Rezoning Submission - Appendix G Children s and Women s Health Centre of British Columbia. app.g-1

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5 SITE 1: PROPOSED CHILD CARE CENTRE April 28, 2011 Attn.: Kari Madsen Dysarchitecture Burrard Street Vancouver, BC V6J 3G7 cc: ACL File: Project Ref: Site 1: Proposed Child Care Centre Children s and Women s Hospital, 4500 Oak Street, Vancouver Re: Dear Kari, Preliminary Tree Retention Assessment Report Arbortech Consulting Ltd has been retained to undertake a detailed study of the existing trees located on or within close proximity to the above noted site to determine their current condition and to make preservation and protection recommendations in context to the proposed land use changes. Staff from this office visited the site on April 26, 2011 to inspect the trees. The tree location and topographic plan as well as the approximate area of the proposed footprint for the project have been provided for our use in completing this report. The final design and layout details may impact on the safe retention of selected trees. Outstanding details are but are not limited to; final building footprint, unknown geo-technical conditions, final grades, unknown above and below ground servicing locations, hard and soft landscaping etc. Note that if any changes to the tree retention scheme, or if any encroachments into the protection areas are deemed to be necessary for purposes, that they are subject to approvals in advance by the city and/or the project arborist. The tree condition data and the preliminary tree retention recommendations are compiled herein and on the enclosures. PRELIMINARY RETENTION REVIEW All bylaw trees located on or within close proximity to the development site have been assessed using Visual Tree Assessment (VTA) procedures. Trees have also been tagged with a serial number as referenced in this report, on the attached tree retention plan, and for future reference within the design, approval and phases of the project. In general terms, the existing trees located on this site consist of mixture of deciduous and conifer species that form part of the original landscape tree planting associated with the hospital site. The subject trees consist of twelve London plane and five Norway spruce planted on earth mound to the southern site boundary line to West 32 nd Avenue. In particular, the London plane trees form a feature linear group to the property line and road. However, this linear feature is beginning to be fragmented from historic tree removal. The five Norway spruce have developed dense branching whorls and are beginning to suffer branch breakout from this season s heavy cone crop. These Spruce trees are therefore considered to have limited future potential in context with the site usage. Please note; the far eastern tree and the concrete pathway to the east of tree # 215 detailed on the supplied topographical drawing have been previously removed. Further, off-site to the southern boundary line of the subject site, a new concrete sidewalk has been constructed that marginally encroaches within the southern root protection areas of the on-site London plane tree # s 215, 216, 217, 218, 219, 220, 221 and 222. A photographic record of the subject trees is on file. The trees are detailed as follows. The subject trees have been compiled in a Tree Inventory List where we present the tree specific data and observations. In addition, we have rated the condition of the trees based on both health and structure factors that guide us in determining the value and viability of retaining the trees. The Preliminary Tree Retention Drawing shows the location and proposed treatment of the subject trees. Both documents are included as attachments to this report and should be referenced by the reader for applicable details. On this site, the proposed development and consists of a Child Care Centre and associated hard and soft landscaping. The assessed trees have been assigned a rating as to their overall condition considering the current health and the current structural integrity of the tree. These trees were rated based on their current condition in relation to their value and viability for retention for consideration in the proposed land use. The viability ratings are summarized as follows. Table 1. TREE RETENTION VIABILITY SUMMARY, ON-SITE TREES ONLY 4 Marginal Trees: Trees that have structural defects or health concerns that are restorable with reasonable and practical treatments, and would be expected to survive impacts. The preservation of these marginal rated trees would be conditional to detailed review as well as contingencies for special measures. 13 Viable Trees: Trees that have no overt and significant defects or health issues, and that are well suited for retention. SUITE CHATHAM STREET RICHMOND BC V7E 2Z3 P F E trees@arbortech.bc.ca ARBORTECH CONSULTING LTD PAGE 2 OF 5 APRIL 28, 2011 app.g-5

6 SITE 1: PROPOSED CHILD CARE CENTRE SITE 1: PROPOSED CHILD CARE CENTRE RECOMMENDATIONS In context to the proposed land use changes, the existing trees are recommended to be treated as follows: Retain and Protect 8 trees Tree # s: 215, 216, 217, 218, 219, 220, 221 and 222 These trees form part of a larger linear feature group to the southern boundary line and will provide softening and screening to the proposed Child Care Centre from views outside the site. The proposed re-grading to remove the berm to the north of the trees will require review of the final design details and arboricultural supervision during any approved works to minimise damage and encroachment into the root zones. Pursuant to the tree protection guidelines noted below and on the attached drawing, these trees could be preserved within the project. Remove 9 Trees for Construction Tree # s: 223, 224, 225, 226, 227, 228, 229, 230 and 231 Of the 9 trees, two trees are categorised as marginal viability for retention. While these trees are young and of a relatively sound and healthy condition, they are of a size where transplanting to new positions within the site would not be practical or a cost effective option to new tree planting. Retained Trees that require Pruning Tree # s: 218 and 220 These trees require remedial pruning of selected stems to maintain their future structural integrity. See Tree List Other Treatments for details. Tree Protection Fencing. Tree protection fences must be erected as shown on the tree retention plan and restriction implemented as per the guidelines below to maintain compliance with the City of Vancouver Tree Protection Bylaw No It is recognized that certain unpredictable conflicts may arise that could interfere with the safe retention of the selected trees. Examples include but are not limited to; unknown geo-technical conditions, unknown underground servicing locations, etc. Note that if any changes to the tree retention scheme, or if any encroachments into the protection areas are deemed to be necessary for purposes, that they are subject to approvals in advance by the city and/or the project arborist. Tree Replacement. City requirements will dictate the required quantity of replacement trees for this project. Among other factors, the size and land use of the property as well as the presence of retained trees must be considered in determining the available space for planting. Those determinations will be subject to direction and/or approval by the city. Specifications for replacement trees will be provided by the project landscape consultant. Permitting. The removal of any bylaw trees will require that a permit is issued by the city. Application is made concurrently with the re-zoning and/or building permit application. Inspection Regime In respect to good arboricultural management and in context with the site usage, it is recommended that the retained tree are inspected post development impact and circa every 2 years thereafter to monitor health and structural integrity. In particular tree # s 218 and 220 have noted structural defects that require inspection and monitoring. TREE PROTECTION GUIDELINES 1. Tree Protection: a) All retained trees must be protected to meet Municipal and/or Arbortech specifications. The minimum standard for fence type that is required is detailed above. b) The tree protection fencing should be inspected and approved by the municipality and/or the project arborist prior to any demolition, site preparation or work commencing. c) Activities within and access to the tree protection zones are restricted so that no soil, spoil, aggregate, supplies/materials and/or waste materials etc. are placed within the protection areas, and no vehicles and equipment may pass within these zones. d) The trunks or limbs of retained trees may not be used to affix signs, lights, cables or any other device. e) Signs stating TREE PROTECTION AREA NO ENTRY should be placed on the tree protection fence at a suitable frequency. e) If encroachment into the tree protection zone is required for any other reason, it should be authorized in advance by the project arborist. Special measures may need to be implemented to allow access, and some activities will not be allowed. f) Removal of the tree protection fence and/or encroachment into the tree protection areas may constitute an offence under city bylaw provisions, and also may be subject to fines, penalties and/or delays in the project. ARBORTECH CONSULTING LTD PAGE 3 OF 5 APRIL 28, 2011 ARBORTECH CONSULTING LTD PAGE 4 OF 5 APRIL 28, 2011 app.g-6

7 SITE 1: PROPOSED CHILD CARE CENTRE CONCLUSIONS A total of seventeen bylaw trees were considered in this assessment. Nine trees have been determined to be unsuitable for retention and are proposed to be removed. Eight trees were deemed to be viable for retention and are proposed to be retained and protected in the proposed development. Two trees require remedial pruning of selected stems to maintain their future structural integrity. Tree replacement will be determined by the city. Please note: The final design details are subject to review and may impact on the safe retention of the selected trees. Thank you for choosing Arbortech for your tree assessment needs. If you require any further information, please call me directly at to discuss. Regards, Guy Exley, Consulting Arborist ISA Certified Arborist #PN-7184A Enclosures; Tree Inventory List Tree Retention Drawing ARBORTECH CONSULTING LTD PAGE 5 OF 5 APRIL 28, 2011 app.g-7

8 ACL SITE 1: TREE LIST FILE: ACL SITE 1: TREE LIST FILE: LEGEND: TAG #: DBH: SPECIES: CONDITION: NOTES: RET VALUE: ACTION: TREATMENTS: denotes the tag affixed to the tree for identification purposes. Locations are provided by the project surveyor. denotes the diameter of the trunk, measured in cm at 1.4 m above grade or as per arboricultural standards. as noted health/structure rating; High Risk = deemed hazardous by CTRA methods. Very Poor = dead, severe defects, severe decline. Poor = low vigour, noted defects, decline. Normal = fair to good condition considering its growing environment. pertinent details of notable defects that were observed. ratings are; Nil = not viable to retain. Low = limited useful remaining life. Marginal = conditional retention depending on site and project factors. Full = fully viable for retention. the designation to Remove or Retain the tree in the management of the existing landscape or in the development planned for the property. additional measures related to retaining the tree. Details of the treatments are provided in the accompanying arborist report. Tag # Dbh Species Condition Notes Retention Value Action London plane Normal Minor surface root damage Full Retain London plane Normal Minor dead branches throughout crown Full Retain London plane Normal Minor dead branches throughout crown. Twinstems Full Retain at 6m height with east stem distorted at union (at flare) London plane Poor Twin-stems at 2m height with included bark north side and soil pocket in union. Poor branch architecture. Limited future potential. Other Treatments Marginal Interim Retain Prune: Subordinate prune the noted eastern stem London plane Normal No significant defects Full Remove for London plane Normal No significant defects Full Remove for Norway spruce Poor Lower crown marms developing with heavy cone crop beginning to breakout branches. Limited future potential Norway spruce Poor Heavy cone crop beginning to breakout branches. Yellowing foliage indicating poor health. Limited future potential Norway spruce Normal Heavy cone crop likely to start breaking out branches. Marginal Marginal Full Remove for Remove for Remove for Norway spruce Normal As for 229 Full Remove for Norway spruce Normal As for 229 Full Remove for London plane Normal Surface root damage Full Retain London plane Poor Lateral stem at 2.5m height east side with narrow and weak union to main stem. Minor Marginal Interim Retain Prune: Subordinate prune the noted eastern stem surface root damage London plane Normal Surface root damage Full Retain London plane Normal Surface root damage Full Retain London plane Normal Extensive surface root damage Full Remove for London plane Normal Surface root damage Full Remove for SITE 1: CHILDREN'S - WOMEN'S HEALTH CENTRE 1 APRIL 26, 2011 SITE 1: CHILDREN'S - WOMEN'S HEALTH CENTRE 2 APRIL 26, 2011 app.g-8

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10 SITE 2: PROPOSED FAMILY-STAY AND RESPITE HOUSE April 28, 2011 Attn.: Kari Madsen Dysarchitecture Burrard Street Vancouver, BC V6J 3G7 cc: ACL File: Project Ref: Site 2: Proposed Family-Stay and Respite House Children s and Women s Hospital, 4500 Oak Street, Vancouver Re: Preliminary Tree Retention Assessment Report Dear Kari, Arbortech Consulting Ltd has been retained to undertake a detailed study of the existing trees located on or within close proximity to the above noted site to determine their current condition and to make preservation and protection recommendations in context to the proposed land use changes. Staff from this office visited the site on April 26, 2011 to inspect the trees. The tree location and topographic plan as well as the approximate area of the proposed footprint for the project have been provided for our use in completing this report. The final design and layout details may impact on the safe retention of selected trees. Outstanding details are but are not limited to; final building footprint, unknown geo-technical conditions, final grades, unknown above and below ground servicing locations, hard and soft landscaping etc. Note that if any changes to the tree retention scheme, or if any encroachments into the protection areas are deemed to be necessary for purposes, that they are subject to approvals in advance by the city and/or the project arborist. The tree condition data and the preliminary tree retention recommendations are compiled herein and on the enclosures. PRELIMINARY RETENTION REVIEW All bylaw trees located on or within close proximity to the development site have been assessed using Visual Tree Assessment (VTA) procedures. Trees have also been tagged with a serial number as referenced in this report, on the attached tree retention plan, and for future reference within the design, approval and phases of the project. eastern property line there are a linear group of 3 young Ash and 4 Honey locust City street trees. Within the car park area and southern boundary of the subject site, there are 6 new Red oaks and 2 Austrian pines planted circa 1 to 2 years ago. The majority of these trees are suffering transplant shock and are in a poor condition with three trees in mortal decline. Please note; the boundary trees south west of tree # s 193 and 194 detailed on the supplied topographical drawing have been historically removed. A photographic record of the subject trees is on file. The trees are detailed as follows. The subject trees have been compiled in a Tree Inventory List where we present the tree specific data and observations. In addition, we have rated the condition of the trees based on both health and structure factors that guide us in determining the value and viability of retaining the trees. The Preliminary Tree Retention Drawing shows the location and proposed treatment of the subject trees. Both documents are included as attachments to this report and should be referenced by the reader for applicable details. On this site, the proposed development and consists of a Family-Stay and Respite House and associated hard and soft landscaping. The assessed trees have been assigned a rating as to their overall condition considering the current health and the current structural integrity of the tree. These trees were rated based on their current condition in relation to their value and viability for retention for consideration in the proposed land use. The viability ratings are summarized as follows. Table 1. TREE RETENTION VIABILITY SUMMARY, ON-SITE BYLAW SIZE TREES ONLY 3 Non-Viable Trees: Trees that are suffering from advanced health decline or significant structural defects that make them low value and viability for retention and/or would be considered high risk trees using CTRA methods considering the future land uses. These trees are also not considered viable for retention. 3 Marginal Trees: Trees that have structural defects or health concerns that are restorable with reasonable and practical treatments, and would be expected to survive impacts. The preservation of these marginal rated trees would be conditional to detailed review as well as contingencies for special measures. 16 Viable Trees: Trees that have no overt and significant defects or health issues, and that are well suited for retention. In general terms, the existing trees located on this site consist of mixture of deciduous and conifer species that form part of the original landscape tree planting associated with the hospital site. The subject trees consist of 10 London plane, 5 Red oak, 3 Serbian spruce, 2 Western redcedar, 1 Douglas fir and 1 Blue Atlas cedar. In particular, the London plane trees form a linear group to the internal access road and the five Red oaks form a feature group to the eastern property line with Heather Street. To the SUITE CHATHAM STREET RICHMOND BC V7E 2Z3 P F E trees@arbortech.bc.ca ARBORTECH CONSULTING LTD PAGE 2 OF 5 APRIL 28, 2011 app.g-10

11 SITE 2: PROPOSED FAMILY-STAY AND RESPITE HOUSE SITE 2: PROPOSED FAMILY-STAY AND RESPITE HOUSE RECOMMENDATIONS In context to the proposed land use changes, the existing trees are recommended to be treated as follows: Retain and Protect 15 trees Tag # s: 196, 197, 198, 199, 200, 205, 206, 207, 208, 209, 210, 211, 212, 213 and 214 These trees form feature groups to the west and north boundary lines of the subject site. These groups provide softening and screening to the proposed building and degree of separation form the associated hospital buildings to the north and west of the site. Pursuant to the tree protection guidelines noted below and on the attached drawing, these trees could be preserved within the project. Protection Details: a) Trees # s 205, 206, 207, 208, 209, 210, 211, 212, 213 and 214: The existing asphalt surfacing within the root protection zones of the London plane trees can be retained as ground protection during works and removed under arboricultural supervision after the main phase is complete. However, if removed prior to commencement of site works, the grade is to be reinstated with quality top soil and the protective fencing erected 6m radii from the tree bases. b) Tree # s 196, 197, 198, 199 and 200: Any proposed re-grading to the south of the Red oak group will require review of the final design details and arboricultural supervision during any approved works to minimise damage and encroachment into the root zones. Remove 5 Trees for Construction Tag # s: 193, 194, 195, 203 and 204 Of the 5 trees, tree# 195 is categorised as Nil retention viability due to pre-existing defects. The remaining four trees are fully viable but of an age and size where transplanting is not a practical or cost effective option. Further these trees are not the principal landscape features within the site and therefore can be easily mitigated with new planting. Remove 3 Nil Retention Value Trees Tag # s: 195, 201 and 202 All trees with Nil retention value should be removed due to their pre-existing defects and other condition factors that make them very low value and/or otherwise not worthy for protection in this project. Remove 6 under bylaw size Red oaks These 6 newly planted trees are located within the small planters within the existing car park area. The majority of these trees are in poor health and condition as a result of transplant shock. Given this, transplanting to new locations within the site is not recommended. Off-Site City Trees Trees: A, B, C, D, E, F and G ARBORTECH CONSULTING LTD PAGE 3 OF 5 APRIL 28, 2011 These trees are at distance from the proposed building footprint not to have or be influenced by the works and therefore no protection measures are required. Retained Trees that require Pruning Tag # s: 205, 206, 207, 208, 209, 210, 211, 212, 213 and 214 These trees require remedial pruning to give clearance over internal roads and lamp columns or to maintain their future structural integrity. See Tree List Other Treatments for details. Tree Protection Fencing. Tree protection fences must be erected as shown on the tree retention plan and restriction implemented as per the guidelines below to maintain compliance with the City of Vancouver Tree Protection Bylaw No It is recognized that certain unpredictable conflicts may arise that could interfere with the safe retention of the selected trees. Examples include but are not limited to; unknown geo-technical conditions, unknown underground servicing locations, etc. Note that if any changes to the tree retention scheme, or if any encroachments into the protection areas are deemed to be necessary for purposes, that they are subject to approvals in advance by the city and/or the project arborist. Tree Replacement. City requirements will dictate the required quantity of replacement trees for this project. Among other factors, the size and land use of the property as well as the presence of retained trees must be considered in determining the available space for planting. Those determinations will be subject to direction and/or approval by the city. Specifications for replacement trees will be provided by the project landscape consultant. Permitting. The removal of any bylaw trees will require that a permit is issued by the city. Application is made concurrently with the re-zoning and/or building permit application. Tree Inspection Regime In respect to good arboricultural management and in context with the site usage, it is recommended that the retained tree are inspected post development impact and circa every 2 years thereafter to monitor health and structural integrity. In particular tree # s 199, 206 and 207 have noted structural defects that require inspection and monitoring. TREE PROTECTION GUIDELINES 1. Tree Protection: a) All retained trees must be protected to meet Municipal and/or Arbortech specifications. The minimum standard for fence type that is required is detailed above. b) The tree protection fencing should be inspected and approved by the municipality and/or the project arborist prior to any demolition, site preparation ARBORTECH CONSULTING LTD PAGE 4 OF 5 APRIL 28, 2011 app.g-11

12 SITE 2: PROPOSED FAMILY-STAY AND RESPITE HOUSE or work commencing. c) Activities within and access to the tree protection zones are restricted so that no soil, spoil, aggregate, supplies/materials and/or waste materials etc. are placed within the protection areas, and no vehicles and equipment may pass within these zones. d) The trunks or limbs of retained trees may not be used to affix signs, lights, cables or any other device. e) Signs stating TREE PROTECTION AREA NO ENTRY should be placed on the tree protection fence at a suitable frequency. e) If encroachment into the tree protection zone is required for any other reason, it should be authorized in advance by the project arborist. Special measures may need to be implemented to allow access, and some activities will not be allowed. f) Removal of the tree protection fence and/or encroachment into the tree protection areas may constitute an offence under city bylaw provisions, and also may be subject to fines, penalties and/or delays in the project. CONCLUSIONS A total of twenty two on-site bylaw trees and eight under bylaw size, and seven off-site City trees were considered in this assessment. Seven trees have been determined to be unsuitable for retention and are proposed to be removed. Fifteen trees were deemed to be viable for retention and are proposed to be retained and protected in the proposed development. Ten trees require remedial pruning to give clearance to site infrastructure and/or to maintain their future structural integrity. Tree replacement will be determined by the city. Please note: The final design details are subject to review and may impact on the safe retention of the selected trees. Thank you for choosing Arbortech for your tree assessment needs. If you require any further information, please call me directly at to discuss. Regards, Guy Exley, Consulting Arborist ISA Certified Arborist #PN-7184A Enclosures; Tree Inventory List, Tree Retention Drawing ARBORTECH CONSULTING LTD PAGE 5 OF 5 APRIL 28, 2011 app.g-12

13 ACL SITE 2: TREE LIST FILE: ACL SITE 2: TREE LIST FILE: LEGEND: TAG #: DBH: SPECIES: CONDITION: NOTES: RET VALUE: ACTION: TREATMENTS: denotes the tag affixed to the tree for identification purposes. Locations are provided by the project surveyor. denotes the diameter of the trunk, measured in cm at 1.4 m above grade or as per arboricultural standards. as noted health/structure rating; High Risk = deemed hazardous by CTRA methods. Very Poor = dead, severe defects, severe decline. Poor = low vigour, noted defects, decline. Normal = fair to good condition considering its growing environment. pertinent details of notable defects that were observed. ratings are; Nil = not viable to retain. Low = limited useful remaining life. Marginal = conditional retention depending on site and project factors. Full = fully viable for retention. the designation to Remove or Retain the tree in the management of the existing landscape or in the development planned for the property. additional measures related to retaining the tree. Details of the treatments are provided in the accompanying arborist report. Tag # Dbh Species Condition Notes Retention Action Other Treatments Value Serbian spruce Normal No significant defects Full Remove for Serbian spruce Normal Heavily ivy clad main stem Full Remove for Prune: Sever ivy Blue atlas cedar Very Poor Historically topped at 2m height resulting large Nil Remove marms and poor stem architecture. Sparse foliage typical of low vigour Red oak Normal Tree #'s 73 to 86 form a group with merged Full Retain canopies. As a result all trees have developed varying degrees of crown asymmetry typical of woodland 'edge' trees. Minor surface root damage Red oak Normal As for 196 Full Retain Red oak Normal As for 196 Full Retain Red oak Poor As for 196 plus major root girdling and internal stem seam from ground level to 2m height south Marginal Interim Retain Inspection regime required to monitor health and structure side Red oak Normal As for 196 Full Retain Western redcedar Poor Twin-stems at 9m height with narrow and weak union. Permanently impaired tree that will be open to new wind pressures with the removal of adjacent tree # Western redcedar Very Poor Twin-stems at 7m height with narrow and weak union. Large marms have developed due to historic lost leader. Permanently impaired tree. Nil Nil Remove Remove Serbian spruce Normal No significant defects Full Remove for Douglas fir Normal No significant defects Full Remove for London plane Normal Tree #'s 205 to 214 form a linear group with low branching over access roads and parking bays. Full Retain Prune: Crown lift London plane Poor Significant main stem distortion at 5m height. Limited future potential. Marginal Interim Retain Prune: Crown lift and consider regime of crown reduction if retained in the long-term London plane Poor 10% die-back of main leader. Marginal Interim Retain Prune: Crown lift and clean. Monitor health London plane Normal Dead branches throughout crown Full Retain Prune: Crown lift and clean London plane Normal No significant defects Full Retain Prune: Crown lift London plane Normal No significant defects Full Retain Prune: Crown lift London plane Normal No significant defects Full Retain Prune: Crown lift London plane Normal No significant defects Full Retain Prune: Crown lift London plane Normal No significant defects Full Retain Prune: Crown lift London plane Normal Canopy encroaching street lamp. Large old branch scar at 10m height with good wound wood development. Full Retain Prune: Crown lift and prune back to clear lamp column. SITE 2: CHILDREN'S - WOMEN'S HEALTH CENTRE 1 APRIL 26, 2011 SITE 2: CHILDREN'S - WOMEN'S HEALTH CENTRE 2 APRIL 26, 2011 app.g-13

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