Etobicoke and Mimico Creeks Watersheds Technical Update Report AQUATIC SYSTEM - INSTREAM BARRIERS TO FISH PASSAGE TABLE OF CONTENTS 9.0 AQUATIC SYSTEM - INSTREAM BARRIERS TO FISH PASSAGE ............................ 9-1 9.1 Watershed Objectives, Indicators and Targets .......................................................... 9-1 9.2 Objectives of Technical Update .................................................................................. 9-2 9.3 Data Sources, Field Surveys and Methods ................................................................ 9-3 9.3.1 Desktop Assessment .............................................................................................. 9-3 9.3.2 Field Surveys ........................................................................................................... 9-5 9.3.3 Data Synthesis and Analyses ................................................................................. 9-6 9.4 Existing Conditions and Interpretation ....................................................................... 9-7 9.4.1 Fish Species in Etobicoke and Mimico Creeks ...................................................... 9-8 9.4.2 On-Line Stormwater Management Ponds in the Etobicoke and Mimico Creeks Watersheds ............................................................................................................. 9-9 9.4.3 Channelization of Etobicoke and Mimico Creeks ................................................ 9-10 9.4.4 Impervious Cover in Etobicoke and Mimico Creeks Watersheds........................ 9-13 9.4.5 Overview of Barriers within Etobicoke Creek Watershed ..................................... 9-16 9.4.6 Overview of Barriers within Mimico Creek Watershed ......................................... 9-30 9.4.7 Overall Summary of Existing Conditions .............................................................. 9-38 9.5 Decision Criteria for Selecting Prioritiy Barriers For Management .......................... 9-38 9.5.1 Fish IBI Scores and Natural Stream Habitat Areas .............................................. 9-39 9.5.2 Rehabilitation Projects .......................................................................................... 9-41 9.5.3 Riparian Vegetation Cover .................................................................................... 9-43 9.5.4 Small Scale Barriers .............................................................................................. 9-43 9.6 Management Recommendations –Etobicoke Creek Priority Barriers ..................... 9-45 9.6.1 Category A - Lake to Headwaters ......................................................................... 9-45 9.6.2 Category B – Extending Existing Natural Habitat ................................................. 9-49 9.6.3 Category C – Stewardship .................................................................................... 9-51 9.7 Management Recommendations - Mimico Creek Priority Barriers ......................... 9-54 9.7.1 Category A – Lake to Headwaters ........................................................................ 9-54 9.7.2 Category B – Extending Existing Natural Habitat ................................................. 9-58 9.7.3 Category C – Stewardship .................................................................................... 9-61 9.8 Overall Summary of Management Considerations for Etobicoke and Mimico Creeks Watersheds ............................................................................................................... 9-63 9.9 References ................................................................................................................ 9-64 9.10 Appendix 9-A – Assessment Form for Barrier Survey .............................................. 9-66 Toronto Region Conservation, Final Draft October 2010 Etobicoke and Mimico Creeks Watersheds Technical Update Report LIST OF FIGURES Figure 9-1: Fish Sampling Locations in Etobicoke and Mimico Creeks Watersheds ............... 9-4 Figure 9-2: Sheet Flow Conditions Preventing Fish Passage South-West of Clark Boulevard and West Drive. ........................................................................................................ 9-7 Figure 9-3: Graphic Depicting Fish Passage Calculation. ......................................................... 9-7 Figure 9-4: Location of On-line Stormwater Management Ponds in Etobicoke and Mimico Creeks Watersheds ................................................................................................ 9-11 Figure 9-5: Channelized Streambed of Etobicoke and Mimico Creeks Watersheds ............. 9-12 Figure 9-6: Percent Impervious Cover in Etobicoke and Mimico Creeks Watersheds, 2008 . 9-14 Figure 9-7: Natural Flow in Etobicoke West Branch Subwatershed ....................................... 9-15 Figure 9-8: Impacted Flow in Lower Etobicoke Subwatershed ............................................... 9-15 Figure 9-9: Impacted Flow in Mimico Creek Watershed ......................................................... 9-15 Figure 9-10: Existing Instream Structures - Etobicoke Creek Watershed ............................... 9-17 Figure 9-11: Lower Etobicoke Existing Instream Structures, including: Etobicoke Main Branch, Tributary 4, and Little Etobicoke ............................................................................ 9-19 Figure 9-12: Weir at CN Railway Line ....................................................................................... 9-21 Figure 9-13: Spring Creek Existing Instream Structures within Spring Creek Subwatershed 9-23 Figure 9-14: Erosion North-East of Drew Road and Bramalea Road ...................................... 9-24 Figure 9-15: Chinguacousy Park Dam North-West of Queen Street and Central Park Road . 9-24 Figure 9-16: Channel Erosion at Avondale Tributary at Dixie and Clarke ............................... 9-25 Figure 9-17: Upper Etobicoke Existing Instream Structures including: Tributary 3, Etobicoke West Branch and Etobicoke Headwaters Subwatersheds .................................... 9-27 Figure 9-18: Flow Dissipating Weir in Tributary 3 South-West of Midway Boulevard and Dixie Road ........................................................................................................................ 9-28 Figure 9-19: Weir Structure in West Tributary located North-West of Courtney Park Drive and Tomken Road in 2006(a) low flow and 2008 (b) high flow. ................................... 9-28 Figure 9-20: Step Weir at Drew Road East of Dixie Road. ....................................................... 9-29 Figure 9-21: Perched Culvert North of 407 West of Dixie Road. ............................................. 9-29 Figure 9-22: Existing Instream Structures in Mimico Creek Watershed .................................. 9-31 Figure 9-23: Existing Instream Structures in Mimico Creek Main Branch ............................... 9-33 Figure 9-24: Existing Instream Structures in Mimico Creek East Branch ............................... 9-35 Figure 9-25: Damaged Infrastructure south-west of Clark Blvd. and Walker Dr. (MCE 103) .. 9-36 Figure 9-26: Existing Instream Structures in Mimico Creek West Branch .............................. 9-37 Figure 9-27: Index of Biotic Integrity - Etobicoke and Mimico Creeks Watersheds ................ 9-40 Figure 9-28: Rehabilitation Projects – Etobicoke and Mimico Creeks Watersheds (2009) .... 9-42 Figure 9-29: Riparian Cover for Etobicoke and Mimico Creeks Watersheds .......................... 9-44 Figure 9-30: Priority Category A – Lake to Headwaters- Etobicoke Creek Watershed * ........ 9-46 Figure 9-31: Weir at Toronto Golf Club Bridge (ECLOW006) .................................................. 9-48 Figure 9-32: Weir 500m South of Q.E.W. (ECLOW011) .......................................................... 9-48 Figure 9-33: Weir at Bloor Street West of Dixie Mill Road (ECLOW029) ................................. 9-48 Figure 9-34: Weir at Britannia Road and East Road (ECLOW039) ......................................... 9-48 Figure 9-35: Weir South of Queen Street West of Centre Street (MEE023) ............................ 9-49 Figure 9-36: Natural Barriers Weybridge Park (MEE033), Near Valleywood Development (MEE059), North of Mayfield between Hurontario and Kennedy (MEE060) ......... 9-49 Figure 9-37: Priority Category B – Extending Existing Natural Habitat- Etobicoke Creek Watershed * ............................................................................................................ 9-50 Figure 9-38: Priority Category C – Stewardship Projects – Etobicoke Creek Watershed ....... 9-52 Toronto Region Conservation, Final Draft October 2010 Etobicoke and Mimico Creeks Watersheds Technical Update Report Figure 9-39: Rock obstruction north-east of East Gate Parkway and Tomken Road (ECLE031) ................................................................................................................................ 9-53 Figure 9-40: Old sediment fence north-east of Bovaird Road and 410. (SPHL009) ............... 9-53 Figure 9-41: Priority Category A – Lake to Headwaters – Mimico Creek Watershed ............. 9-55 Figure 9-42: Weir at Q.E.W. (MC005) ....................................................................................... 9-56 Figure 9-43: Weir at Q.E.W. (MC007) ....................................................................................... 9-56 Figure 9-44: Weir 500m south of Berry Road (MC011) ..........................................................