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Ashbridges Bay Light Rail Vehicle (LRV) Maintenance and Storage Facility – Transit Project Assessment – Environmental Project Report stands up to 15 metres above the surrounding lands. Young trees and shrubs cover parts of the hill, but most of these 3. Existing Conditions appear to have been planted. A sign on the west part of the site indicates that at least part of the site was planted by Metro Works and Boy Scouts in 1995. This corresponds well with the size of many of the trees and shrubs. The study The following sub-sections provide a description of the existing conditions on the site, and where appropriate, the site is composed of young, culturally influenced vegetation communities, including: meadows, thickets, and deciduous surrounding lands. This section has been divided into the follow factors: plantations. Most of the site lies within a fenced in area that restricts access by the general public. Natural Environment The vegetation community names and codes have been adapted from the Ecological Land Classification (ELC) system Social Environment (Lee et al. 1998). While ELC is the standard method for describing vegetation in Ontario, it is not inclusive enough to Traffic and Transportation include all vegetation types, particularly culturally influenced ones such as those present in the subject site. The trees and shrubs are essentially all planted and therefore vegetation has not developed naturally. The site has not been The information documented in this section is also available in the following technical reports: mowed for the past several years, consequently grasses and forbs grown in adventively and most of the site is meadow. The vegetation types are mapped Figure 3-1 (Existing Vegetation Features Figure) and described below. Tree Inventory and Assessment Report (Arborist Report), February 2010; Subsurface Investigations TTC LRV Maintenance & Storage Facility: Lake Shore Boulevard East and CUM1 – Cultural Meadow Leslie Street, October 2009; Phase I Environmental Site Assessment and Contaminated Sites Screening Report, February 2010; The site is mostly covered with graminoid (grass-dominated) meadow vegetation that is largely co-dominated by Quack Phase II Environmental Site Assessment, March 2010; Grass (Agropyron repens), Kentucky Bluegrass (Poa pratensis), Red Fescue (Festuca rubra) and Smooth Brome Grass Cultural Heritage Resources Assessment, October 2009 (revised April and July 2010); (Bromus inermis). A variety of broad-leaved forbs are represented. The most abundant species include Canada Stage 1 Archaeological Assessment Report, October 2009 (revised July 2010); Thistle (Cirsium arvense), Cow Vetch (Vicia cracca), Chicory (Cichorium intybus), Birdsfoot Trefoil (Lotus corniculatus), Traffic Impact Study, September 2010; Heath Aster (Aster ericoides) and Wild Carrot (Daucus carota). Noise & Vibration Environmental Assessment Report, September 2010; Stormwater Management Report, August 2010; CUP1-4 – Carolina Poplar Deciduous Plantation Air Quality Assessment Report, February 2010; and Natural Heritage Impact Study, August 2010. Three rows of Carolina Poplar (Populus X canadense) have been planted along the western portion of the site, parallel to Leslie Street and just east of the pedestrian sidewalk. The trees are 8 to 10 metres tall with a diameter at breast height (dbh) of 10-15 centimetres. A few Green Ash (Fraxinus pennsylvannica) and Bur Oak (Quercus macrocarpa) are mixed in 3.1 Natural Environment among the poplars. Additional ornamental street trees have been planted along Lake Shore Boulevard including Ginkgo (Ginkgo biloba), Green Ash, Silver Maple (Acer saccharinum) and Kentucky Coffee-tree (Gymnocarpus dioica) 3.1.1 Terrestrial and Wildlife Natural Heritage CUP1-4a – Eastern Cottonwood Deciduous Plantation 3.1.1.1 Methodology Several sources were used to assess both the significant species and the natural heritage features within the study Stands of young Eastern Cottonwood (Populus deltoides) approximately 12 metres tall are situated on the north and area, as well areas 2 to 5 kilometres away from the specific site. These sources included: south edges of the flat-topped hill. The trees range from 10-25 centimetres dbh. Occasional Staghorn Sumacs and Manitoba Maple saplings occur below the canopy, while ground layer is dominated by Late Goldenrod (Solidago Topographic mapping of the site; altissima) and Smooth Brome. Natural Heritage Information Centre (NHIC), Ontario Ministry of Natural Resources for species risk information and vegetation communities rankings; CUS1 – Exotic Cultural Savannah Ontario Ministry of Natural Resources wetlands, Areas of Natural and Scientific Interest (ANSI‟s), fisheries and aquatic habitat information; Planted ornamental trees are present in two groups: along the south part, just north of the treatment plant parking lot, Natural Resources Values Information System (NRVIS) layer data; and and outside of the fence in the northeast corner. The trees are now mostly in the range of 3 to 8 metres tall and occupy A Tree Inventory and Assessment made using accepted standard arboriculture techniques as outlined in about 25% cover simulating savannah structure of meadow among scattered trees. Tree cover in the south portion the International Society of Arboriculture (ISA) Guide for Plant Appraisal, 9th Edition (2000). include mainly: Norway Maple (Acer platanoides) and Austrian Pine (Pinus nigra), but a number of other species are also present including Honey Locust (Gleditsia triacanthos), Catalpa (Catalpa sp.), Horse-chestnut (Aesculus A site investigation was conducted on October 20, 2009 to document existing conditions such as terrain and vegetation. hippocastanum) and White Spruce (Picea glauca). Tree makeup in the northeast area is largely Norway Maple, Silver Maple (Acer saccharinum), Black Alder (Alnus glutinosa) and Japanese Tree Lilac (Syrica reticulata). Meadow Vegetation Conditions vegetation as described in CUM1 (above) surrounds the trees. The proposed project site consists of abandoned industrial land located in a heavily industrialized area of Toronto. As CUT1-1 – Staghorn Sumac Cultural Thicket such, it has a history of intensive land use and therefore is very disturbed. Most of the site lies within a fenced-in area that restricts access by the general public. The subject property has a long history of soil importation and filling and therefore it Staghorn Sumac (Rhus typhina) forms a linear thicket along the western crest of the flat-topped hill. These were likely is very disturbed. A considerable amount of fill has been brought to the site, and graded to form a low flat topped hill that planted but are spreading outward. Some Manitoba Maple saplings are growing among the thicket. 19 Ashbridges Bay Light Rail Vehicle (LRV) Maintenance and Storage Facility – Transit Project Assessment – Environmental Project Report CUT1-A – Sandbar Willow Cultural Thicket A dense thicket of mostly Sandbar Willow (Salix exigua) 2-3 metres tall occurs on the eastern upper portion of the berm. A number of Manitoba Maple (Acer negundo) saplings up to 6 metres tall are scattered among this thicket. MAS2-1 Cattail Mineral Shallow Marsh A small unit of marsh containing both Broad-leaved Cattail (Typha latifolia) and Narrow-leaved Cattails (Typha angustifolia) occurs in a ditch between two patches of Common Reed marsh. Some Purple Loosestrife (Lythrum salicaria) and Spike-rush (Eleocharis erythropoda) is also present. MAM1-12 – Common Reed Mineral Meadow Marsh A ditch lies along the northern fringe of the site. Common Reed (Phragmites communis) forms two robust patches of marsh along the ditch,). Common Reed is a highly invasive grass that spreads by both seed and rhizomes. It is expanding beyond the confines of the ditch. In summary the site contains disturbed and imported soils that have regenerated to field vegetation. The majority of the trees and shrubs which occur on site appear to have been planted, with some natural regeneration of Manitoba Maple and American Elm (Ulmus americana). Consequently the vegetation on site cannot be considered natural. Few of the plant species found on site are locally indigenous. The field species are also predominantly non-native. None of the identified communities are listed as “Rare” within Ontario according to the provincial Natural Heritage Information Centre (NHIC). In addition, a Tree Inventory and Assessment was conducted for the proposed Ashbridges Bay Fleet LRV maintenance and storage facility site. The report documented 238 trees or groups of trees on the site, their size and condition (excellent, fair or poor). The total number of individual trees is estimated to be near 370. Of these trees, seven were found to have a diameter breast height (dbh) measurement of 30 centimetres or higher. The tree inventory list is contained in Drawing No. TI-1 of Technical Report # 1 – Tree Inventory and Assessment Report, February 2010. Flora Apart from planted species trees and shrubs, a total of 87 plant species were identified in the study site through field investigations of which 71 species are non-native, representing 81.6 % of the total. The complete list of plant species in contained in Technical Report # 11 – Natural Heritage Impact Study, July 2010. This is an exceptionally high percentage and reflects the early successional nature of the site, the highly disturbed fill soils (lacking any native parent soils) and the seed source from surrounding disturbed urban lands. Any site where the floral component is more than one third is