Grafton Lake Watershed Study: Report No. 2: 2007-2009
Basics
Title
Grafton Lake Watershed Study: Report No. 2: 2007-2009
Description
AI-generated: This report presents the results of a watershed environmental monitoring and public education project (2007-2009) implemented for the Cove Bay Water System (CBWS) of the Bowen Island Municipality. The study covered four components: a public education and communication (E&C) program using school programs, community media, and events; water quality monitoring of Grafton Lake and its tributary streams; hydrological monitoring of stream flows; and ecological assessment of the Grafton Lake reservoir ecosystem including waterfowl, water levels, and water temperatures. The report identifies contamination sources in the watershed, establishes baseline hydrological and ecological data, and makes 22 specific recommendations for ongoing watershed management.
Date
February 1, 2010
Creator Organization
Whitehead Environmental Consultants Ltd. | Blair Whitehead & Associates
Authors
Alan Whitehead | D.G. Blair-Whitehead
Document Type
Report
Full Text URL
Subject Area
Species Biodiversity > Amphibians | Species Biodiversity > Aquatic animals | Species Biodiversity > Birds | Data Tools & Methods > Citizen science | Ecology | Ecosystems | Policy & Governance > Environmental policy | Ecosystems > Freshwater ecology | Water Resources > Hydrology | Species Biodiversity > Mammals | Policy & Governance > Municipal Planning | Data Tools & Methods > Research data | Ecosystems > Riparian ecology | Water Resources > Water quality | Water Resources | Water-supply | Water Resources > Watershed management | Ecosystems > Wetland ecology
Metadata
Keywords
Grafton Lake
|Grafton Lake watershed
|Cove Bay Water System
|CBWS
|water quality
|water quantity
|hydrology
|Bowen Island
|watershed monitoring
|source water protection
|fecal contamination
|Bacterial Source Tracking
|BST
|stream flow
|water level
|lake ecosystem
|waterfowl
|beaver
|red-legged frog
|Terminal Creek
|Bowen Brook
|septic systems
|drinking water
|Drinking Water Protection Act
|education and communication
|Watershed Quest
|stage-discharge
Time Period
2007-2009
Relationship - isPartOf
Document ID
2605031441
Relationship - hasPart
Document ID
2605031441
Document ID
2605031441
Document ID
2605031441
Document ID
2605031441
Document ID
2605031441
Copyright holder
Not found
Document Filename
whitehead_blair_2010_watershed_report_202605031441.pdf
Storage Location
analysis/bowen-municipality
Key Findings
AI-generated: Source water quality for the Cove Bay Water System is relatively good but impacted by human fecal contamination in several tributary streams and the Grafton Lake reservoir (from failing septic systems and recreational swimming). Elevated concentrations of metals (Al, Cu, Zn), nutrients, and hydrocarbons were detected in streams draining commercial/residential areas. An automated hydrometric station was installed on Bowen Brook providing real-time water level data; average annual water yield estimated at 17.7 m3/d/ha. Eighteen wildlife species dependent on Grafton Lake wetlands were identified, including the blue-listed red-legged frog. Lake water levels fluctuate approximately 1 m annually between ~105.3 and 106.3 m. The public education campaign increased community understanding of source water protection.
Methodology
Water quality grab samples collected at 25 sites on three occasions (August 2007, June 2008, October 2008) and analyzed for physical, chemical, nutrient, metal, hydrocarbon, and bacteriological parameters. Bacterial Source Tracking (BST) used to distinguish human from animal fecal contamination. Automated hydrometric station installed on Bowen Brook at Harding Road for continuous stream stage monitoring at 15-minute intervals. Stage-discharge relationship developed using Volunteer Stream Flow Monitoring Project data. Ecological monitoring included waterfowl census by boat and on foot, water level monitoring via staff gauge and automated sensors, and lake water temperature monitoring at 1-m depth intervals using recording thermistors. Education program evaluated through community surveys and focus groups.
Map Descriptions
Page 14 (Map 1): Surface Water Quality Sampling Sites, Grafton Lake Watershed and Subwatersheds, Bowen Island. Colour topographic map showing the Grafton Lake watershed boundary (purple bold line), 25 numbered water quality sampling sites, subwatershed boundaries, drilled and dug wells, licensed water intakes, streams, municipal park areas, wetlands, lakes/ponds/reservoir (Grafton Lake shown in blue at ~105 m elevation), and public trails. Major landmarks include Mount Gardner (North Summit 717 m, South Summit 724 m), Apodaca Mountain (480 m), Bowen's Knob (305 m), and Josephine Lake. Scale bar 0-1500 m. Prepared by Whitehead Environmental Consultants Ltd., 20 August 2008. Base map courtesy of Bowen Island Municipality and Bowen Island Conservancy GIS.
Graph Descriptions
Appendix 3: Graphs A through I showing dissolved and particulate portions of total metals content in surface water samples from Bowen Brook, Harding Brook, and Billington Creek at three sampling dates (August 2007, June 2008, October 2008). Note: graph axis labels did not extract cleanly from PDF due to rotated text encoding — graphs best viewed in original document. Main body contains Graphs 1–9 (inline) showing conductivity, pH, nitrate, total phosphorus, fecal coliform, stream stage, and lake water temperature data.
Image Descriptions
Pages 106-120 (Appendix 4 Photographs): Photo 1: Marsh wetland at east end of Grafton Lake viewed from outlet dam, May 2007. Photo 2: Swamp wetland in forest on west side of Grafton Lake, May 2007. Photo 3: Marsh on northeast side of Grafton Lake viewed from cliff, May 2007. Photo 4: Outer edge of marsh on southwest side, July 2008. Photo 5: Automated water quality monitoring apparatus in CBWS chlorination shed. Photo 6: Snow and ice on Grafton Lake, February 2009. Photo 7: Outlet dam and beaver dam debris removed by BIM staff, March 2009. Photo 8: Outlet dam during summer draw-down, July 2009. Photo 9: Outlet dam with ropes attached to outlet pipes to overcome beaver damming, August 2009. Photo 10: Lake bed in marsh exposed by draw-down, August 2009. Photo 11: Marsh sediments exposed at east end during draw-down, August 2009. Photo 12: Yellow pond lily exposed during draw-down, August 2009. Photo 13: Deployment of recording temperature sensors, July 2008. Photo 14: Buoys marking temperature monitoring system, July 2008. Photo 15: Temperature monitoring device beside Grafton Lake, March 2009. Photo 16: Temperature monitoring system after retrieval, July 2009. Photo 17: Canada geese near nest, April 2009. Photo 18: Canada Goose nest on cliff ledge, May 2009. Photo 19: Canada Goose egg preyed upon by Common Raven, May 2007. Photo 20: Mallard ducks in marsh during draw-down, August 2009. Photo 21: Beaver lodge, May 2009. Photo 22: Red alder felled by beaver, May 2009. Photo 23: Newest beaver lodge at east end, February 2010. Photo 24: Stumps of trees cut by beaver beside Terminal Creek, February 2010. Photo 25: Columbia black-tailed deer swimming across Grafton Lake, May 2009. Photo 26: Pacific tree frog on water shield leaves, July 2009. Photo 27: Contact recreation at rocky point, July 2008. Photo 28: Crushed vehicles at Buchanan Road quarry, April 2009.
Page Count
120
Publisher Location
Bowen Island, B.C.
File Size
6.2 MB
File Format
application/pdf
Geographic Locations
Grafton Lake | Bowen Island | British Columbia | Canada | Howe Sound | Terminal Creek | Bowen Brook | Mount Gardner | Apodaca Mountain | Josephine Lake | Cove Bay | Snug Cove
Street Address
981 Artisan Lane, Bowen Island, B.C. V0N 1G0 | P.O. Box 41, Bowen Island, B.C. V0N 1G0 | R.R.1 CH-11, Bowen Island, B.C. V0N 1G0 | Harding Road | Buchanan Road | Adams Road | Sunset Road