Review of Environmental Issues for the Development of the Grafton Lake Lands, Bowen Island, BC
admin
- Amphibians, Biological invasions, Birds, Conservation & Protected Areas, Ecology, Ecosystems, Environmental impact statements, Environmental planning, Freshwater ecology, Hydrology, Mammals, Plants, Riparian ecology, Species Biodiversity, Water quality, Water Resources, Watershed management, Wetland ecology
Basics
Title
Review of Environmental Issues for the Development of the Grafton Lake Lands, Bowen Island, BC
Description
AI-generated: This report, commissioned by the Bowen Island Conservancy and prepared by Raincoast Applied Ecology, identifies and evaluates potential environmental issues associated with the proposed development of the Grafton Lake Lands in central Bowen Island, BC. Based on a review of existing literature and approximately four days of field reconnaissance in spring 2015, the report examines five key environmental issues: changes to hydrology and water quality, loss or disturbance to sensitive ecosystems, loss or disturbance to species and ecological communities at risk, habitat fragmentation and loss of landscape connectivity, and disturbance from increased recreation use. The study area encompasses 158 hectares of private land (the Rennison Lands, owned by Primex Investments Limited) centred on Grafton Lake, which supplies drinking water to approximately 48% of Bowen Island residents through the Cove Bay Water System. The proposed concept plan would construct approximately 100 residential dwellings, a wellness institute, and a farming area on 36% of the property, while protecting 57% as a nature preserve. The report characterizes the ecological values of the area -- including regionally significant wetlands, riparian ecosystems, sensitive rock outcrops, mature forests, and confirmed species at risk -- and outlines outstanding information gaps requiring further assessment before development proceeds.
Date
January 1, 2015
Creator Organization
Raincoast Applied Ecology
Authors
Claudia Schaefer | Nick Page
Document Type
Report
Subject Area
Species Biodiversity > Amphibians | Ecology > Biological invasions | Species Biodiversity > Birds | Conservation & Protected Areas | Ecology | Ecosystems | Policy & Governance > Environmental impact statements | Policy & Governance > Environmental planning | Ecosystems > Freshwater ecology | Water Resources > Hydrology | Species Biodiversity > Mammals | Species Biodiversity > Plants | Ecosystems > Riparian ecology | Species Biodiversity | Water Resources > Water quality | Water Resources | Water Resources > Watershed management | Ecosystems > Wetland ecology
Metadata
Keywords
Grafton Lake
|Bowen Island
|environmental review
|development
|ecological issues
|hydrology
|water quality
|sensitive ecosystems
|wetlands
|riparian
|species at risk
|habitat fragmentation
|landscape connectivity
|recreation
|Cove Bay Water System
|drinking water
|Bowen Island Conservancy
|Raincoast Applied Ecology
|nature preserve
|Bowen Island Ecological Reserve
|Mt Gardner
|Mt Apodaca
|Terminal Creek
|Killarney Creek
|Bowen Brook
|Raven Brook
|Rennison Creek
|Warbler Creek
|Northern Red-legged Frog
|Coastal Cutthroat Trout
|Western Screech Owl
|common cattail marsh
|Sensitive Ecosystem Inventory
|Agricultural Land Reserve
|Primex Investments
|Rennison Lands
|rezoning
|greenway
|forested swamp
|velvet-leaf blueberry
|Pacific crabapple-Sitka spruce swamp
Time Period
2015 (field surveys spring 2015; concept plan March 2015 draft)
Relationship - hasPart
Document ID
2605072013
Document ID
2605072013
Document ID
2605072013
Document ID
2605072013
Document ID
2605072013
Document ID
2605072013
Document Filename
schaefer-page-grafton-lakel-lands-environmental-review-2015-final_2605072013.pdf
Storage Location
analysis/other-sources/
Key Findings
AI-generated: The report identifies five key environmental findings. (1) Hydrology and water quality: Grafton Lake supplies drinking water to ~48% of island residents; development in the watershed, particularly in Development Node 1 south of Grafton Road, poses risks of increased sediment, nutrient loading (especially phosphorus), and microbiological contamination; climate change and population growth are considered greater long-term threats to lake hydrology than the proposed development itself. (2) Sensitive ecosystems: the study area contains regionally significant wetlands (approximately 12 ha surrounding the 15 ha lake), riparian areas, cliffs and rock outcrops, and mature forests; the majority are located within or near the proposed nature preserve; invasive species (e.g. English holly) are already present. (3) Species and ecological communities at risk: confirmed species include Northern Red-legged Frog and Coastal Cutthroat Trout; common cattail marsh (blue-listed) is present; mature forests may harbour red- and blue-listed ecological communities; no comprehensive species surveys have been conducted. (4) Habitat fragmentation: the Grafton Lake Lands are a critical ecological corridor linking Mt Gardner and Mt Apodaca; Development Nodes 2, 3, and 4 are expected to have minor connectivity impacts, while Development Node 1 requires more detailed assessment; greenways should be 50-100+ m wide to be effective. (5) Recreation impacts: increased trail use, swimming, and boating will raise risks of sediment input, wildlife disturbance, and drinking water contamination; a ring trail around the lake would eliminate currently undisturbed wildlife refugia.
Methodology
Review based on existing information sources and approximately 4 days of reconnaissance field surveys in spring 2015. Detailed field surveys and wildlife inventories were not undertaken. Sensitive ecosystem mapping used the existing Bowen-Gambier Sensitive Ecosystem Inventory (SEI) data, updated with reclassification guidance from the BC Conservation Data Centre and lead author's collaboration with CDC staff. Species at risk assessment relied on BCCDC lists and habitat conditions rather than systematic surveys. GIS mapping by J. Dunster provided data on forest cover, trails, watercourses, and wetlands. Review also drew on Whitehead Environmental Consultants environmental overview (2015) and GIS data.
Map Descriptions
Page 28: Aerial satellite map of Bowen Island showing the location of the Grafton Lake Lands (red rectangle outline) in the central portion of the island. Yellow line indicates the Grafton-Killarney watershed boundary; orange line indicates a secondary watershed boundary. Blue lines show the island-wide stream network. North arrow and scale bar included.
|Page 29: 1996 orthophoto base map of the Grafton Lake Lands Study Area. Red outline delineates the study area boundary. Blue lines show stream/watercourse network provided by Bowen Island Municipality. White lines indicate parcel boundaries. North arrow and scale bar (0-960 metres) included.
|Page 30: Concept plan map (Grafton Lake Rezoning Project, March 2015 draft) showing proposed land use zones. Dark green indicates proposed nature preserve (majority of lake and surrounding lands). Light green indicates proposed development nodes (1-4). Orange indicates proposed agricultural area. Red dashed lines show proposed trails; orange dashed lines show existing trails. Green arrow symbols indicate conceptual greenway locations. Key features labelled include Grafton Lake, Mt Gardner, Crown Land, Camp Bow-Isle Lands, Singing Woods Nature Reserve, Bowen Island Ecological Reserve, Mt Apodaca, development lots BL7, BL N1/2 5, BL S1/2 5, Lot A-1, Lot A-2, DL 1348, Harding Rd, Grafton Rd. Legend provided. Prepared by Whitehead Environmental Consultants Ltd., 24 Feb. 2015.
|Page 31: Sensitive Ecosystems and Streams map of the Grafton Lake Lands Study Area on 1996 orthophoto base. Red outline delineates the study area boundary. Colour overlays indicate: orange -- riparian ecosystems; pink/purple -- wetlands (concentrated around Grafton Lake shoreline); light green -- second growth forest (associated ecosystem). Blue lines show stream network. North arrow and scale bar (0-960 metres) included. Mapped by Islands Trust as part of Bowen-Gambier Sensitive Ecosystem Inventory.
|Page 32: Ecosystem mapping for Grafton Lake Rezoning Project prepared by Whitehead Environmental Consultants Ltd., February 2015. Detailed land cover classification map with legend showing: wetland (hatched blue-green), coniferous forest (dark green), deciduous forest (light green), inland bluff (tan), herb-shrub (yellow-orange), logged (light orange), cleared (orange), watershed divide (purple dashed), project lands (black outline). Stream classifications shown by line type: no fish, unknown, fish-present. Trails and roads shown. Named features include Grafton Lake (100m elevation), Terminal Creek, Raven Ck, Rennison Ck, Warbler Ck, Clink Brook, Harding Brook, Bowen Brook, Spooner Brook, Harding Rd, Grafton Rd, Mt Apodaca, Crown Land, Mt Gardner, Conical Hill (Duncan's Hat), Ecological Reserve, Singing Woods Nature Reserve (ITF), Muni. Park, Camp Bow-Isle Lands. North arrow and scale bar included.
Image Descriptions
Page 1: Cover photograph showing Grafton Lake and its outlet area in late autumn/winter conditions. The foreground shows the lake outflow channel lined with dry golden-brown sedge and cattail marsh vegetation. The background shows the forested slopes of Mt Gardner rising above the lake's far shore under a blue sky.
|Page 10: Six-panel photo grid (Figure 1) showing wetland habitats of the Grafton Lake lands: (a) hardhack thicket swamp -- dense reddish-brown shrub stems; (b) sedge wetland -- golden grasses with conifer backdrop; (c) bulrush marsh -- tall aquatic vegetation in standing water; (d) cattail marsh -- cattails with forested hillside; (e) wetland vegetation along lake edges -- across-lake view with Mt Gardner cliffs; (f) sphagnum in a pocket poor fen -- bright green mosses and low vegetation close-up.
|Page 11: Four-panel photo grid (Figure 2) of forested swamp on the west side of Grafton Lake: (a) mossy old-growth conifers with standing wildlife snag; (b) overturned root mass colonized by sword fern; (c) skunk cabbage (Lysichiton americanum) in wetter areas; (d) veteran Sitka spruce trunk.
|Page 13: Six-panel photo grid (Figure 3) of streams and riparian areas: (a-d) four views of Bowen Brook showing clear forested stream with cobble bed; (e) gully between Conical Hill and Mt Gardner -- panoramic forested valley view; (f) narrow forest stream with fern-lined banks.
|Page 15: Four-panel photo grid (Figure 6) of rocky habitats: (a) cliffs on north side of Grafton Lake reflected in calm water; (b) close-up of Mount Gardner cliff face above conifers; (c) moss-covered rocky bluff between trees; (d) small rock outcrop at lake's edge.
|Page 16: Two-panel photo grid (Figure 3 wildlife): (a) Northwestern Salamander on muddy ground adjacent to Raven Brook; (b) Black-tailed Deer hoof prints in soft mud.
|Page 17: Six-panel photo grid (Figure 4) of mature forest: (a-d) tall conifers with mossy forest floors, sword fern understoreys, coarse woody debris, and multi-species canopy; (e) moss-covered downed log; (f) large-diameter western redcedar base.
Page Count
32
Publisher Location
Bowen Island, BC
File Size
1.8 MB
File Format
application/pdf
Geographic Locations
Bowen Island | Grafton Lake | Bowen Island, BC | Canada | Metro Vancouver Regional District | Mount Gardner | Mount Apodaca | Bowen Island Ecological Reserve | Conical Hill (Duncan's Hat) | Terminal Creek | Killarney Creek | Bowen Brook | Raven Brook | Rennison Creek | Warbler Creek | Clink Brook | Harding Brook | Cove Bay
GIS Layer Geometry
polygon
Land Legal Description
DL 1348