JOSHUA CREEK (BRESSA AND DUNOAK LANDS)

Transcription

1 JOSHUA CREEK (BRESSA AND DUNOAK LANDS) i First Submission: February 3, 2016 Prepared for: Mattamy Development Corp. Prepared by: NAK Design Strategies

2 1 JOSHUA CREEK (BRESSA AND DUNOAK LANDS)

3 SECTION 1: INTRODUCTION 1.1 PURPOSE OF THE ANALYSIS The Joshua Creek (Bressa and Dunoak Lands) Tree Canopy Coverage Analysis represents a general assessment of the projected tree canopy coverage for these lands within North Oakville. The community will be comprised of Neighbourhood Centre Areas, Dundas Urban Core Areas along the south perimeter, single-detached and semi-detached residential dwellings, a Neighbourhood Park, several Village Squares, stormwater management ponds and an Elementary School. This analysis quantifies, at a conceptual level, how these lands may contribute to the tree canopy coverage, and will estimate the projected coverage for streets and the proposed parks based, in part, on standard calculation methods outlined in the North Oakville Urban Forest Strategic Management Plan (NOUFSMP - Natural Resource Solutions Inc. & Dillon Consulting Limited, November 2011). It will also address potential measures within the Joshua Creek (Bressa and Dunoak) lands that will help meet the criteria established within the NOUFSMP for achieving the Town of Oakville s long term objective of a 40% urban forest canopy cover, including criteria related to soil volume, tree health and tree spacing. This analysis will be informed by the current conceptual Draft Plan, with future driveway and utility constraints considered as an average based on similarly developed residential streetscapes. dufferin county wellington county 124 JOSHUA CREEK (BRESSA AND DUNOAK LANDS) SITE NORTH OAKVILLE 125 orangeville 7 peel regional 107 TREMAINE RD. 410 brampton REGIONAL ROAD 25 HIGHWAY york regional NEYAGAWA BOULEVARD BURNHAMTHORPE ROAD EAST SIXTH LINE DUNDAS STREET WEST 404 toronto region pearson international airport TRAFALGAR ROAD toronto NINTH LINE markham 2 durham regiona 1.2 DEVELOPMENT SITE CONTEXT The Joshua Creek (Bressa and Dunoak Lands) study area consists of a combined acres (89.2 ha.) and is located within the North Oakville Secondary Plan Area (also referred to as North Oakville East) in the Town of Oakville. North Oakville East is bounded by Dundas Street to the south, Highway 407 to the north, Tremaine Road to the west and Ninth Line to the east. The development site for Joshua Creek (Bressa and Dunoak Lands) is bounded to the north by future development extending to Old Burnhamthorpe Road and the south by Dundas Street East. The subject area is divided into two land parcels, namely Bressa and Dunoak, with a third, Dryland, forming a separate phase and not included in this analysis. waterloo regional 24 Guelph brantford 253 hamilton division halton regional milton 407 hamilton 10 mississauga north oakville burlington hamilton international airport LEGEND niagara regional north oakville development area major centre major arterial arterial border canada-usa 406 border st. catharines Fig. 1.2a - Regional Context Map and Joshua Creek (Bressa and Dunoak Lands) Development Area

4 Fig. 1.2b - Joshua Creek (Bressa and Dunoak Lands) Development Areas. 2 Fig. 1.2c - Joshua Creek (Bressa and Dunoak Lands) Land Use Plan. JOSHUA CREEK (BRESSA AND DUNOAK LANDS)

5 1.3 NORTH OAKVILLE URBAN FOREST STRATEGIC MANAGEMENT PLAN (NOUFSMP) The North Oakville Urban Forest Strategic Management Plan is a high level strategy and planning study prepared to provide the Town of Oakville with recommendations and guidelines for achieving a sustainable, healthy urban forest for the North Oakville development lands. This strategy is an extension of the Town s long term vision to achieve its 40% tree canopy coverage target. North Oakville comprises approximately 4,000 hectares of land, with roughly 1,600 hectares of tree canopy coverage required to achieve the 40% target. The designated Natural Heritage System (NHS), which includes native forests, cultural woodlands, shrublands and agricultural hedgerows, accounts for approximately 1,200 hectares of North Oakville s land area, making it a significant contributor to achieving the 40% target. The remaining approximately 400 hectares of coverage is expected to be achieved through land development (residential, employment/industrial, institutional and commercial), including streetscapes, parks, buffers, cemeteries, stormwater management facilities, parking lots, etc. The following is a brief summary of some of the targets, recommendations and measuring criteria described in the NOUFSMP that are pertinent to assessing the ultimate long term tree canopy coverage within the Joshua Creek (Bressa and Dunoak Lands) study area Tree Classification and Sizing The canopy coverage plan shall comply with the following guidelines - ornamental trees (3-6m spread) = 15 sq.m and shown as 3m dia. small stature trees (7-8m spread) = 45 sq.m and shown as 7m dia. medium stature trees (9-11m spread) = 80 sq.m and shown as 10m dia. large stature trees (12+m spread) = 115 sq.m and shown as 12m dia Projected Park Canopy Coverage Village Square - 77% Neighbourhood Park - 57% Community Park - 66% Notwithstanding the above percentages, a more realistic standard of 50% may be used for estimating purposes, considering potential site and park facility constraints that may limit the plantable area available for tree planting. Canopy coverage reflects an estimate of the proportion of the ground area that is covered by tree and shrub crowns, expressed as a percentage value. Where canopies merge or overlap, the combined area contributes to the coverage requirement, as opposed to including the canopy area of each overlapping tree Soil Volumes A minimum of 15 cu.m of soil volume per tree is required (based on a maximum 900mm depth of cover). Notwithstanding the minimum soil volume, the following represents the recommended volumes per tree - ornamental trees (6m spread and less) = min. 10 cu.m small stature trees (7-8m spread) = min. 15 cu.m medium stature trees (9-11m spread) = min. 30 cu.m large stature trees (12m spread and greater) = min. 45 cu.m Projected Street Tree Canopy Coverage (Residential) As a general proposed standard, the NOUFSMP recommends achieving a 20% street tree canopy coverage for residential developments. However, it is noted that trees will not reach their full genetic size potential within most streetscape environments. Furthermore, opportunities for street tree planting may be affected by the objective of achieving a more dense, compact and transit-oriented environment, as part of applying New Urbanism principles to planned North Oakville development. 3

6 SECTION 2: JOSHUA CREEK (BRESSA AND DUNOAK LANDS) TREE CANOPY COVERAGE Within the Joshua Creek (Bressa and Dunoak Lands) study area, the canopy coverage contribution will be achieved through the proposed streetscape treatment, the partial Neighbourhood Park and the 4 Village Squares that are situated throughout the 2 land areas. Although not measured specifically in this analysis, a secondary contribution may be considered through front and rear yard landscape treatments. This can account for approximately 1-2% coverage and is typically derived from smaller stature trees. 2.1 STREET TREE CANOPY COVERAGE The street tree canopy coverage calculation for the Joshua Creek (Bressa and Dunoak Lands) study area is a preliminary estimate based on a conceptual land use plan. It corresponds with the proposed road hierarchy and assumes all trees to be planted within grass boulevards, with the possible exception of potential urban hardscape boulevard treatments for streets located within Dundas Urban Core and Neighbourhood Centre Areas. Considering the type of residential development intended for the community, it is not expected that engineered soils (e.g. structural soils or cell support structures) will be utilized. Street trees have been indicated, on average, at approximately one tree per lot. Most street trees in this assessment have been designated as small stature, until such time a more comprehensive streetscape plan can be undertaken as part of a detailed landscape plan review process. Medium stature trees have been situated along Dundas Street East and the collector road network, where greater boulevard widths are anticipated, along with reduced driveway interruptions. The selection of smaller stature trees are largely due to the limited soil volumes characteristic of the standard street right-of-way boulevards proposed within North Oakville. Even when integrating measures such as root breakout zones beneath the sidewalks, achieving 30 cubic metres of soil volume is not likely on any consistent basis. Therefore, adhering to the recommended soil volumes from the NOUFSMP requires the selection of predominantly smaller stature street trees. This, in turn, results in an overall tree canopy coverage percentage that is lower than when using medium stature trees and short of the Town of Oakville s street tree target The preliminary tree canopy coverage results are as follows (refer to figure 2.1): Total Joshua Creek (Bressa and Dunoak Lands) Land Area - approx. 601,500 sq.m (not including the Neighbourhood Park portion, Village Squares, SWM ponds, Elementary School, NHS and associated buffers and open spaces - 290,500 sq.m.). Total Joshua Creek (Bressa and Dunoak Lands) Street Tree Canopy Coverage Area - approx. 85,500 sq.m (not including the Neighbourhood Park portion, Village Squares, SWM ponds, Elementary School, NHS and associated buffers and open spaces) Joshua Creek (Bressa and Dunoak Lands) Street Tree Canopy Coverage = 14.2% (85,500 / 601,500) 4 JOSHUA CREEK (BRESSA AND DUNOAK LANDS)

7 Figure Conceptual Street Tree Canopy Coverage Plan for Joshua Creek (Bressa and Dunoak Lands). 5

8 2.2 PARKS CANOPY COVERAGE The Joshua Creek (Bressa and Dunoak Lands) Neighbourhood Park and Village Squares tree canopy coverage calculation is a preliminary estimate based on proposed facility fit plans. These designs are currently conceptual and subject to potential modification as part of a detailed landscape design process. All tree sizes have been included in the design and assessment, including ornamental / coniferous, small stature, medium stature and large stature trees. The preliminary tree canopy coverage results are described in the following: Neighbourhood Park Portion Total Neighbourhood Park Area (portion within Bressa lands) - approx. 18,500 sq.m Total Neighboourhood Park Area Tree Canopy Coverage Area - approx. 3,000 sq.m Neighbourhood Park Tree Canopy Coverage = 16.2% (3,000 / 18,500) Evaluation of this result should consider that a substantial component of the Neighbourhood Park portion is comprised of two athletic fields, with the majority of trees to be located in the portion of the park that sits outside the Bressa lands. Figure Conceptual Neighbourhood Park Tree Canopy Coverage Plan. 6 JOSHUA CREEK (BRESSA AND DUNOAK LANDS)

9 2.2.2 Village Square Block 50 Total Village Square Block 50 Area - approx. 4,300 sq.m Total Village Square Block 50 Tree Canopy Coverage Area - approx. 2,500 sq.m Village Square Block 50 Tree Canopy Coverage = 58.1% (2,500 / 4,300) Village Square Block 51 Total Village Square Block 51 Area - approx. 4,000 sq.m Total Village Square Block 51 Tree Canopy Coverage Area - approx. 2,800 sq.m Village Square Block 51 Tree Canopy Coverage = 58.3% (2,800 / 4,000) Figure Conceptual Village Square Block 50 Tree Canopy Coverage Plan. Figure Conceptual Village Square Block 51 Tree Canopy Coverage Plan. 7

10 2.2.4 Village Square Block 3 Total Village Square Block 53 Area - approx. 2,700 sq.m Total Village Square Block 53 Tree Canopy Coverage Area - approx. 1,600 sq.m Village Square Block 53 Tree Canopy Coverage = 59.3% (1,600 / 2,700) Village Square Block 54 Total Village Square Block 54 Area - approx. 3,000 sq.m Total Village Square Block 54 Tree Canopy Coverage Area - approx. 1,900 sq.m Village Square Block 54 Tree Canopy Coverage = 63.3% (1,900 / 3,000) Figure Conceptual Village Square Block 53 Tree Canopy Coverage Plan. Figure Conceptual Village Square Block 54 Tree Canopy Coverage Plan. 8 JOSHUA CREEK (BRESSA AND DUNOAK LANDS)

11 2.3 CONCLUSION There are many factors that will contribute to the health and long term sustainability of the tree canopy within Joshua Creek (Bressa and Dunoak Lands) and the surrounding areas. In addition to maximizing tree planting oppotunities and protecting existing natural heritage features, resolving issues related to soil compaction, soil quality, soil volumes and tree species selection in an increasingly urban environment will be fundamental to reaching the overall 40% tree canopy coverage targeted for the Town of Oakville. These issues can be considered in a comprehensive depth during the detailed landscape design process. 9