation confirmed NoR indicated up to 16 Tulip trees would potentially need to be removed. Fourteen are currently proposed for removal, and two (T51 and T52) may be retained (with some pruning). Link Alliance to indicate how the loss of the ‘avenue effect’ along Mayoral Drive will be mitigated. Main works TV DWP to include ‘indicative urban reinstatement plan’ with detail on how Tulip trees can be replaced (which take into account existing utilities beneath the pavement). RJ provided HD with a copy of Council s42A reports and relevant evidence from the hearing (by email 25/10/19).
Onus is on CRLL/Link Alliance to justify that removal of fourteen (14) of the Tulip trees is required – including adequate consideration of all practicable alternatives.
Understand the utilities beneath the site
Plan provided indicating extent of utilities beneath the Mayoral Drive site. This indicates it would prove costly to transplant the tree’s and would involve significant disruption to services. Indicative urban reinstatement plan provided, indicating where Tulip trees can be replaced. This is an indicative plan only but outlines the Link Alliance’s commitment to replacing trees of a size, scale and spacing which provides the desired avenue effect along Mayoral Drive.
Utilities adjacent to the proposed station box may be subject to realignment. No realignment is proposed of utilities further; This may have an impact on future replacement of Tulip trees. Current Tulip trees are located in ‘concrete bunker pits’, these are unlikely suitable for transplantation. Link Alliance to investigate potential to provide ‘tree pits’ which traverse under the roadway of Mayoral Drive in order to avoid utilities - results of these investigations to be provided with main works OPW. Acknowledgement that utility providers are a big risk to tree replacement – tree pit design in relation to these utilities is therefore critical. Howell to provide information on tree pits. Main works OPW will provide detail surrounding tree pit design in relation to utilities. Further information surrounding tree replacement works and urban realm reinstatement will be provided with a separate
Link Alliance – 12 Morgan Street, Newmarket, Auckland Central 1023
Memo
Action.
Description.
Outcome from meeting OPW to be submitted at a later date after the main works OPW.
Reshuffle the current layout of the CSA
The scope of works during Stage 4 & 5 includes following:
Trees need to be cleared starting December 2019 within the Bledisloe carpark site to ensure the site and equipment can be set up in preparation for the Aotea main works. This is essential if main works are to start as programmed.
Activity
Completion Date
Site Possession of Bledisloe Carpark
Dec-19
Construction of Site Fencing and Hoarding
Dec-19
Tree Clearance
Dec-19
Site Compound Establishment – Retaining Walls, Temporary Building Installation, Surge Pile etc. Bentonite Support Establishment – Treatment Plant + Storage Tank Install D-Wall Establishment Works – Guide Walls + Working Platform
Mar-20
Link Alliance will aim to retain Two Tulip trees (T51 and T52) with potential pruning. Stage 4 and 5 TV DWP to provide confirmation as to how these trees will be protected.
Mar-20 Mar-20
These activities are precursors to starting the main works, set to commence in March 2020. Clearance of trees is required to enable this site establishment to commence, and for main construction works to start as programmed.
Plan indicating sequencing of the CSA
Oversite Development Consent
Phases of the CSA has been provided to indicate how space within the site will be utilised. The OPW document for the Stage 4 and 5 and main works will indicate a CSA plan with a clear list of activities occurring within the site. This full site area is required to enable effective operation of the CSA needed to service the construction of the Aotea station and tunnels.
Agreement that current layout of the CSA provides most efficient use for activities being undertaken within the site.
Resource consent was granted on 14 September 2016 (application number R/LUC/2016/2647) for an oversite development (OSD) at the future location of Aotea Station Wellesley Street entrance. The OSD consent would result in the creation of two towers and laneway that would occupy the current Bledisloe House Car Park.
Confirmed that all trees within Bledisloe carpark will be cleared.
Plan of CSA layout (with list of activities) to be provided with Stage 4 and 5 OPW documentation. Main works CSA layout will provide confirmation of digger within the site.
It was discussed whether the three Titoki trees (G47) could be retained. However, given the approved OSD consent confirmed that these trees would be removed.
Link Alliance – 12 Morgan Street, Newmarket, Auckland Central 1023
Memo
Action.
Description. The AEE for the OSD proposal does not include or discuss the removal of trees from the car park site. It is considered responsibility of CRLL to remove the trees within the carpark site, and therefore provide 1:1 reinstatement as required under the designation conditions. Given the limited amount of space within the Aotea Project site, the majority of this reinstatement will occur in the Mt Eden and Karangahape Project sites.
Outcome from meeting Also agreed that transplantation of these trees was not practicable, given it would result in significant delay in current construction programme and the costs associated with this delay.
Surge pile
A surge pile is typically a 2-3m deep pit where spoil is stockpiled. To achieve a satisfactory storage volume, the footprint of the surge pile (incl. excavator and truck access) needs to be 360m2. This limits the suitable locations for the surge pile within the 1800m 2 CSA area.
MC outlined why the planned location of the surge pile was the most efficient location in relation to removal of spoil from the Aotea station construction site and would provide the least conflict with other activities occurring within the CSA.
The Southern end of the compound has a steep slope behind the old bus stop. This provides the correct natural topography to construct the surge pile as we will not need to excavate the full footprint to depth. This reduces the extent of the excavation required for the surge pile and assists with limiting the backfilling required for reinstatement. Establishment of this area during the Stage 4 and 5 works allows it to be in operation for the beginning of March 2020 and have no adverse impacts on the construction programme.
Acknowledgement that the current location of the proposed surge pile would require removal of the Titoki trees (G47).
Simon Lough has been speaking with AT to understand whether any future AT projects in the vicinity would affect the future replacement of Tulip trees along Mayoral Drive. AT are aware that trees will need to be removed and replaced along Mayoral Drive. AT has indicated any future plans of the bus station will work around the replacement trees (not vice versa).
AT is aware of plans to reinstate trees along Mayoral Drive.
What are AT’s future plans for this space?
Link Alliance – 12 Morgan Street, Newmarket, Auckland Central 1023
Memo
Action.
Description.
Outcome from meeting
Urban reinstatement plan
Alan Whitley has provided an indicative urban reinstatement plan. Tulip trees will be placed in ‘Tree Pits’ in order to avoid root entanglement with utilities. The trees are evenly spaced to create the desired ‘avenue effect’ will be able to grow to the desired height and scale, takes into account future plans from AT, and provides sufficient road and footpath availability for the public.
Indicative urban reinstatement plan provided. However, AW acknowledged that this did not take into account services; this was because project engineers have as yet not confirmed location of services at this time, and whether a replacement Tulip tree of the desired height and scale could be achieved. Acknowledged that greater certainty surrounding this would be provided with the main works OPW.. Agreed that 1:1 reinstatement of Tulip trees within the locality is unachievable (given future OSD and Aotea station occupies part of the site formally occupied by Tulip proposed to be removed). Link Alliance and Council (HD) will investigate opportunities to plant Tulips further up Mayoral Drive (perhaps outside of the designation) in order to achieve the desired ‘avenue effect’. Future reinstatement likely to involve consistent alignment of Tulip trees, which is an improvement to the former (Tulip trees separated by the odd Queensland box tree).
Grow tulip seedlings – draw up procurement contract
We have contacted nurseries to investigate their availability of Tulip Trees. One nursery in particular confirmed stock for 400l / 6m+ tulips which could be used as reinstatement trees.
Agreed that established Tulip trees could be sourced from Auckland nurseries and used as suitable replacement trees.
Qualified Arborist
We are in the process of on-boarding Matt Paul, qualified arborist from Peers Brown Miller.
Project Arborist engaged by Link Alliance.
TBM route and effect on Vincent Street trees
NZTA’s over dimensional route traverses up Vincent Street. The TBM will be transported in parts on a flatbed truck with the biggest piece (full cylinder) measuring 7 meters by 4.5 meters max high). This is unlikely to affect any trees on the route.
Agreed TBM route is unlikely to affect trees along Vincent Street.
TV DWP Stage 4 and 5
The TV DWP has been updated to reflect how actions have been addressed, and to ensure methodical thinking as to why trees are required to be removed, which aligns with the designation conditions (55).
Agreed that final version of TV DWP would include narrative of issues raised above and how they would be addressed. Final TV DWP document to be submitted to Council week of 4th November.
Link Alliance – 12 Morgan Street, Newmarket, Auckland Central 1023