Schedule ‘C’ Environmental Assessment for 16th Avenue between Yonge Street and Woodbine Avenue Appendix M Fluvial Geomorphology Accessible formats are available upon request. CLASS ENVIRONMENTAL ASSESSMENT STUDY FLUVIAL GEOMORPHIC COMPONENT 16TH AVENUE FROM YONGE STREET TO WOODBINE AVENUE Report Prepared for: HDR CORPORATION Prepared by: MATRIX SOLUTIONS INC. Version 3.0 July 2018 Mississauga, Ontario Suite 200, 2500 Meadowpine Blvd. Mississauga, ON L5N 6C4 T 905.877.9531 F 289.323.3785 www.matrix-solutions.com CLASS ENVIRONMENTAL ASSESSMENT STUDY - FLUVIAL GEOMORPHIC COMPONENT 16TH AVENUE FROM YONGE STREET TO WOODBINE AVENUE Report prepared for HDR Corporation, July 2018 reviewed by Tatiana Hrytsak, M.Sc. John Parish, P.Geo. Fluvial Geomorphology Specialist Principal Fluvial Geomorphologist Ahmed Siddiqui, M.Sc., CAN-CISEC Sam Bellamy, P.Eng. Fluvial Geomorphology Specialist Principal Water Resources Engineer DISCLAIMER We certify that this report is accurate and complete and accords with the information available during the site investigation. Information obtained during the site investigation or provided by third parties is believed to be accurate but is not guaranteed. We have exercised reasonable skill, care, and diligence in assessing the information obtained during the preparation of this report. This report was prepared for HDR Corporation. The report may not be relied upon by any other person or entity without our written consent and that of HDR Corporation. Any uses of this report by a third party, or any reliance on decisions made based on it, are the responsibility of that party. We are not responsible for damages or injuries incurred by any third party, as a result of decisions made or actions taken based on this report. 23456-522 16th Ave Yonge to Woodbine 2018-07-23 final V3.docx ii Matrix Solutions Inc. TABLE OF CONTENTS 1 INTRODUCTION ................................................................................................................................ 1 2 BACKGROUND REVIEW .................................................................................................................... 3 2.1 Geology and Physiography ................................................................................................. 3 2.2 Previous Studies .................................................................................................................. 5 3 REACH DELINEATION ....................................................................................................................... 6 4 HISTORICAL ASSESSMENT ................................................................................................................ 6 5 FIELD ASSESSMENT .......................................................................................................................... 8 5.1 Rapid Assessments - Methods ............................................................................................ 9 5.2 Rapid Assessments - Results ............................................................................................. 10 5.2.1 German Mills Creek ............................................................................................. 10 5.2.2 Beaver Creek ........................................................................................................ 11 5.2.3 Rouge River .......................................................................................................... 12 6 MEANDER BELT WIDTH .................................................................................................................. 14 6.1 Preliminary Belt Width ...................................................................................................... 15 6.2 Factor of Safety ................................................................................................................. 15 7 CROSSING SPAN RECOMMENDATIONS ......................................................................................... 16 8 CONCLUSIONS AND NEXT STEPS .................................................................................................... 19 9 REFERENCES ................................................................................................................................... 20 LIST OF FIGURES FIGURE 1 Study Area from Yonge to Woodbine Avenue ............................................................... 2 FIGURE 2 Surficial Geology from Yonge to Woodbine Avenue ..................................................... 4 LIST OF TABLES TABLE 1 Average Migration Rates Determined from the Aerial Imagery .................................... 8 TABLE 2 Rapid Geomorphic Assessment Classification ............................................................... 9 TABLE 3 Summary of Rapid Geomorphic Assessment Results .................................................. 13 TABLE 4 Summary of Rapid Stream Assessment Technique Results ......................................... 14 TABLE 5 Summary of Meander Belt Width Delineation ............................................................ 15 TABLE 6 Crossing Recommendations from a Geomorphic Perspective .................................... 17 APPENDICES APPENDIX A Site Photographs APPENDIX B Rapid Assessment Results APPENDIX C Belt Width Delineation Procedures (Parish 2004) APPENDIX D Individual Crossing Figures 23456-522 16th Ave Yonge to Woodbine 2018-07-23 final V3.docx iii Matrix Solutions Inc. 1 INTRODUCTION The Regional Municipality of York has retained HDR Corporation (HDR) to undertake a Class Environmental Assessment (EA) study for 16th Avenue from Yonge Street to Woodbine Avenue. The study will evaluate existing conditions and determine specific improvements. Matrix Solutions Inc. has been retained by HDR to provide fluvial geomorphological assessment of the associated watercourse crossings as part of the Class EA. To complete the assessment, the following work plan was undertaken: • collect and review pertinent background information, such as topographic mapping, historical aerial photographs, and any previous reports that would pertain to the watercourses in the study area • use available mapping to confirm channel reach boundaries • where possible, complete channel migration analyses in order to determine 100-year erosion rates • delineate the meander belt width on a reach basis at each of the crossing structures based on mapping and aerial photographs • complete field reconnaissance to confirm existing geomorphic conditions, document any evidence of active erosion, and confirm appropriateness of the desktop results • assess appropriateness of crossing structures in relation to channel migration and adjustment The study area includes three watercourse crossings: German Mills Creek, Beaver Creek, and the Rouge River (Figure 1). The surrounding area is fully urbanized and as a result, riparian corridors are minimal. 23456-522 16th Ave Yonge to Woodbine 2018-07-23 final V3.docx 1 Matrix Solutions Inc. Easting (m) Study Area Watercourse Expressway / Highway W Road Major MacKenzie Drive East YongeStreet R ou ge R iv er k e e r C s l l i M n a m r e G UV404 Northing(m) 16th Avenue BayviewAvenue B ea v er C r ee k WoodbineAvenue 1:20,000 m 200 0 200 400 Referenc e: Data obtained from GeoBase® used under license. Imagery (2015) obtained from York Region used under license. NAD 1983 UTM Zone 17N HDR Corporation 16th Ave. Class Environmental Study UV407 Highway 7 Study Area from Yonge to Woodbine Avenue Date: Project: Technical: Rev iewer: Drawn: 24 Mar 2017 23456 T. Hrytsak J. Parish C. Curry Disclaim er: The inform ation contained herein may be com piled from numerous third party m aterials that are subject to periodic change Figure without prior notification. While every effort has been made by Matrix Solutions Inc. to ensure the accuracy of the information presented at the time of publication, Matrix Solutions Inc. assumes no liability for any errors, om issions, or inaccuracies in the third party material. I:\HDRCor por ation\23456\Figur esandTables \HYD\2017\Repor t\Figure- 1-Study _Area_from _Yonge_to_Woodbine_Av eue.mx d 1 2 BACKGROUND REVIEW 2.1 Geology and Physiography The study area is situated within the Peel Plain physiographic region (Chapman and Putnam 1984). Within the confines of the study area, the Peel Plain physiographic region is characterized as a gently sloping till plain formed of dense, glacially derived, clay deposits containing both bevelled till and drumlinized landform features. Surficial geology within the study area consists of alternating arrangements of fine-textured glaciolacustrine deposits and stone-poor carbonate-derived silty to sandy till (Figure 2). The fine-textured glaciolacustrine deposits are generally defined by massive well-laminated silt and clay with minor sand and gravel inclusions. German Mills Creek and the Rouge River are all characterized by these fine-textured deposits. The north section of Beaver Creek consists of the stone-poor silty to sandy till deposits, while the south section is characterized by the same fine-textured deposits. 23456-522 16th Ave Yonge to Woodbine 2018-07-23 final V3.docx 3 Matrix Solutions Inc. StudyArea Wa terco urse ExpresswaHighwa y/ y W Roa d Surficial Geology 5b : Stone-po5b: ca o rbo r, na te-derivedsandsiltyto ytill 5d : Glac5d: iolac ustrine-derivedclayeysiltyto till 8a : Ma8a: ssive-welllam ina ted Ma jor Ma c Kenzie Drive East 9c: Foresho9c: re-ba sinadep l o sits 19: Mo 19: d ernalluvial dep o sits 20: Orga 20: nicdep o sits Yonge Street Yonge R ou ge R iv