Whatshan Project Water Use Plan Whatshan Reservoir Vegetation Monitoring Implementation Year 10 Reference: WGSMON-2 Whatshan Water Use Plan Monitoring Program: Reservoir Vegetation Monitoring – Technical Report Study Period: 2015 G3 Consulting Limited 206-8501 162nd Street Surrey, BC, V4N 1B2 September 27, 2016 Whatshan Reservoir Vegetation Monitoring 2016 Technical Report Prepared for: BC Hydro and Power Authority 6911 Southpoint Drive Burnaby, BC Canada, V3N 4X8 Prepared by: G3 Consulting Ltd. 206-8501 162 nd Street Surrey, B.C. Canada V4N 1B2 www.g3consulting.com September 2016 Acknowledgments Dr. Greg Thomas (Project Manager/Senior Scientist) on behalf of G3 Consulting Ltd., would like to acknowledge the assistance of several individuals involved throughout this program. In particular, we would like to thank Ms. Toby Jones (Natural Resources Specialist) and Dr. Guy Martel (Ecosystem Scientist) with BC Hydro for their direction and support on all aspects of this program. Dr. Thomas would also like to thank the competent efforts of Mr. Alex Caldicott for field supervision and primary contributor to this report, Dr. Lin Lu (statistical analyses), Mr. Chris Adamson (GIS/Satellite analysis) and Ms. Isabel McFetridge, Mr. Adrian MacKay and Ms. Christine Latos for field and office support. Ms. Wendy Hannon is acknowledged for administrative support. Mr. Vic Mazur is acknowledged for his competent assistance as boat operator during field work. Without the dedicated efforts of these individuals, this report would not have been possible. Suggested Citation G3 Consulting Ltd. 2016. WGSMON-2: Whatshan Reservoir Vegetation Monitoring Program, Phase 3 (2015). Prepared for BC Hydro and Power Authority, Burnaby, BC by G3 Consulting Ltd., Surrey, BC. 37 pages + Appendices. © G3 Consulting Ltd. Whatshan Reservoir Vegetation Monitoring Table of Contents BC Hydro and Power Authority Year 10 (2015) Technical Report CONTENTS Executive Summary _________________________________________________________ iii 1.0 Introduction _____________________________________________________________ 1 1.1 Study Objectives _______________________________________________________ 1 1.2 Background & Project Rationale ___________________________________________ 2 1.2.1 Reservoir Characteristics ___________________________________________________ 2 1.2.2 Reservoirs & Macrophyte Ecology ____________________________________________ 4 1.3 Study Area ____________________________________________________________ 4 1.3.1 Fisheries ________________________________________________________________ 5 1.3.2 Wildlife __________________________________________________________________ 5 1.4 Study Sites ____________________________________________________________ 5 1.4.1 Phase 1 (2006) ___________________________________________________________ 5 1.4.2 Phase 2 (2011) & Phase 3 (2015) ____________________________________________ 5 1.5 Phase 1 & 2 Summaries _________________________________________________ 6 1.5.1 Phase 1 Summary_________________________________________________________ 6 1.5.2 Phase 2 Summary_________________________________________________________ 6 2.0 Study Design & Methods ___________________________________________________ 7 2.1 Start-up Meeting & Communications ________________________________________ 7 2.2 Pre-Field______________________________________________________________ 7 2.2.1 Summary of Existing Information _____________________________________________ 8 2.3 Field Work ____________________________________________________________ 8 2.3.1 Research Vessel __________________________________________________________ 9 2.3.2 Whatshan Reservoir Environmental & Safety Plan _______________________________ 9 2.3.3 Study Sites ______________________________________________________________ 9 2.3.4 Site Layout _____________________________________________________________ 10 2.3.5 Study Sites _____________________________________________________________ 11 2.3.6 Collection of Biological & Physical Data _______________________________________ 12 2.3.7 Bathymetry _____________________________________________________________ 15 2.3.8 Site Photos, Data & Observations ___________________________________________ 15 2.4 Post Field ____________________________________________________________ 15 2.4.1 Taxonomy ______________________________________________________________ 15 2.4.2 Reference Collection ______________________________________________________ 15 2.4.3 Photographic Database ___________________________________________________ 16 2.5 Satellite Analyses ______________________________________________________ 16 2.5.1 Vegetation Classification & Satellite Model Refinement ___________________________ 16 2.6 Macrophyte Community Data Analysis _____________________________________ 18 2.7 QA/QC & Data management _____________________________________________ 18 3.0 Results ________________________________________________________________ 20 3.1 Reservoir Elevation ____________________________________________________ 20 3.2 Macrophyte Observations _______________________________________________ 20 3.2.1 Study Sites _____________________________________________________________ 20 3.2.2 Macrophyte Community Coverage ___________________________________________ 22 3.2.3 Macrophyte Community Structure ___________________________________________ 25 3.2.4 Macrophyte Community Spectral Classes _____________________________________ 27 3.2.5 Macrophyte Bed Elevations ________________________________________________ 27 3.3 Biophysical Observations ________________________________________________ 28 3.3.1 Water Quality ___________________________________________________________ 28 3.3.2 Substrate Characteristics __________________________________________________ 31 3.4 Anthropogenic Activities _________________________________________________ 31 i G3 Consulting Ltd. Whatshan Reservoir Vegetation Monitoring Table of Contents BC Hydro and Power Authority Year 10 (2015) Technical Report 4.0 Summary & Discussion ___________________________________________________ 32 5.0 References _____________________________________________________________ 35 Taxonomy References _____________________________________________________ 37 List of Tables Table E-1: BC Hydro Status of Objectives Table Table 2-1: Quadrat Distribution Table 2-2: Spectral Bands Considered in Analysis Table 3-1: Long-term Monitoring Site Emergent Macrophyte Areas Table 3-2: Long-term Monitoring Site Submergent Macrophyte Areas Table 3-3: Overall Macrophyte Area Estimates Table 3-4: Submerged Macrophyte Community Classes Table 3-5: Submerged Macrophyte Elevations Table 4-1: BC Hydro Status of Objectives Table List of Figures Figure 2-1: Whatshan Lake Reservoir Elevation (m) September 1 - September 30 (2006, 2011 & 2015) Figure 2-2: Example Layout Schematic for Macrophyte Site Surveys Appendices Appendix 1: Figures Appendix 2: Photos Appendix 3: Charts Appendix 4: Tables Appendix 5: Macrophyte Ecology Appendix 6: Macrophyte Raw Data Appendix 7: Basemaps ii G3 Consulting Ltd. Whatshan Reservoir Vegetation Monitoring Executive Summary BC Hydro and Power Authority Year 10 (2015) Technical Report EXECUTIVE SUMMARY G3 Consulting Ltd. (G3) was retained by BC Hydro to assess macrophyte communities in the Whatshan Reservoir. A Water Use Planning Process was initiated for Whatshan Reservoir in 2002 and resulted in development of changes to water use at Whatshan Reservoir to promote recreational use of the waters. A three phase vegetation monitoring study (Baseline, 2006; 5-Year Post Changes, 2011; and, 10-Year Post Changes, 2016) was implemented to assess potential effects associated with changes to the operations which included the following: an increase in the minimum year-round water elevations to 636.5 m (previously 634 m); and, annual increases in minimum reservoir elevation occurring earlier in the year (i.e., minimum of 639 m by May 15th and a minimum of 640.35 m between June 15th and October 1st of each year). Objectives and management questions were established prior to commissioning the Whatshan Reservoir Vegetation Monitoring Program. Study design and applied methodologies were developed to address study-specific objectives and management questions. The main objective of the Whatshan Reservoir macrophyte survey was to reduce uncertainty related to effects of reservoir operations on Whatshan Lake Reservoir by: monitoring key aquatic vegetation sites (Bennett et al. 2002); and, examining vegetation community boundary shifts. The key management question identified in the WGSMON-2 Terms of Reference (BC Hydro, 2005) examines whether reservoir vegetation is affected by changes in the operation of the Whatshan Lake Reservoir. Table ES-1: BC Hydro Status of Objectives Table Year Six Year Ten Management Objectives Management Hypotheses (2011) (2015) Question Status Status H1: The area of emergent Tentatively vegetation will decrease as Supported, to Rejected Reduce uncertainty related a consequence of extended be confirmed to the effects of reservoir inundation. in 2015 operations on reservoir H1a: The species composition of Not as yet vegetation in the Whatshan emergent vegetation will addressed, to Do changes in the Accepted Lake Reservoir. Monitoring change as a consequence be assessed operation of the will focus on key locations of extended inundation. in 2015 Whatshan Lake where aquatic vegetation is Reservoir affect H2: The area of submerged Tentatively present (Bennett et al. vegetation will increase as a Supported, to reservoir