Meadowcliffe Drive Erosion Control Project
Toronto and Region Conservation Authority Environmental Study Report
March 1, 2010
5 Shoreham Drive, Downsview, Ontario M3N 1S4
ACKNOWLEDGEMENTS
The Toronto and Region Conservation Authority gratefully acknowledges the efforts and contributions of the following people participating in the planning and design phases of the Meadowcliffe Drive Erosion Control Project:
Al Sinclair Meadowcliffe Drive Resident Barbara Heidenreich Ontario Heritage Trust Beth McEwen City of Toronto Bruce Pinchin Shoreplan Engineering Limited Councilor Brian Ashton City of Toronto Councillor Paul Ainslie City of Toronto Daphne Webster Meadowcliffe Drive Resident David Argue iTransConsulting Limited Don Snider Meadowcliffe Drive resident Janet Sinclair Meadowcliffe Drive Resident Jason Crowder Terraprobe Limited Jim Berry Toronto and Region Conservation Authority Joe Delle Fave Toronto and Region Conservation Authority Joseph Palmissano iTransConsulting Limited Larry Field Toronto and Region Conservation Authority Laura Stephenson Toronto and Region Conservation Authority Lindsay Prihoda Toronto and Region Conservation Authority Lori Metcalfe Guildwood Village Community Association Mark Preston Toronto and Region Conservation Authority Mike Tanos Terraprobe Limited Moranne McDonnell Toronto and Region Conservation Authority Nancy Lowes City of Toronto Nick Saccone Toronto and Region Conservation Authority Patricia Newland Toronto and Region Conservation Authority Paul Albanese City of Toronto Peter Xiarchos M.P.P Lorenzo Berardinetti’s Office Susan Scinocca Meadowcliffe Drive Resident Sushaliya Ragunathan M.P.P Lorenzo Berardinetti’s Office Timo Puhakka Guildwood Village Community Association Trevor Harris Meadowcliffe Drive Resident Tudor Botzan Toronto and Region Conservation Authority
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EXECUTIVE SUMMARY
Toronto and Region Conservation Authority (TRCA) continues to work towards ensuring healthy rivers and shorelines, greenspace and biodiversity, and sustainable communities. One key step in this process is the design and implementation of shoreline stabilization projects along the Scarborough bluffs. These projects serve to remediate erosion prone zones, and to rehabilitate and enhance key natural areas and community focal points. Several decades of important waterfront work has been carried out by TRCA in partnership with waterfront communities to protect and preserve the waterfront for present and future generations.
TRCA is interested in undertaking remedial erosion control works along a portion of the Lake Ontario shoreline from Bellamy Ravine to Bluffers Park, one of the last unprotected sectors of the Scarborough bluffs in the City of Toronto. The project site spans approximately 1,400 m of shoreline from Bluffers Park, East Beach to Bellamy Ravine (also known as Gates Gully).
At the request of several homeowners who expressed concern over the loss of property and the potential long-term risk to their homes, TRCA began monitoring erosion rates on Meadowcliffe Drive in 1985. Several studies have been completed along this shoreline sector; however the most significant report was a geotechnical report conducted on behalf of TRCA by Terraprobe in 2006, which identified acceleration in the erosion rate. This study concluded there would be a significant loss of property and infrastructure, as well as a risk to public safety if mitigative measures were not undertaken along the Meadowliffe shoreline sector.
TRCA’s project objective is to provide long-term protection against erosion by reducing wave energy, protecting the toe of the bluffs from wave energy, stabilizing slopes and enhancing natural processes. As a consequence, risk to public safety and infrastructure will be reduced, passive recreational opportunities will be increased, and aquatic and terrestrial habitat conditions as well as aesthetics will be improved. TRCA has examined a number of alternatives to achieve these objectives including headland beach systems, groynes, and breakwaters.
As part of the Class Environmental Assessment (Class EA) process, TRCA retained Shoreplan Engineering and Terraprobe to complete a detailed review and analysis of the existing conditions along the designated project area and assist with the development of alternative long-term remedial solutions to address the risk to public safety. Results of these investigations indicate that over the next 100 years, a substantial loss of highly valuable recreational, heritage and ecological land is projected, affecting numerous residential dwellings along the crest of the Scarborough Bluffs.
In light of this information, a range of solutions were developed which recognized negative and positive attributes associated with each. To assist with the evaluation of the alternative options and provide input into the planning and design process, a Community Liaison Committee or CLC was formed. Composed of technical staff, stakeholders, provincial agency staff, community activists and interested members of the public, the CLC became an integral part of the Class EA process. Through a series of CLC meetings, a range of alternative options were considered, from traditional solutions such as cobble beaches and breakwaters. In addition to providing feedback on technical and economic considerations, the members provided great insight into the importance of preserving the Scarborough Bluffs.
The preferred solution determined through the Class EA process is a shoreline treatment consisting of cobble beach anchored by a series of parallel headlands which will protect 600 metres (m) of eroding bluff below Meadowcliffe Drive. The headlands will be constructed with large (3-5 tonne) armour stones, measuring between 80 to 100 m in length and spaced 100 to 150 m apart. The area between the headlands will consist of rubble material covered with a
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layer of beach cobble. The beach cobbles will be dynamically stable, and the profile shape will adjust to different wave conditions and water levels over time. The preferred solution also considers the potential need for a buttress at the base of the bluffs at the east end of the shoreline sector to reduce slope recession.
TRCA identified five construction access options and evaluated these options to determine the preferred route. The preferred option is to access the site from the east via TRCA’s existing service road which provides shoreline access from the Guild Inn. TRCA has taken measures to address public concerns related to this route to ensure that all impacts are mitigated.
Upon identifying the preferred solution, TRCA completed a detailed environmental analysis to determine any required mitigation measures. Information gathered through this process has informed the detailed design process. Working with representatives from City of Toronto, Ministry of Natural Resources, Fisheries and Oceans Canada, and Transport Canada, TRCA will prepare a screening report to fulfill the requirements of the Canadian Environmental Assessment Act. This screening report will facilitate the necessary federal approvals that will be required to implement the project.
Capital funding for the proposed works has been identified in TRCA’s 2010 – 2014 budget, with works to be carried out between the period of July 1 – March 31 annually. Given the nature of coastal interventions over the past 50 years across North America, TRCA anticipates that an adaptive management approach will be necessary, to allow modifications to the overall design based on continued monitoring and evaluation of the built structures, shoreline and slope recession.
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TABLE OF CONTENTS 1.0 INTRODUCTION ...... 1
1.1 Relationship of the Undertaking to the Environmental Assessment Act...... 1 1.2 Purpose of the Undertaking ...... 3 1.3 Site Description ...... 3 1.4 General Description of the Undertaking ...... 5 1.5 Rationale for the Undertaking...... 6 2.0 BACKGROUND...... 7
2.1 History of the Problem...... 7 2.2 Identification of Previous Studies ...... 9 2.2.1 Geotechnical Reports...... 9 2.2.2 Planning Documents ...... 10 2.2.3 Aquatic and Terrestrial Habitat Reports ...... 12 2.2.4 Socioeconomic and Cultural Heritage Studies ...... 13 2.3 Justification of Conservation Authority Involvement ...... 14 3.0 BASELINE ENVIRONMENTAL INVENTORY ...... 14
3.1 Location...... 15 3.2 Existing Site Conditions ...... 16 3.2.1 Physical Environment ...... 16 3.2.2 Biological Environment...... 30 3.2.3 Cultural Environment...... 39 3.2.4 Socioeconomic Environment ...... 43 3.2.5 Engineering/Technical...... 45 4.0 DESCRIPTION OF PRELIMINARY ALERNATIVE CONCEPTS ...... 46
4.1 Preliminary Alternative Concepts...... 46 4.1.1 “Do-Nothing” Alternative...... 46 4.1.2 Preliminary Concept 1a – Headland Beach, Meadowcliffe Drive only...... 47 4.1.3 Preliminary Concept 1b – Headland Beach, bluff protection over full project site ...... 48 4.1.4 Preliminary Concept 2a – Groyne/headland beach, Meadowcliffe Drive only...... 49 4.1.5 Preliminary Concept 2b – Groyne/headland beach, bluff protection over full project site ...... 50 4.1.6 Preliminary Concept 3 – Breakwater + cobble beach...... 51 4.1.7 Preliminary Concept 4a – Headland/groyne ...... 52 4.1.8 Preliminary Concept 4b - Headland/groyne + rubble access road...... 52 4.1.9 Preliminary Concept 4c - Headland/groyne + sand beach...... 52 5.0 EVALUATION OF PRELIMINARY ALTERNATIVE CONCEPTS ...... 53
5.1 Evaluation Criteria...... 53 5.1.1 Physical Criteria...... 54 5.1.2 Biological Criteria...... 54 5.1.3 Cultural and Socioeconomic Criteria...... 54 5.1.4 Technical and Engineering Criteria ...... 54 5.2 Public Evaluation of Preliminary Alternatives Concepts...... 58 5.3 Agency Evaluation of Preliminary Alternative Concepts...... 60 5.3.1 The “Do-Nothing” Alternative ...... 60 5.3.2 Preliminary Concept 1a – Headland Beach, Meadowcliffe Drive only...... 60 5.3.3 Preliminary Concept 1b – Headland Beach, bluff protection over full project site ...... 61 5.3.4 Preliminary Concept 2a – Groyne/headland beach, Meadowcliffe Drive only...... 61 5.3.5 Preliminary Concept 2b – Groyne/headland beach, bluff protection over full project site ...... 61 5.3.6 Preliminary Concept 3 – Breakwater and cobble beach...... 61 5.3.7 Preliminary Concept 4a – Headland/groyne ...... 62
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5.3.8 Preliminary Concept 4b - Headland/groyne and rubble access road ...... 62 5.3.9 Preliminary Concept 4c - Headland/groyne and sand beach...... 62 6.0 PREFERRED ALTERNATIVE ...... 63
6.1 Refinement of the Preferred Alternative ...... 63 6.2 Description of the Preferred Alternative ...... 64 7.0 ENVIRONMENTAL SCREENING OF PREFERRED ALTERNATIVE ...... 65
7.1 Detailed Environmental Analysis of the Preferred Alternative ...... 65 7.1.1 Physical Environment ...... 68 7.1.2 Biological Environment...... 71 7.1.3 Cultural Environment...... 72 7.1.4 Socioeconomic Environment ...... 73 7.1.5 Engineering/Technical...... 74 8.0 DESCRIPTION OF ALTERNATIVE CONSTRUCTION ACCESS...... 74
8.1 Alternative 1 – Bluffers Park Access Route...... 75 8.2 Alternative 2 – Marine Access Route ...... 76 8.3 Alternative 3 – Guild Inn Access Route...... 76 8.4 Alternative 4 – Bellamy Ravine Access Route...... 77 8.5 Alternative 5 – Top Dumping...... 78 9.0 EVALUATION OF ALTERNATIVE CONSTRUCTION ACCESS OPTIONS...... 78
9.1 Alternative 1 – Bluffers Park Access Route...... 79 9.2 Alternative 2 – Marine Access Route ...... 80 9.3 Alternative 3 – Guild Inn Access Route...... 81 9.4 Alternative 4 – Bellamy Ravine Access Route...... 81 9.5 Alternative 5 – Top Dumping...... 82 10.0 PREFERRED ACCESS ROUTE ...... 82
10.1 Public Comments on Preferred Construction Access Route ...... 82 10.1.1 Public Accessibility ...... 83 10.1.2 Guildwood Community Public Safety...... 83 10.1.3 Disturbance to Existing Vegetation and Wildlife...... 84 10.1.4 Noise...... 84 10.1.5 Vibration...... 85 10.1.6 Dust...... 85 11.0 SUMMARY OF PUBLIC CONSULTATION...... 85
11.1 Role of the Community Liaison Committee...... 85 11.2 Public Notifications and Consultation ...... 86 11.2.1 Notice of Intent...... 87 11.2.2 Community Liaison Committee Meeting #1 ...... 87 11.2.3 Community Liaison Committee Meeting #2 ...... 88 11.2.4 Public Meeting #1 ...... 89 11.2.5 Public Meeting #2 ...... 89 11.2.6 Meetings with the Guildwood Village Community Association...... 91 11.2.7 Notice of Filing...... 91 11.2.8 Notice of Project Approval...... 91 12.0 MONITORING PROGRAM ...... 91 13.0 REFERENCES ...... 92
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LIST OF FIGURES AND TABLES
FIGURE 1. GENERAL STUDY AREA...... 1 FIGURE 2. CLASS ENVIRONMENTAL ASSESSMENT PLANNING AND DESIGN PROCESS...... 3 FIGURE 3. OBLIQUE AERIAL PHOTO OF THE STUDY AREA...... 4 FIGURE 4. OBLIQUE AERIAL PHOTO OF THE STUDY AREA...... 4 FIGURE 5. VIEW OF BLUFF CREST AT 10 MEADOWCLIFFE DRIVE...... 5 FIGURE 6. GEOLOGICAL FORMATIONS FOUND AT THE PROJECT SITE...... 17 FIGURE 7. AREAS OF NATURAL AND SCIENTIFIC INTEREST...... 19 FIGURE 8. SCARBOROUGH BLUFFS SEQUENCE ESA #123...... 20 FIGURE 9. LOCATION OF STORM SEWER OUTFALL WITHIN BELLAMY RAVINE...... 22 FIGURE 10. LAKE ONTARIO WATER LEVELS FOR 2008-2009...... 23 FIGURE 11. LITTORAL CELL BOUNDARIES LOCATED ON THE TORONTO WATERFRONT...... 25 FIGURE 12. BOUNDARIES OF CLIFFCREST COMMUNITY...... 43 FIGURE 13. THE "DO - NOTHING" ALTERNATIVE DEPICTS THE POTENTIAL POSITION OF THE BLUFF TOE ...... 47 FIGURE 14. PRELIMINARY CONCEPT 1A - HEADLAND BEACH. MEADOWCLIFFE DRIVE ONLY...... 48 FIGURE 15. PRELIMINARY CONCEPT 1B - HEADLAND BEACH, BLUFF PROTECTION OVER FULL PROJECT SITE...... 49 FIGURE 16. PRELIMINARY CONCEPT 2A & 2B – GROYNE/HEADLAND BEACH...... 50 FIGURE 17. PRELIMINARY CONCEPT 3 - BREAKWATER + COBBLE BEACH ...... 51 FIGURE 18. PRELIMINARY CONCEPT 4A, 4B + 4C – HEADLAND/GROYNE + ADDITIONAL PROTECTION...... 53 FIGURE 19. RESULTS OF THE EVALUATION CRITERIA BY CATEGORY AS RANKED BY CLC MEMBERS …………...... 59 FIGURE 20. LTSSC POSITION IN RELATION TO PROPERTIES 1, 2 AND 10 MEADOWCLIFFE DRIVE...... 64 FIGURE 21. ALTERNATIVE 1 – BLUFFERS PARK ACCESS ROUTE...... 75 FIGURE 22. ALTERNATIVE 2 – MARINE ACCESS ROUTE...... 76 FIGURE 23. ALTERNATIVE 3 – GUILD INN ACCESS ROUTE...... 77 FIGURE 24. ALTERNATIVE 4 – BELLAMY RAVINE ACCESS ROUTE...... 78
TABLE 1. AIR QUALITY READINGS FOR EASTERN TORONTO (JULY 17, 2009)...... 20 TABLE 2. AIR QUALITY READINGS FOR EASTERN TORONTO (AUGUST 20, 2009)...... 21 TABLE 3. LAKE ONTARIO WATER LEVELS...... 23 TABLE 4. WATER LEVEL AND SET UP SUMMARY FOR LAKE ONTARIO AT TORONTO...... 24 TABLE 5. SEDIMENT SUPPLY RATES...... 26 TABLE 6. HISTORICAL WATER QUALITY MEASUREMENTS...... 27 TABLE 7. SEDIMENT QUALITY RESULTS...... 29 TABLE 8. FISH SPECIES COLLECTED ON THE SCARBOROUGH SHORELINE...... 31 TABLE 9. ADDITIONAL FISH SPECIES COLLECTED ON THE SCARBOROUGH SHORELINE...... 32 TABLE 10. FLORA SPECIES OF CONCERN...... 35 TABLE 11. BIRD SPECIES OBSERVED ON THE SCARBOROUGH SHORELINE...... 36 TABLE 12. RESULTS OF EVALUATION PRELIMINARY CONCEPTS...... 55 TABLE 13. RANKINGS OF PROPOSED EVALUATION CRITERIA...... 58 TABLE 14. DETAILED ENVIRONMENTAL ANALYSIS OF THE PREFERRED ALTERNATIVE...... 66
LIST OF APPENDICES
APPENDIX A EXISTING CONDITIONS
APPENDIX B DESIGN OF PREFERRED ALTERNATIVE
APPENDIX C PUBLIC CONSULTATION DOCUMENTATION
APPENDIX D DOCUMENTATION IN SUPPORT OF PROPOSED CONSTRUCTION ACCESS ROUTE
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1.0 INTRODUCTION
Toronto and Region Conservation Authority (TRCA) is proposing to carry out remedial erosion control work along a portion of the Lake Ontario shoreline, known here after as the Meadowcliffe Sector. The Meadowcliffe Sector is located at the base of the Scarborough Bluffs from Bellamy Ravine, also known as Gates Gully, westerly to East Beach at Bluffers Park in the City of Toronto (Figure 1). The study limits stretches approximately 1,400 metres (m) along the shoreline. The main area of erosion is concentrated along 600 m of the bluffs directly below Meadowcliffe Drive, approximately 57 m high with an average inclination of about 1.2:1 horizontal:vertical (h:v), where the shoreline is in direct contact with the bluff toe. The slope face is generally bare with some localized areas of sparse vegetation growing on the upper slope.
Figure 1. General Study Area. Source: TRCA, 2009.
The following Environmental Study Report (ESR) has been prepared as documentation of the decision-making approach exercised in determining the preferred measure for the proposed remedial work, and to establish that there are no negative impacts or outstanding concerns held by TRCA or reviewers associated with the proposed work.
1.1 Relationship of the Undertaking to the Environmental Assessment Act
TRCA is defined as a public body in Section 3 of Regulation 334/90 in the Environmental Assessment Act (R.S.O.) 1990, and as such, must conduct its remedial flood and erosion control projects in accordance with said Act.
1 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Recognizing that common elements exist in addressing flood and erosion problems, a coordinated approach to environmental assessments was developed by Conservation Ontario for all Conservation Authorities (CAs) known as the Class Environmental Assessment for Remedial and Erosion Control Projects (Class EA). According to the Class EA document:
“Remedial Flood and Erosion Control Projects refer to those projects undertaken by Conservation Authorities, which are required to protect human life and property, in previously developed areas, from an impending flood or erosion problem. Such projects do not include works which facilitate or anticipate development. Major flood and erosion control undertakings which do not suit this definition, such as multipurpose projects, lie outside the limits of this Class and require an Individual Environmental Assessment” (Conservation Ontario, 2002).
Twenty years of experience has demonstrated that using the Class EA approach for dealing with flood and erosion control projects is an effective way of complying with the Act requirements. Approval of the Class EA allows CAs to carry out these types of projects without applying for formal approval under the Act, on the condition that all other necessary federal and provincial approvals are obtained. A chart illustrating the key steps of the Class EA planning and design process is shown in Figure 2.
In addition to the Class EA process, TRCA recognizes that the project will require an environmental screening under the Canadian Environmental Assessment Act (CEAA). CEAA will be triggered in response to the potential environmental impacts that the project will produce pursuant to subsection 35(2) under the federal Fisheries Act and section 5(1) of the federal Navigable Waters Protection Act. Once the Class EA process is complete, the appropriate provincial and federal departments will be contacted: Fisheries and Oceans Canada (DFO), Environment Canada, Heritage Canada, Health Canada, Transport Canada and Natural Resources Canada. TRCA will prepare a Project Description for review by the selected Responsible Authority and the Canadian Environmental Assessment Agency to initiate the scope of the project, the scope of the assessment, and the scope of factors to be considered. TRCA will also contact other potentially interested agencies to ensure that all considerations are made in relation to the proposed undertaking.
2 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Figure 2. Class Environmental Assessment Planning and Design Process. Source: Conservation Ontario, 2002.
1.2 Purpose of the Undertaking
The objective of the Meadowcliffe Drive Erosion Control Project (the project), is to protect human life and property from the hazards of erosion and slope instability at the project site by providing long-term, low maintenance protection which is compatible with the surrounding physical, biological, social and cultural environment.
1.3 Site Description
The current project limits is located along the base of the Scarborough Bluffs and comprises of approximately 1,400 metres (m) of shoreline extending from Bellamy Ravine, also known as Gates Gully, westerly to East Beach at Bluffers Park. Roughly half of the tableland in this sector is dedicated greenspace within Cudia Park, west of Meadowcliffe Drive and east of Lakehill Crescent. The remaining tableland at Meadowcliffe Drive and Lakehill Crescent is privately owned with 16 residential properties backing onto the bluffs. The 600 m of bluffs directly below Meadowcliffe Drive are approximately 57 m high with an average inclination of about 1.2:1 h:v, where the shoreline is in direct contact with the bluff toe. The upper 8 to 10 m of the bluffs has an inclination of 0.7:1 to 1.4:1 h:v and consists of permeable subsoil layers that promote formation of temporary perched groundwater following rainfall or snow melt events. The slope 3 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
face is generally bare with some localized areas of sparse vegetation growing on the upper slope. Representative photographs of the study area are shown in Figure 3 to Figure 5.
Figure 3. Oblique aerial photo of the study area. Source: TRCA, 2006.
Figure 4. Oblique aerial photo of the study area. Source: TRCA, 2006.
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Figure 5. View of bluff crest at 10 Meadowcliffe Drive. Source: TRCA, 2007.
1.4 General Description of the Undertaking
There are four situations in which remedial flood and erosion control projects may be undertaken within the Class EA: I) Riverine Flooding II) Riverine and Valley Slope Erosion III) Shoreline Flooding IV) Shoreline Erosion
The primary objective of the project is to provide long-term protection against (IV) shoreline erosion. Alternative remedial measures to address this problem situation include: • Reducing wave energy and enhancing natural processes; • Protecting the shore from wave energy; and • Stabilizing slopes through drainage or grading improvements.
Secondary objectives include the protection of existing land uses, improved aesthetics, and improved aquatic and terrestrial habitat. The project will examine a number of alternatives to achieve the primary and secondary objectives outlined in the Class EA document, including: • Headland beach • Headland beach and boulder berm • Offshore breakwaters plus headland beach • Groyne retained sand beach
In accordance with the Class EA planning process, a full range of alternatives must be developed, including both traditional and innovative approaches. The type and range of alternatives developed, such as the ones listed above, will vary by project as they are based on 5 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
the nature, cause and extent of the problem, and must be tailored to the individual characteristics of each site.
The decision making approach used in the selection of the preferred remedial action is documented in detail in Section 5.0.
In determining the preferred measure to remediate the erosion and slope instability problem, two major factors were considered: risk to structure(s); and the cause of the hazard. According to TRCA’s Design Criteria, potential risk to existing structures is deemed to be the most important factor and accordingly is given more weight than the physical and geological condition associated with the cause of erosion and/or instability.
In all cases, the design of erosion control and slope stabilization works must provide protection compatible with TRCA’s Design Criteria, which includes improvements to or enhancements of aquatic and terrestrial habitat conditions through natural designs.
Based on the outcome of the Class EA process for this project, the proposed remedial action (the undertaking) consists of a cobble beach retained by four headlands. The preferred solution also considers the potential need for a buttress at the base of the bluffs at the east end of the shoreline sector to reduce slope recession.
The decision-making approach used in selecting this as the preferred remedial action is documented in detail in Section 5.0 of this report. The proposed undertaking meets all TRCA planning and policy objectives, and satisfies the needs and concerns of the affected property owners and general public.
1.5 Rationale for the Undertaking
For several decades TRCA has monitored the rate of erosion along the crest of the Scarborough Bluffs in relation to permanent structures (e.g. residential dwellings), mainly on private residential properties. The acceleration of the erosion rate observed along the Meadowcliffe Sector through TRCA’s annual erosion monitoring, prompted TRCA to retain a geotechnical consulting firm to conduct a review of slope stability and erosion in 2006. The results of this geotechnical review determined that the upper 30 m of the bluff face is expected to recede to a stable inclination of 1.5:1 (h:v), while the lower section of the bluff is expected to reach a shallower inclination of 2.5:1 (h:v) in the long-term. The report also notes that the long- term stable slope crest (LTSSC) is influenced by the position of slope toe which is subject to recession caused by active wave erosion of the slope toe. The LTSSC is the position on the tableland adjacent to the subject slope that represents the application of setbacks for both the toe erosion allowance and slope stability components. Based on these analyses, Terraprobe calculated the stability setbacks from the existing slope crest, assuming that toe protection is in place, and determined that three residential dwellings could become be at risk and affected by slope instability and erosion in the long-term if stabilization and protection works were not carried out.
Shoreplan’s analysis suggests that as the shoreline erodes the fillet beach located east of Bluffers Park will continue its eastward growth, gradually protecting the toe of the bluffs as it expands until the beach provides full protection against wave induced toe erosion. Based on this prediction and an average recession of the bluff toe at a rate of 1.2 m per year, it estimated that numerous residential properties on both Meadowcliffe Drive and Lakehill Crescent, as shown in Figure 13, will be impacted by erosion and slope recession.
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TRCA remedial erosion control works are carried out within the context of a comprehensive plan which balances the various resource management and ecological benefits of these works with public access and related issues, and are further analyzed on the basis of financial cost/benefit. In accordance with the Class EA process, it must also be demonstrated that the proposed action falls within the scope of TRCAs watershed plan and is consistent with policies and appropriate programs within which the proposed project may be considered to be a part.
The primary properties affected by slope instability and erosion within the study area include private residences. Due to the location of these properties and their view of Lake Ontario, many of these properties have considerable market value. There are twelve (12) properties along Meadowcliffe Drive, as well as several homes on Lakehill Crescent that are potentially impacted due to long-term issues arising from erosion and slope instability. Current market value of these homes is estimated in the millions. The residence known as “Fool’s Paradise” located at 1 Meadowcliffe Drive, designated as a heritage site by Ontario Heritage Trust, is also at risk. It would be difficult to put a monetary value on this property, as it was donated by Doris McCarthy, a Canadian artist, to be used as an area for heritage and artist activities.
Prior to making a decision to proceed with a remedial action at this location TRCA had to consider the impact of a “Do-Nothing” approach, as well as the feasibility of employing another Conservation Authority program such as land acquisition. Considering the potential risk to life and property that would result if a “Do-Nothing” approach was taken as well as the potential cost to purchase the affected properties, TRCA made the determination to proceed with a Class Environmental Assessment for Remedial and Erosion Control Projects.
2.0 BACKGROUND
2.1 History of the Problem
TRCA staff has been monitoring erosion rates on Meadowcliffe Drive since 1985 at the request of several homeowners who expressed concern over the loss of property and the potential long-term risk to their homes.
In 1996, TRCA prepared the Integrated Shoreline Management Plan (ISMP) to provide a more detailed understanding of the shoreline ecosystem within the boundaries of Tommy Thompson Park and Frenchman’s Bay, and to provide the necessary framework for TRCA and local municipalities to establish priorities for future initiatives and for evaluating site-specific shoreline works, protection of natural features, lakefilling, habitat protection and regeneration, private development and public recreation activities.
The ISMP states that the Meadowcliffe Drive shoreline should remain in a natural state because it represents one of the few unprotected and natural shores of the Scarborough Bluffs. It is recommended in the ISMP that nearshore armouring with boulder placement be considered on an experimental basis in an attempt to restore the condition of the shore prior to the 1800s, improve informal access along the shoreline and improve local fish habitat. It was noted, however, that the change to the shoreline would be a very gradual one and that erosion would not be eliminated. Based on the recommendations in the ISMP, TRCA continued to monitor the rate of erosion along Meadowcliffe Drive and did not pursue any shoreline stabilization options.
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In 2001, after a period of active erosion, TRCA commissioned Terraprobe Limited to carry out a geotechnical review of slope stability and erosion along the Lake Ontario shoreline immediately below Meadowcliffe Drive. This study included a review of historical air photos, soil and groundwater conditions, erosion processes and rates, a detailed slope stability analysis, coastal engineering review and recommended erosion protection.
In their final report dated November 27, 2001, Terraprobe provided calculations of slope crest erosion rates between 1991 and 2001 and determined that localized crest loss ranged from 6 to 12 metres at the west part of the study area, to about 2 to 3.5 metres at the east part of the study area. Noting that the erosion was primarily the result of toe erosion by wave action and surface run-off flowing over the slope crest, the following recommendations were made:
• A significant upgrade of the stormwater collection system along the Meadowclife Drive right-of-way; • Connection of existing roof eavestroughs to the street storm sewer; • Construction of small earth berms along the slope crest; • Placing boulders near the shore on an experimental basis, as recommended in the ISMP; and • Planting/seeding along the gullies and on bare slope areas.
Terraprobe also recommended further studies including:
• Continued monitoring of the slope crest on an annual or bi-annual basis; and • A stormwater management assessment of the area to determine the quantities of surface runoff over the slope crest.
Following the release of the 2001 Terraprobe report, staff continued to monitor the slope crest on an annual basis and the City of Toronto commissioned Winter Burnside to carry out a storm drainage study for the Meadowcliffe Drive area. The final Winter Burnside report in 2002 resulted in several upgrades being carried out by the City of Toronto in 2004. It is understood that these improvements included depression storage, enhanced ditches and storm sewers, and a landscaping component.
In the spring of 2005, slides occurred along several sections of the Scarborough Bluffs. Numerous homeowners on Meadowcliffe Drive expressed concern to Councillor Ashton’s office over the amount of property lost to erosion in a single year and requested that remedial action be taken. In response to the residents’ concerns, TRCA commissioned Terraprobe to re- assess the site and slope conditions and compare these findings to their 2001 report, and to provide recommendations on slope and shoreline stabilization works.
As part of this study, detailed measurements of the slope crest position were taken relative to the existing structures and features at each of the 12 residential properties. Based on Terraprobe’s measurements, slope crest recession rates ranged from 0.04 to 2.14 m per year between 2000 and 2005. Toe erosion rates were inferred through a comparison of the shoreline positions available on maps of air photos from 1980, 1991, 2002 and 2005. As a general trend, localized deepening of the lakebed topography was also noted in the order of 0.2 to 0.3 m and may be attributed to ongoing erosion and recession of the toe. It was also noted that the potential for waves to uprush and erode the slope toe increases with the deepening of the lakebed.
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Based on the 2005 slope stability analysis, the LTSSC is projected to move inland by approximately 48 m from the 2005 slope crest. This LTSSC was determined with the assumption that there would be no further erosion at the toe of the bluffs. It should be noted however, that wave action continues to erode the exposed toe, and the LTSSC will continue to move further inland as the toe continues to recede. The final report, dated April 26, 2006, illustrates the long-term risk to the Meadowcliffe properties by providing minimum distance from each property to the LTSSC, which concluded at least 5 houses are between 0 and 10 m from the LTSSC and several others are within 25 metres of this projected slope crest. Also within the LTSSC is the easternmost portion of the roadway and stormwater collection drains. Based on the significant recession of the slope toe and respective recession of the LTSSC, Terraprobe strongly recommended that shoreline works be implemented.
In May 2006, staff attended a public meeting hosted by Councillor Ashton for the Meadowcliffe Drive residents. The purpose of the meeting was to present the findings in the 2006 Terraprobe report and to give the property owners an opportunity to voice their concerns in an open forum. At the meeting the public requested that action be taken to provide long-term protection for the shoreline and TRCA received a letter shortly thereafter from Councillor Ashton in support of this initiative.
Based on the significant change in recession rates, and the support of Councillor Brian Ashton and the Meadowcliffe community for immediate action, TRCA received internal approval to investigate a broader range of alternatives than described in the ISMP, and that these options be evaluated through the Class EA process. The study area was expanded beyond Meadowcliffe Drive to include all of the unprotected shoreline between Bellamy Ravine and the East Beach at Bluffers Park in order to gain a thorough understanding of the coastal processes affecting the site, and to ensure that the alternative options consider impacts to natural heritage, public access and public safety.
2.2 Identification of Previous Studies
2.2.1 Geotechnical Reports
TRCA has also commissioned studies to develop a range of shoreline protection works that could be used along the Meadowcliffe Sector. As a component of the Class EA, TRCA developed a geotechnical assessment along the bluffs based on a review of the following reports:
• Geocon Inc. 1982. Erosion Control Study, Stage 2, Scarborough Bluffs. • Golder Associates Ltd. 1990. Subsurface Investigation, Meadowcliffe Drive Sewer Works and Storm Sewer Outfall to Bellamy Ravine. • Geocon Inc. 1996. Slope Stability Study, Meadowcliffe Drive. • Terraprobe Ltd. 2001. Geotechnical Investigation and Slope Stability Assessment, Meadowclife Drive. • Terraprobe Ltd. 2006. Geotechnical Review of Slope Stability and Erosion, Meadowclife Drive, Scarborough Bluffs, Toronto. • Terraprobe Ltd. 2009. Geotechnical Review of Slope Stability and Erosion Stabilization Options, Meadowclife Drive, Scarborough Bluffs, Toronto. • Winter Burnside. 2002. Meadowcliffe Drive Area Storm Drainage Study for City of Toronto.
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The assessment of the historical geotechnical reports helped determine the LTSSC, the most recent 2005 slope toe position indicated the residential dwellings at Nos. 2, 10 and 42, including a shed at the residential property No. 10 are all within the LTSSC. These dwellings have the potential to become unsafe and affected by the slope instability and erosion. As a result the need for a Class Environmental Assessment to examine shoreline protection works along the Meadowcliffe Drive Sector was identified.
Copies of these technical reports are available for review at TRCA, 1 Eastville Avenue, Toronto.
2.2.2 Planning Documents
The study area has received extensive scrutiny at all levels of government as part of the Toronto Waterfront planning process. In developing the range of alternatives for evaluation under the Class EA guidelines, TRCA utilized and incorporated many of the planning recommendations from the municipal, provincial and federal governments.
Metropolitan Waterfront Plan (1994) In 1994, a revised vision of the Toronto Waterfront was developed by the City of Toronto to achieve a waterfront that is “healthy, vibrant and publicly accessible, through responsible stewardship, and strong partnerships between government and the community”. The Plan laid out many policies, some of which are general in nature and others that specifically refer to the Scarborough bluffs. A summary of the most pertinent policies in this plan are provided below:
3) to undertake the protection and enhancement of the following significant natural areas in cooperation with the MTRCA, area municipalities, other appropriate agencies and the community: a) terrestrial habitats within: ii) Scarborough Bluff area;
22) to oppose the creation of additional land or permanent structures in Lake Ontario through lakefilling or dredging, except for recreational or essential public works which comply with the other applicable policies of the Plan and that both demonstrably contribute to the healthy functioning of coastal and biological processes and provide public benefits as determined by Council in consultation with other responsible agencies by a) improving water quality; b) enhancing or creating aquatic habitat; and c) providing public access to the water’s edge.
24) to maintain and restore within the Waterfront Environmental Impact Zone (WEIZ) a diversity of terrestrial and aquatic habitats and connecting links between habitats as part of a comprehensive strategy that includes:
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a) the conservation, enhancement and management of terrestrial ecosystems on unstable slopes and flood- susceptible, where feasible; b) the use of natural techniques for remediating problems associated with hazard lands, where feasible; c) initiatives to establish aquatic habitats where such initiatives do not negatively alter the pattern of coastal processes; and d) the regulation by respective levels of government of all activities that alter the land form or lakebed including excavations, dredging and the placement of fill.
25) to support the development and administration of a Shoreline Management Plan for the Metropolitan Waterfront by the MTRCA in cooperation with other public agencies.
68) to protect and enhance the significance of the Scarborough Bluffs area by: a) allowing natural processes, such as regeneration and erosion, to occur where feasible.
TRCA is committed to the City of Toronto’s vision of a healthy waterfront. TRCA will work to ensure that these policies are considered throughout the planning, study and implementation phases of the Meadowcliffe Drive Erosion Control Project.
Royal Commission on the Future of the Toronto Waterfront (1990) In 1988, the Royal Commission on the future of the Toronto Waterfront was initiated as a federal inquiry to:
“Make recommendations regarding the future of the Toronto Waterfront, and to seek the Concurrence of affected authorities in such recommendations, in order to ensure that, in the public interest, federal lands and jurisdiction serve to enhance the physical, environmental, legislative and administrative context governing the use, enjoyment and development of the Toronto Waterfront and related lands” (Royal Commission, 1990).
Recommendations were based on nine guiding principles for the future of Toronto Waterfront: clean, green, usable, diverse, open, accessible, connected, affordable, and attractive.
Lake Ontario Greenway Strategy (1995) The Lake Ontario Greenway Strategy was developed by the Waterfront Regeneration Trust in fulfillment of its mandate to coordinate the programs and policies of the Province and agencies related to the waterfront, and to facilitate the establishment of a waterfront trail. The vision the Strategy calls for a waterfront that is clean, green, accessible, connected, open, usable, diverse, affordable and attractive. To achieve this vision, the Strategy summarizes a number of goals and objectives that include:
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1) Protect the physical, natural and cultural attributes associated with the Lake Ontario Greenway; 2) Identify restoration needs and methods and encourage landowners, communities and agencies to undertake regeneration activities. 3) Promote greater awareness and understanding and recreational use of the waterfront and encourage community pride and participation in its regeneration. 4) Promote economic activities and employment on the waterfront that are compatible with other Greenway objectives. 5) Foster cooperation in cost-effective public and private initiatives by reducing jurisdictional gridlock, sharing resources, and coordinating waterfront activities.
The Meadowcliffe Drive Erosion Control Project incorporates the objectives of the Lake Ontario Greenway Strategy to ensure that all alternatives comply with provincial interests and policies.
Integrated Shoreline Management Plan: Tommy Thompson Park to Frenchman’s Bay (1996) The Integrated Shoreline Management Plan (ISMP) was developed by TRCA following a recommendation put forth in the Lake Ontario Greenway Strategy in 1995. The goal of the ISMP is:
“…to provide an ecosystem-based framework to ensure that shoreline management activities result in a clean, green, accessible, diverse, connected, open, affordable, attractive and useable waterfront from Tommy Thompson Park to Frenchman’s Bay” (TRCA, 1996).
As previously noted, the ISMP reported that the Meadowcliffe Drive shoreline should remain in a natural state because it represents one of the few unprotected and natural shores of the Scarborough Bluffs. It is recommended in the ISMP that nearshore armouring with boulder placement be considered on an experimental basis in an attempt to restore the condition of the shore prior to the 1800s, improve informal access along the shoreline and improve local fish habitat. It was noted, however, that the change to the shoreline would be a very gradual one and that erosion would not be eliminated. Based on the recommendations in the ISMP, TRCA continued to monitor the rate of erosion along Meadowcliffe Drive and did not pursue any shoreline stabilization options.
2.2.3 Aquatic and Terrestrial Habitat Reports
The aquatic and terrestrial conditions along the Toronto Waterfront have undergone intensive scrutiny during the last thirty years. The collapse of native fish stocks, turbid, odorous and polluted water, reductions in waterfowl populations, sediment contamination, a scarcity of public waterfront access, massive algal blooms, increases in invasive wildlife and plant species, and large-scale decline in fish populations are demonstrative of the effects of urbanization.
During the mid-1980s, studies were conducted by the Toronto Remedial Action Plan (RAP) to specifically identify sources of degradation along the Toronto Waterfront and to provide targets and recommendations to improve these conditions. Since the 1980s, the Toronto RAP has 12 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
continued to fund projects aimed to improve the Toronto Waterfront, continued to monitor lake health to quantify improvements in overall habitat quality and assess the success of remediation efforts.
This Class EA incorporates a number of studies compiled over the last thirty years in order to provide a temporal understanding of the environmental conditions along the Meadowcliffe Drive Sector. These reports include:
• Environment Canada, Ministry of the Environment, Ministry of Natural Resources, Toronto and Region Conservation Authority.1989. Metro Toronto and Region Remedial Action Plan. Stage 1. Environmental Conditions and Problem Definition. • Environment Canada, Canadian Wildlife Service, Blokpoel, H. and Tessier, G.D. 1991. Distribution and Abundance of Colonial Waterbirds Nesting in the Canadian Portions of the Lower Great Lakes System in 1990, Technical Report Series No. 117. • Metropolitan Toronto Planning Department, Research and Special Studies Department Division. 1995. State of the Environment Report: Metropolitan Toronto. • Ministry of the Environment.1985. Historical Development and Quality of the Toronto Waterfront Sediments - Part I. • Ministry of Natural Resources (MNR). 1974. Operation Doorstop Angling: Metropolitan Toronto Fishery Project Report - Volume One. • Ministry of Natural Resources (MNR). 1989. Fish Community and Aquatic Habitat of the Toronto Waterfront. • Ministry of Natural Resources. 1994. 1989 - 1993 Toronto Waterfront Fish Communities: Summary and Assessment. • Shoreline Management Work Group for the Waterfront Regeneration Trust. 1996. Shore Management Opportunities for the Lake Ontario Greenway. • Toronto and Region Conservation Authority (TRCA). 1996. Integrated Shoreline Management Plan: Tommy Thompson Park to Frenchman’s Bay. • Toronto and Region Conservation Authority (TRCA). 2000. Toronto Waterfront Fisheries Communities. • Toronto and Region Conservation Authority (TRCA). 1982. Environmentally Significant Areas Study. • Waterfront Regeneration Trust. 1987. Toronto Eastern Waterfront Summary: A Report for the Toronto Remedial Action Plan Work Team. Beak Consultants Ltd. • Waterfront Regeneration Trust. 1995. Lake Ontario Greenway Strategy. • Waterfront Regeneration Trust. 1995. Lake Ontario Greenway Strategy, Next Steps. • Waterfront Regeneration Trust. 2002. Clean Waters, Healthy Habitats: Progress Report 2001 Technical Edition - Toronto and Region Remedial Action Plan.
Terrestrial and aquatic data was obtained by TRCA. Data from these inventories are referenced in this report where applicable.
2.2.4 Socioeconomic and Cultural Heritage Studies
The following sources of information were used to define the socioeconomic conditions and cultural heritage resources for the Study Area:
• City of Toronto website. 2001 and 2006. Cliffcrest Neighbourhood Profile. (www.toronto. ca/demographics /cns _ profiles/cns123.htm). • Guildwood Village Community Association (GVCA) website. 2009. (www.guildwood. on.ca). 13 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
• Ontario Heritage Trust website. 2009. Provincial Plaque Unveiling Commemorates Fool’s Paradise – Home and Studio of Renowned Artist Doris McCarthy. (www.heritagefdn.on.ca/ userfiles/ HTML/nts_1_8214_1.html). • Roots, B., Chant, D.A. and Heidenreich, C.1999. Special Places: The Changing Ecosystems of the Toronto Region. • Toronto Neighbourhoods website. 2009. Cliffcrest. (www.torontoneighbourhoods. net/regions/ scarborough). • Toronto Transit Commission (TTC) website. 2009. Bus Routes, 86 Scarborough. (www.ttc.on.ca). • Waterfront Regeneration Trust. 1995. Lake Ontario Waterfront Experiences. • Waterfront Regeneration Trust. 1995. The Waterfront Trail.
2.3 Justification of Conservation Authority Involvement
TRCA has a mandate to carry out remedial erosion control works as set out in Section 20 of the Conservation Authorities Act (R.S.O. 1990):
“The objects of an authority are to establish and undertake, in the area which it has jurisdiction, a program designed to further the conservation, restoration, development and management of natural resources other than gas, oil, coal and minerals (R.S.O. 1990, C.27, s.20).”
As part of this broad mandate, CAs are considered to have prime responsibility over water management in terms of water quantity and related hazards through administrative and regulatory powers. In the 1980 Watershed Plan, TRCA developed and implemented its Erosion and Sediment Control Program (ESCP) with two major directions:
“To minimize the aggravation or creation of erosion or sediment problems as a result of new development, and to rectify existing problems through protective works” (TRCA, 1980).
These directions are categorized as either preventative, or protective, respectively. The project falls under the protection component of the ESCP, which is designed to protect lives and minimize loss of property through the construction of suitable remedial works. Through annual capital funding from the City of Toronto, TRCA is able to implement a program or major remedial works for shoreline protection and slope stabilization throughout the watersheds within the City of Toronto. The goal of TRCA through this project is to prevent, eliminate or reduce the risk of hazard to life and property, and to protect and enhance the natural attributes along the Lake Ontario shoreline and the primary river valleys within Toronto.
The results of the geotechnical assessment carried out by Terraprobe (2006) as described in Section 2.2 indicates that erosion and slope instability will likely continue at the site, resulting in the further loss of property at the top of the crest, which will eventually affect the residential dwellings located on Meadowcliffe Drive if remedial action is not taken.
3.0 BASELINE ENVIRONMENTAL INVENTORY
Once the determination has been made that remedial works are warranted at a given site, a baseline inventory is prepared. TRCA has developed the following baseline inventory of the
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existing conditions of the Meadowcliffe Drive shoreline and surrounding environments. The baseline environmental inventory provides the information required to evaluate the alternative methods, and the forms of the baseline from which the preferred alternative will be compared to determine its effectiveness, as well as its environmental impact.
The inventory involves the examination and documentation of:
• the erosion problem; • existing site conditions, including physical, biological, cultural and socioeconomic characteristics; • engineering/technical aspects to be considered; and • previous protective measures that have been implemented within the study area.
This baseline environmental inventory takes into consideration the directly and indirectly affected environment. The indirect area affected by the project includes the entire littoral cell and associated shorelands. This indirect area is referred to as the regional study area. The area directly affected by the project is referred to as the study area or project site.
Baseline environmental data was collected from the following organizations due to their specific expertise relevant to the regional and local study area:
• Fisheries and Oceans Canada • Environment Canada • Ontario Ministry of Natural Resources • Ontario Ministry of the Environment • City of Toronto, Toronto Water • Waterfront Regeneration Trust • Toronto Field Naturalists • Toronto Ornithological Club
To assist with the review and expansion of the baseline inventory, as well as the design of the preferred alternative, TRCA retained the services of the coastal engineering firm Shoreplan Engineering Limited in 2006.
Several groups were contacted for their input into the inventory process. This included local landowners, community groups such as the Guildwood Village Community Association, Ontario Heritage Trust and local Councillor Brian Ashton (Cliffcrest Community) and Councillor Paul Ainslie (Guildwood Community).
3.1 Location
The project site encompasses a section of Lake Ontario shoreline on the lakeward side of the Scarborough Bluffs in the City of Toronto. This shoreline sector measures 1,400 m and is located between the eastern beach of Bluffers Park and Bellamy Ravine (also known as Gates Gully). The tableland adjacent to the shoreline includes dedicated greenspace, as well as 16 residential properties that back directly onto the bluffs.
Shoreline Reach: Meadowcliffe Drive Sector Site Location: City of Toronto (former City of Scarborough)
Landowners: TRCA, City of Toronto, Ontario Heritage Trust and private landowners all
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own the land, while the Ministry of Natural Resources owns the waterlot. Easting: 643613 Northing: 48442809 Latitude: 43.72 N Longitude: 79.23 W UTM: 432423 Topo Map No.: 30M/11 Chart No.: 2085
3.2 Existing Site Conditions
In accordance with the Class EA process, the broad definition of ‘environment’, as provided in the Environmental Assessment Act, is applied to this section. The prepared environmental description is “an inventory of elements for which a given project is likely to have an impact” (Conservation Ontario, 1993). The inventory includes an evaluation of the presence and extent of physical, biological, cultural, social, economic, and technical engineering elements applicable to the study area.
3.2.1 Physical Environment
Unique Landforms Next to Niagara Falls, the Scarborough Bluffs are considered by many as Ontario’s most extraordinary natural feature, and have been studied in detail over the years due to the geological insight they provide regarding past glacial events and climatic conditions. The Scarborough Bluffs extend from Victoria Park Avenue to Highland Creek for approximately 20 kilometers (km) along the Toronto waterfront. Sedimentary deposition formed the Scarborough Bluffs over the last 100,000 years. The bluffs range between 50 to 85 m above lake level. The bluffs are internationally recognized as an important heritage resource that is unique to Toronto.
The oldest and most dominant earth science feature is located near the base of the Bluffs. This feature is composed of deltaic clays, silts, and sands, which are known as the Scarborough Formation. It is divided into two separate layers: the overlying Scarborough Sand Formation and the underlying Scarborough Clay Formation. The Scarborough Sand Formation represents one of two aquifers systems along the Scarborough waterfront and the second provides an impermeable layer underneath the Scarborough Sand (Eden and Eyles, 2002).
The Sunnybrook Till is the second major sedimentary formation making up the Scarborough Bluffs, and is perched on top of the Scarborough Formation. This till deposit typically ranges from 8 to 12 m in depth and is fine-grained in texture ranging from silt to silty-clay till. However, some controversy exists as to the nature of the Sunnybrook formation as to whether it is glaciolacustrian or strictly glacial in nature. Regardless, this formation acts as an aquatard with high impermeability, low plasticity and a hard consistency.
Overlying the Sunnybrook Till is the Lower Leaside Till which consists of silty sand till with clay and traces of gravel. This formation is very stiff to hard in consistency. It does, however provide the second water table associated with the Scarborough Bluffs, located at the transition with the more impermeable silts and clays located in the Sunnybrook Till.
A Middle Wisconsinan deposit is found at Cathedral Bluffs Park, which is represented by the Thorncliffe Formation, Seminary Till, and Meadowcliffe Till. Further east at Cudia Park, Early Wisconsinan and Middle Wisconsinan deposits are found beneath Late Wisconsinan Glacial Lake Iroquois silts (Eden and Eyles, 2002). A glacial Lake Iroquois Bluff is also visible at Cudia Park. 16 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Figure 6. Geological formations found at the project site. Source: Eden and Eyles, 2002.
The average height of the bluffs along the Meadowcliffe Sector is approximately 57 m with an average inclination of about 1.2:1 (horizontal: vertical). The slope face is generally bare of vegetation with some localized areas of sparse vegetation on the upper edge of the slope. The shoreline in this waterfront sector is located at toe of the bluff. TRCA staff has been monitoring erosion rates on Meadowcliffe Drive since 1985 at the request of several homeowners who have expressed concern over the loss of property and the potential long-term risk to their homes.
To the east of the study area the Bellamy Ravine shoreline sector has a bluff face that is vegetated with a mixture of herbaceous plants, shrubs, and deciduous trees. The deep stream gullies are vegetated with a mixture of birch, poplar, cherry, maple, oak, hawthorne and willow while the steep cliffs remain bare.
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Existing Mineral / Aggregate Resource Extraction Industries There were no existing mineral/aggregate resource extraction industries located within the study area. However, from the 1830's to the First World War, the near shore area along the Scarborough Bluffs was the site of a unique "stone hooking" industry. A “stone hooker” was a shallow draft schooner that could work close to the shore, enabling crews to pick the large shale slabs from the lakebed. Several men working together would use poles with bent forks on the end to lift up a slab from the bottom and then maneuver it onto a floating raft towed behind the ship. This material was used for ballast and would be later sold for construction activities. By the 1830s, up to 43,000 tonnes of boulders were hooked on an annual basis. Stone hooking is believed to have accelerated shoreline erosion along the Lake Ontario shoreline. In 1857, a law was passed prohibiting stone hooking within 15 m of shore (TRCA, 2006).
Given the extent of the glacial deposits along the Scarborough Bluffs, the study area may be viewed by the aggregate resource extraction industry as a potential resource location. The Scarborough Bluffs however occupied by many well-established residential communities within the City of Toronto and would therefore be unlikely location for aggregate resource extraction within the foreseeable future.
Area of Natural and Scientific Interest – Earth Science (ANSI-ES) The Ontario Ministry of Natural Resources (OMNR) selected three representative Areas of Natural and Scientific Interest (ANSI) to depict the range of geological conditions along the Scarborough Bluffs. To be classified as ANSIs, the following notable features have been identified by the MNR:
“At their highest point, the Scarborough Bluffs rise 110 m above the level of Lake Ontario. Located in the Borough of Scarborough, these bluffs display the Pleistocene sequence of deposition in Ontario. The Scarborough Bluffs are the highest and most continuous stretch of shoreline cliffs in Site District 7 – 4. They also represent a unique example of cliffs in Canada.” (OMNR, 1984).
Only one (1) of the three (3) areas to represent the geological history of the Scarborough Bluffs is located in our study area, known as Cudia Park. This area demonstrates Early Wisconsinan, Scarborough Formation and Sunnybrook Till, Middle Wisconsinan, Thorncliffe Formation (lower and middle), Seminary Till, Meadowcliffe Till overlain by Late Wisconsinan, and Lake Iroquois sediment (OMNR, 1998). The Scarborough Bluffs provide scientist with insight to North America’s recent geologically history, and act as an important scenic, recreational and cultural resource for the City of Toronto.
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Figure 7. Areas of Natural and Scientific Interest. Source: TRCA, 2009.
Specialty Crop Areas / Agricultural Lands or Production The Meadowcliffe Drive, Cudia Park section of the Scarborough shoreline is located within an urban, residential area. As such, no specialty crop areas or agricultural lands are involved in the study area.
Niagara Escarpment / Oak Ridges Moraine This section of shoreline is not located in the Niagara Escarpment or the Oak Ridges Moraine.
Environmentally Sensitive / Significant Areas (Physical) The Environmental Sensitive Area (ESA) classified as ESA #123 (Scarborough Bluffs Sequence) is located along the western portion of the project area from Cudia Park westward (Figure 8). The Scarborough Bluffs Sequence ESA was selected to represent the geological features found along the Scarborough Bluffs. To be classified as an ESA, Criterion 1 was fulfilled.
The Scarborough Bluffs Sequence exhibits the most complete and interesting record of Pleistocene geology in North America, if not the world. This Sequence shows evidence of Seminary Till which has not been found to extend inland, and is one of the last areas in the region where the Lake Iroquois shoreline (12,000 years B.P.) can be observed. This Sequence also contains the Type Section for the Meadowcliffe Till (MTRCA, 1982).
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Figure 8. Scarborough Bluffs Sequence ESA #123. Source: TRCA, 2009.
Air Quality The study area is located to the east of Toronto’s downtown core. The project area experiences similar air quality conditions found throughout the Toronto region as a result of urbanization and industrial development in Southern Ontario. Atmospheric pollutants that are sampled on an hourly basis in the Toronto area include carbon monoxide (CO), nitrogen dioxide (NO2), ground level ozone (O3), sulphur dioxide (SO2), and suspended particulates and total reduced sulphur compounds. Typically, most air pollutants have decreased in concentration or remained relatively stable since the late 1960’s (TRCA, 2004).
The Air Quality Index (AQI) is an indicator of air quality, based on hourly pollutant measurements of some or all of the six most common air pollutants listed above and is used to inform Toronto residents of the existing air quality and to provide health advisories when the combined levels of the pollutants exceed certain levels of the index (MOE, 2009). If the air quality value is below 32, the air quality is considered relatively good. If the AQI value is in the range of 32 to 49 (moderate category), there may be some adverse effects on very sensitive people. An index value in the 50 to 99 range (poor category), may have some short-term adverse effects on the human or animal populations, or may cause significant damage to vegetation and property. An AQI value of 100 or more (very poor category) may cause adverse effects on a large proportion of those exposed (MOE, 2009).
Elevated air temperatures during the summer are related to increased air quality index advisories and warnings may be issued for up to several weeks at a time depending on weather conditions. Overall, air quality in Toronto is below National Ambient Air Quality Objectives (MOE, 2009). Below are two examples of testing during spring and summer months. The AQI ratings in July are much lower than the ratings in August and are typical to what is found during these months.
Table 1. Air Quality Readings for Eastern Toronto (July 17, 2009). Air Quality for TORONTO EAST Date Time AQI Cause 17-July-09 12:00 AM 11 Ozone (O3) 17-July-09 1:00 AM 11 Fine Particulate Matter (PM2.5) 20 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Air Quality for TORONTO EAST Date Time AQI Cause 17-July-09 2:00 AM 11 Fine Particulate Matter (PM2.5) 17-July-09 3:00 AM 14 Ozone (O3) 17-July-09 4:00 AM 16 Ozone (O3) 17-July-09 5:00 AM 12 Ozone (O3) 17-July-09 6:00 AM 9 Ozone (O3) 17-July-09 7:00 AM 10 Fine Particulate Matter (PM2.5) 17-July-09 8:00 AM 11 Fine Particulate Matter (PM2.5) 17-July-09 9:00 AM 10 Ozone (O3) 17-July-09 10:00 AM 14 Ozone (O3) 17-July-09 11:00 AM 19 Ozone (O3) 17-July-09 12:00 PM 21 Ozone (O3) Source: MOE, 2009
Table 2. Air Quality Readings for Eastern Toronto (August 20, 2009). Air Quality for TORONTO EAST Date Time AQI Cause 20-Aug-09 12:00 AM 32 Ozone (O3) 20-Aug-09 1:00 AM 31 Ozone (O3) 20-Aug-09 2:00 AM 29 Ozone (O3) 20-Aug-09 3:00 AM 27 Ozone (O3) 20-Aug-09 4:00 AM 22 Ozone (O3) 20-Aug-09 5:00 AM 20 Ozone (O3) 20-Aug-09 6:00 AM 17 Ozone (O3) 20-Aug-09 7:00 AM 17 Ozone (O3) 20-Aug-09 8:00 AM 15 Ozone (O3) 20-Aug-09 9:00 AM 18 Fine Particulate Matter (PM2.5) 20-Aug-09 10:00 AM 22 Fine Particulate Matter (PM2.5) 20-Aug-09 11:00 AM 21 Fine Particulate Matter (PM2.5) 20-Aug-09 12:00 PM 24 Ozone (O3) Source: MOE, 2009
At a local scale, no significant sources of air pollution exist within the immediate and surrounding study area. No component of this project is anticipated to degrade air quality or be influenced by local or regional sources of air pollution. Any impacts from machinery and/or vehicles used as part of the construction phase will be temporary and minimal, and are therefore not deemed to be significant.
Agriculture Tile or Surface Drains There is a storm sewer outfall located north-east of the project site as shown in Figure 9. The outfall is located within the Bellamy Ravine, south of Kingston Road. Run-off from the surrounding area flows through this outfall down the ravine and directly into Lake Ontario. A second storm sewer outfall is located further down the ravine, on the west side, which discharges stormwater originating from the Meadowcliffe Drive area.
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Figure 9. Location of Storm Sewer Outfall within Bellamy Ravine. Source: TRCA, 2006.
As previously noted the City of Toronto commissioned Winter Burnside to carry out a storm drainage study for the Meadowcliffe Drive area. The final Winter Burnside report in 2002 resulted in several upgrades being carried out by the City of Toronto in 2004. It is understood that these improvements included depression storage, enhanced ditches and storm sewers, and a landscaping component.
Noise Levels and Vibrations There are no noteworthy sources of noise or vibration located within this section of shoreline. There may be occasional maintenance work along Meadowcliffe Drive or Lakehill Crescent. Insignificant noise sources may consist of landscaping machinery along the bluffs, and powerboats traveling offshore.
Water Flow Regime (High / Base and Low / Base) Water levels in Lake Ontario have been regulated since 1960, however, regardless of controls, the lake levels fluctuate on a short term, seasonal and long-term basis. Seasonally, changes of about 0.5 m are expected. As depicted in the following graph, water levels generally peak in June and are at their lowest in December. The sample locations for Lake Ontario are at Port Weller, Toronto, Cobourg, Kingston, Rochester and Oswego (DFO, 2009). Although water levels below chart datum are rare, the lowest monthly mean on record is approximately 73.8 m (IGLD, 1985). Presently used datum for Lake Ontario is the International Great Lakes Datum (IGLD), 1985. To convert IGLD 1985 datum to Geodetic Datum in the Toronto area, 0.13 metres must be added to the IGLD 1985 elevation. 22 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Figure 10 depicts recent variation of water levels on Lake Ontario, on a month-to-month and year–to-year basis.
Figure 10. Lake Ontario Water Levels for 2008-2009. Source: DFO, 2009.
Table 3. Lake Ontario Water Levels. June 2009 Lake Ontario Mean for month (preliminary data) 75.16 m Mean for month last year 75.19 m Mean for month, last ten years 75.07 m Statistics for Period of Record 1918-2008 Maximum monthly mean/year 75.76 m (1952) Mean for month 75.04 m Minimum monthly mean /year 74.19 m (1935) Probable mean for next month 75.08 m Source: DFO, 2009. NOTE: All water levels are expressed in meters using 1985 International Great Lake Water Datum (IGLD85).
A summary of the water level variations and wind set up in this part of Lake Ontario is presented in Table 4. The summary is based on a water level analysis completed by the Ontario Ministry of Natural Resources (MNR, 1989).
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Table 4. Water Level and Set Up Summary for Lake Ontario at Toronto. Return Period (years) 5 10 25 50 100 Instantaneous Water Level (metres, IGLD85) 75.40 75.49 75.60 75.67 75.74 Highest Annual Monthly Water Level (m IGLD) 75.2 75.3 75.4 75.5 75.6 Wind Set Up, Wind Surges (metres) 0.21 0.24 0.28 0.31 0.34 Source: MNR, 1989.
Existing Surface Drainage / Groundwater Seepage /Groundwater Recharge and Discharge Zones In 2001, after a period of active erosion, TRCA commissioned Terraprobe Limited to carry out a geotechnical review of slope stability and erosion along the Lake Ontario shoreline immediately below Meadowcliffe Drive. The final report concluded that the erosion was primarily the result of toe erosion by wave action and surface run-off flowing over the slope crest. The firm recommended the following storm drainage upgrades:
• A significant upgrade of the stormwater collection system along the Meadowcliffe Drive right-of-way; and • Connection of existing roof eavestroughs to the street storm sewer.
Terraprobe also recommended a more detailed stormwater management assessment of the area be completed to determine the quantities of surface runoff over the slope crest.
As a result of the recommendations of the geotechnical report, the City of Toronto commissioned Winter Burnside to carry out a storm drainage study for the Meadowcliffe Drive area. The final Winter Burnside report in 2002 resulted in several upgrades being carried out by the City of Toronto in 2004. It is understood that these improvements included depression storage, enhanced ditches and storm sewers, and a landscaping component.
In 2006, Terraprobe was retained to review historical geotechnical investigations and complete additional inspections on the Meadowcliffe area, the firm reported surface drainage from the tablelands to the north of the project site to be directed into the stormwater outfall and conveyance channel that discharges into Lake Ontario via Bellamy Ravine. The groundwater was documented to be seeping at several elevations along the Meadowcliffe sector of the bluffs. In particular, 3 to 4 metres (m) below the slope crest was reported to have saturated bare patches, especially at 10, 16, 20, 30 and 32 Meadowcliffe Drive. Similar saturated patches of the bare slope were observed at an approximate depth of 6 to 8 m and again at 12 to 15 m (Terraprobe, 2006).
Littoral Drift / Sediment Transport Littoral cells are sections of the shoreline, which are defined by sediment transport. Sediment input and outflow are limited to the boundaries of the littoral cell. Defining the boundaries of these cells is important as any actions taken on the shoreline within a littoral cell can have consequences on other shoreline features located within the cell. As shown in Figure 11 the project area is influenced by one (1) individual littoral cell.
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Figure 11. Littoral cell boundaries located on the Toronto waterfront. Source: TRCA, 2004. The project area is located within the nearshore sediment transport cells, which captures the Lake Ontario shoreline from East Point Park in the east to Ashbridge’s Bay Park in the west. Sediment transport characteristics at the site were investigated using numerical models. A bulk energy sediment transport model was used to assess the stable orientation of a range of cobble sizes for the design of artificial beaches. A detailed predictor sediment transport program was used to assess the sediment transport pathways associated with the alongshore transport of sand. This was done to provide information for the impact assessment of the various concepts considered.
The net littoral drift direction at this site is from east to west. Atria (1993) calculated a sediment budget for the shoreline from the R.C. Harris filtration plant to East Point. Modelling undertaken by Shoreplan Engineering in 2007 determined that less than 5,000m3/yr of sediment is transported to the site. The existing wave climate is capable of transporting the full sediment supply past the site in water depths of approximately 2.5 metres below datum, and deeper. East Point forms the eastern limit of the littoral cell containing the Meadowcliffe Drive site. Table 5 shows the sediment supply rates that can be expected with the current level of shoreline protection. It can be seen that of the approximately 25,000 m3/yr of sediment that is supplied through shoreline erosion, 20,000 m3 of it comes from the Meadowcliffe Drive sector.
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Table 5. Sediment Supply Rates. % Supply Rate (m3/year) 1 Supply Rate (m3/year) Shoreline Sector Protected (prior to protection) (with protection) East Point 0% 1,225 1,225
Grey Abbey 0% 910 910
Guildwood Parkway 75% 3,140 785
Guild Inn 100% 3,975 0
South Marine Drive 100% 4,095 0
Sylvan Ave 90% 9,800 980
Meadowcliffe 0% 20,010 20,010
Total 43,155 23,910 1 from Atria (1994)
On the basis of a sediment bypassing analysis, Baird (1994) concluded that Bluffers Park could be considered to be a complete littoral barrier. Baird found that approximately 20 to 25% of the incoming supply would bypass the eastern-most headland, but would likely either be deposited in the entrance channel or deflected offshore at the western end of the park.
Wave Climate - Other Coastal Processes Land and water meet along the coastline. The coast is shaped mainly by the action of the waves, which reach the shore. Waves are created by the winds, which blow across the surface of the water. Friction results in the transfer of energy from the wind to the waves. Wave size is dependant on three factors: the strength of the wind; the length of time that the wind blows; and the distance over, which the wind blows (the fetch).
The most common direction in which the waves move is determined by the prevailing winds (i.e. the direction from which the winds blow most often). In the north-eastern portion of Lake Ontario, the prevailing winds are from the south-west and less frequently from the east. This area of Lake Ontario also has the greatest fetch. The fetch is known as the length of water surface exposed to wind during wave generation. Because of this factor the shoreline at the Scarborough Bluffs is exposed to the greatest wave action of the entire TRCA waterfront leading to the creation of the cliffs. A wave will break when it reaches shallow water. Therefore, the shoreline profiles have a great effect on the way the waves act in a certain area.
Wave hindcasting was used by Shoreplan to estimate the wave climate at an offshore location where changes in water depths do not effect wave generation and propagation. The 1:100 year condition has a significant wave height of approximately 6.0 metres and a peak wave period of 11 seconds. This wave will come from the east. The 1:100 year south-westerly condition has a significant wave height of 4.5 metres with a peak wave period of 9 seconds.
Nearshore wave climates at the site were produced by transferring the 33 years of hourly hindcast wave data from deep water in to the site using a numerical wave transformation model. Wave transformation models are required to account for the effects the changing bathymetry has on the waves as they propagate into the site. Nearshore wave height and wave energy distributions along the Meadowcliffe Sector indicate that the magnitudes of the easterly
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and southerly peak wave heights are similar, however more than 70% of the nearshore wave energy comes from the easterly direction.
Waves erode or wear away the base of the bluffs within the project area (e.g. Cudia Park and Meadowcliffe Drive) and transport the eroded material westward along the coastline, a process called littoral drift. Eventually, the material is deposited on the beach at Bluffers Park or is moved offshore.
When cohesive shorelines recede due to wave-induced erosion, the vertical erosion noticeable within the nearshore area is referred to as downcutting. Downcutting rates can be reasonably estimated from surveyed profiles if a sufficient time exists between surveys. As part of the Sylvan Avenue shoreline management plan Reinders et al (1994) estimated downcutting rates for four profiles. Averaging their results they estimated that the current 2 metre contour would be lowered by 0.9 metres in 40 years, 1.4 metres in 75 years, and 1.8 metres in 110 years. Using profile data surveyed by TRCA in 2006, Shoreplan confirmed the rate of downcutting to be consistent with Reinders et al (1994).
Water Quality Water chemistry is a major environmental concern. Many parameters affect aquatic life, such as fish and benthic invertebrates, in both the water column and sediment. Influences on lake water quality include: inputs from water pollution control plants, backwash water from water filtration plants, discharge from storm sewer outfalls, groundwater seepage, spills, erosion and sedimentation, wet and dry atmospheric deposition, and urban run-off. The modification of natural stream flows by dams and weirs can also affect water quality (TRCA, 2004).
The chemical characteristics of Lake Ontario have changed since the turn of the century. These changes reflect the accelerated eutrophication taking place in the lake as a result of urbanization. The following table contains the results from sampling events during the 1970’s. The location of the sampling was approximately three kilometers to the east of Bluffer’s Park Marina between Cathedral Park and Cudia Park within our study area limits.
Secchi disk readings offer a measurement of water clarity. According to the Provincial Water Quality Guidelines (PWQOs), water should have a Secchi disk transparency of at least 1.2 m (MOE, 1994). The information in Table 6 shows the transparency Secchi disk value ranged between 1.33 m and 2.84 m. From this data it is safe to assume that this level of water clarity is sufficient to support aquatic life.
Table 6. Historical Water Quality Measurements. Nearshore 1975 1976 1977 1978 Secchi Disk Clarity (m) 1.77 1.33 1.44 1.72 Conductivity (umhos) 331 335 328 270 Total Phosphorus (mg/L) 0.05 0.04 0.05 0.05 Fecal Coliforms (#/100mL) 4 3 7 3 Offshore 1975 1976 1977 1978 Secchi Disk Clarity (m) na 2.44 2.84 2.53 Conductivity (umhos) na 331 321 278 Total Phosphorus (mg/L) na 0.03 0.02 0.03 Fecal Coliforms (#/100mL) na 2 6 4 Source: TRCA, 1979.
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The next measurement, conductivity is a measure of how well water can conduct an electrical current. Conductivity increases with increasing amount and mobility of ions. Conductivity is an indirect measure of the presence of dissolved solids such as chloride, nitrate, sulfate, phosphate, sodium, magnesium, calcium, and iron, and can be used as an indicator of water pollution. All results for conductivity are well within normal levels and should be of no concern (Environment Canada, 2009).
Phosphorus is one of the key elements necessary for growth of plants and animals. Rainfall can cause varying amounts of phosphates to wash from soils into nearby waterways. Phosphate will stimulate the growth of plankton and aquatic plants which provide food for fish. Initially this increased growth may cause an increase in the fish population and improve the overall water quality (Environment Canada, 2009). However, if an excess of phosphate enters the waterway; algae and aquatic plants will grow rapidly and use up large amounts of oxygen. This condition is known as eutrophication. The rapid growth of aquatic vegetation can cause the death and decay of vegetation and aquatic life because of the decrease in dissolved oxygen levels (Environment Canada, 2009). According to the PWQOs to avoid nuisance concentration of algae in lakes, average total phosphorus should not exceed 0.02 mg/L. The nearshore measurements for total phosphorus are slightly above the PWQOs for nuisance algae compared with the offshore measurements. This can be attributed to run-off from surrounding residential lawns and is still therefore considered normal.
The presence of fecal coliform bacteria in aquatic environments could indicate that the water has been contaminated with the fecal material of man or other animals. At the time this occurred, the source water may have been contaminated by pathogens or disease producing bacteria or viruses which can also exist in fecal material. Some waterborne pathogenic diseases include typhoid fever, viral and bacterial gastroenteritis and hepatitis A. The presence of fecal contamination is an indicator that a potential health risk exists for individuals exposed to this water. Fecal coliform bacteria may occur in ambient water as a result of the overflow of domestic sewage or nonpoint sources of human and animal waste (Environment Canada, 2009). According to PWQOs fecal coliform counts of fewer than 100 counts per 100 mL is acceptable for recreation water use (MOE, 1994). As noted in the table above all of the sampling stations are well below this guideline and are of no concern.
Soil / Fill Quality The shorelands are composed of sand and silty sand. These sandy substrates derive from the eroded material from the Scarborough Bluffs. Offshore bedrock occurs 12 to 19 m below lake level, consisting of limestone formations of the Ordivician Period. There are no known soil quality issues within this sector of the waterfront.
Sediment Quality (Contaminated Soils/Sediment/Seeps) There are several factors that determine sediment contamination concentrations, these include; proximity to urban and agricultural sources of contaminants, the characteristics of the water body receiving the inputs, rates of shoreline erosion, binding mechanisms of sediment, the amount of organic matter, and the percentage of fine sediment. Toxic substances within sediments from industrial, municipal and non-point sources are a threat to the survival of benthic organisms and other fauna that feed on them. Water quality can also be affected by large amounts of contamination (CCME, 1999).
Historic sediment sample results for the regional study area exist for various offshore locations, including south of Sylvan Avenue and south of the South Marine Drive revetment. Sediments were tested for PCB/Organochlorine levels, general chemistry analysis (organic content,
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nutrients, and metals). Results of the laboratory analysis were compared against provincial sediment quality guidelines. These guidelines provide reference points when evaluating potential adverse biological effects on the aquatic community (CCME, 1999). The Provincial Sediment Quality Guidelines were developed by the Ontario Ministry of the Environment to assist with the protection of aquatic biological resources (MOE, 1993).
Table 7. Sediment Quality Results. Oil & Sample TOC TP TKN Grease As Ni Cd Cr Pb Hg Zn LOI 1990 Samples 1 0.05 1250 70 104 1 NA 0.2 NA <1 <0.01 13 2.8 2 0.09 555 50 119 0.8 NA 0.4 NA <1 <0.01 15 0.5 3 0.19 290 110 420 1.6 NA <0.1 NA <1 <0.01 18 0.9 4 0.59 250 300 164 1.6 NA 0.2 NA 12 <0.01 33 1.4 1993 Samples 1 0.16 590 <50 NA <0.5 <5 <0.2 10 2.5 <0.1 10 NA 2 0.19 710 <50 NA 0.6 <5 <0.2 9 2.5 <0.1 10 NA 3 0.13 270 <50 NA 0.9 <5 <0.2 <5 3 <0.1 9 NA 4 1.1 380 140 NA 1.8 19 <0.2 29 6 <0.1 35 NA LEL 1 600 550 1500 6 16 0.6 26 31 0.2 120 SEL 10 2000 4800 33 75 10 110 250 2 820 Source: TRCA, 1994. Note: Unless otherwise noted, results are reported in milligrams per kilogram (ppm) except for loss on ignition and total organic carbon which are expressed as a percentage, and cation exchange capacity which is expressed in milli-equivalents per 100 grams (meq/100g).
Five (5) results exceeded the Lowest Effect Level (LEL), three (3) of which occurred in the sediments from (1993), for chromium, nickel, and total organic carbon. Chromium and nickel levels were not measured in 1990. Total phosphorus LEL was exceeded on two occasions; station 1 in 1990, and at station 2 in 1993. Copper was detected at the LEL at station 4 (1993 sample).
No organochlorine compounds or PCB’s were detected in either the 1990 or 1993 sediment samples. Four PAH compounds were detected in the 1993 samples, at levels at, or just above detection limits. Fluoranthene was detected at stations 3 and 4 (1993); Pyrene and Chrysene were detected at stations 1, 3, and 4; and Benzo(b)fluoranthene was detected at station 4 (1993) only. None of these detections exceeded the Lowest Effect Levels as designated by the Ministry of the Environment (MOE).
Existing Transportation Routes Major arterial roads that service the study area include Kingston Road, Eglinton Avenue East, Brimley Road and Markham Road. The Canadian railway line is also located north of Kingston Road, providing commuter service via GO Transit. There are public transit buses through the communities along the Scarborough Bluffs (e.g. Bus 86 Scarborough) with various routes and times (TTC, 2009).
Currently, there is no access road at the base of the Scarborough Bluffs in the project area; however, there is a maintenance access road along the shoreline to the east of the project area which is owned by TRCA. This service road is accessible via the Guild Inn and travels to the west, ending at the terminus of Sylvan Park.
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Constructed Crossings There are currently no constructed crossings within the study area.
3.2.2 Biological Environment
Wildlife Habitat The project area provides limited habitat for mammal, bird and reptile species as the bluff face is too steep. The open water zone may support migratory and resident waterbirds. Loons, grebes, cormorants, geese, dabbling and diving ducks, gulls and terns use the open water during migration. The open water habitat currently provides little forage such as fish, aquatic invertebrates and zebra mussels for migrating and over wintering waterfowl and coastal birds nesting outside of the project area.
Habitat Linkages or Corridors The forested sections of the bluffs to the east and west of the project area provides corridors of habitat which link to several nearby ravines, including Bellamy and Grey Abbey, as well as linking smaller habitats with larger habitats such as East Point Park and the Highland Creek valley. The Scarborough Bluffs corridor of habitat and resulting linkage of habitat allows species such as coyote, red fox, and white-tailed deer to thrive on the waterfront (TRCA, 2004).
Significant Vegetation Communities To the east of the study area the Bellamy Ravine shoreline sector has a bluff face that is vegetated with a mixture of herbaceous plants, shrubs, and deciduous trees. The deep stream gullies are vegetated with a mixture of birch, poplar, cherry, maple, oak, hawthorne and willow while the steep cliffs remain bare. The forested bluff found east of Bellamy Ravine known as Guild Woods supports a rare red ash and silver maple forest community.
Environmentally Sensitive / Significant Areas (Biological) There are no designated biological Environmental Sensitive Areas located within the local study area; however ESA#124 known as Guild Woods is located to the east of the Meadowcliffe shoreline sector. This ESA is considered significant due to the presence of a red ash/silver maple forest community which is relatively scarce on the Toronto waterfront. The ESA is described as a flat tableland vegetated by mature forest cover comprised of white and red ash, sugar maple, and American beech. The soils are are generally wet with pockets of eastern hemlock, and white birch.
Fish Habitat Historically, the open coast areas of the Scarborough waterfront supported breeding coldwater fisheries which included lake trout, lake whitefish, round whitefish, and lake herring. The over- wintering eggs and larvae of these coldwater species require cobble reefs, and rocky shorelines that are kept clean of sediments by way of current and wave action (TRCA, 2006).
There are several limiting factors that affect fish production along Lake Ontario’s open coast habitat. These include intense wave action, size of substrates, shoreline erosion, localized water and sediment quality and water temperature fluctuations. Intense wave action during storm events and high winds impedes the development of aquatic plant communities therefore restricting feeding and cover areas for fish and other aquatic organisms (TRCA, 2004). As stated in the previous section the sand and silt substrates that dominate the open coast environment are unstable and subject to movement and transport along the waterfront due to regular lake activities. This movement of fine sediment fills in interstitial spaces and restricts spawning locations and oxygen availability to eggs that may have already been laid. Also the 30 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
fine sediment offers very little cover and variability on the bottom providing little cover for fish. The fish community of the eastern Toronto waterfront has been routinely monitored since 1989, specifically Bellamy Ravine East Beach, Scarborough Shoreline Meadowcliffe, Bluffers Park outer breakwall, and Bellamy Road. Results from seine and gill net locations from 1979 to 1986 are also available for areas such as Bluffers Park, Bellamy Ravine, and East Point waterfront area. A species list of fish collected in these areas for all years sampled is reflected in the following tables.
Based on their temperature requirements, fish species can be grouped into three broad fish communities as follows: cold water, cool water and warm water. But it should be noted that there is a certain amount of overlap among these broad community types. For example, during the summer when waters are at their warmest in Ontario, it is not uncommon to find some cold water species living in the same areas as cool water species, or cool water species living in the same areas with warm water species (Eakins, 2007).
Table 8. Fish Species Collected on the Scarborough Shoreline. Thermal Preference Food Habits Species List Scientific Name Non- Warm Cool Cold Piscivore Piscivore Alosa ● ● Alewife pseudoharengus American Eel Anguilla rostrata ● ● Blacknose Dace Rhinichthys obtusus ● ● Bluntnose Pimephales notatus ● ● minnow ● Bowfin Amia calva ● Brown bullhead Ameirus nebulosus ● ● Brown trout Salmo trutta ● ● Oncorhynchus Chinook salmon ● ● tshawytscha Coho salmon Oncorhynchus kisutch ● ● Common carp Cyprinus carpio ● ● Common shiner Luxilus cornutus ● ● Emerald shiner Notropis atherinoides ● ● Fathead minnow Pimephales promelas ● ● Dorosoma Gizzard shad ● ● cepedianum Lake chub Couesius plumbeus ● Lake trout Salvelinus namaycush ● ● Corregonus Lake whitefish ● ● clupeaformis Logperch Percina caprodes ● ● Longnose dace Rhinichthys catatactae ● ● Catostomus Longnose sucker ● ● catostomus Mottled sculpin Cottus bairdi ● ● 31 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Thermal Preference Food Habits Species List Scientific Name Non- Warm Cool Cold Piscivore Piscivore Northern pike Esox lucius ● ● Pumpkinseed Lepomis gibbosus ● ● Rainbow smelt Osmerus mordax ● ● Rainbow trout Oncorhynchus mykiss ● ● Rock Bass Ambloplites rupestris ● ● Prosopium Round whitefish ● ● cylindraceum Sand shiner Notropis stramineus ● ● Sea lamprey Petromyzon marinus ● ● Slimy sculpin Cottus cognatus ● ● Smallmouth Bass Micropterus dolomieui ● ● Spottail shiner Notropis hudsonius ● ● Tessellated darter Etheostoma olmstedi ● ● Threespine Gasterosteus ● ● stickleback aculeatus Percopsis Trout-perch ● ● omiscomaycus Walleye Sander vitreus ● ● White bass Morone chrysops ● ● White perch Morone Americana ● ● Catostomus White sucker ● ● commersoni Yellow perch Perca flavescens ● ● Source: TRCA, 2009 and Eakins, R. J. 2007. Ontario Freshwater Fishes Life History Database. Version 2.98. On-line database. (www.fishdb.ca), accessed 9 September 2009.
Table 9. Additional Fish Species Collected on the Scarborough Shoreline
Species List Scientific Name Preferred Habitat Shoals Shoals Shoals Alewife Alosa pseudoharengus ● American Eel Anguilla rostrata ● Blacknose Dace Rhinichthys obtusus ● Bluntnose minnow Pimephales notatus ● ● Bowfin Amia calva ● Brown bullhead Ameirus nebulosus ● Brown trout Salmo trutta ● ● Chinook salmon Oncorhynchus tshawytscha ● ● ● Coho salmon Oncorhynchus kisutch ● ● ● Common carp Cyprinus carpio ● Common shiner Luxilus cornutus ● ● Emerald shiner Notropis atherinoides ● 32 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Species List Scientific Name Preferred Habitat Shoals Shoals Shoals Fathead minnow Pimephales promelas ● Gizzard shad Dorosoma cepedianum ● ● ● Lake chub Couesius plumbeus ● ● Lake trout Salvelinus namaycush ● ● ● Lake whitefish Corregonus clupeaformis ● ● Logperch Percina caprodes ● Longnose dace Rhinichthys catatactae ● Longnose sucker Catostomus catostomus ● ● Mottled sculpin Cottus bairdi ● Northern pike Esox lucius ● Pumpkinseed Lepomis gibbosus ● Rainbow smelt Osmerus mordax ● ● Rainbow trout Oncorhynchus mykiss ● ● Rock Bass Ambloplites rupestris ● Round whitefish Prosopium cylindraceum ● ● Sand shiner Notropis stramineus ● Sea lamprey Petromyzon marinus ● ● Slimy sculpin Cottus cognatus ● ● Smallmouth bass Micropterus dolomieui ● ● ● Spottail shiner Notropis hudsonius ● ● Tessellated darter Etheostoma olmstedi ● ● Threespine stickleback Gasterosteus aculeatus ● ● Trout-perch Percopsis omiscomaycus ● ● Walleye Sander vitreus ● ● White bass Morone chrysops ● ● White perch Morone Americana ● White sucker Catostomus commersoni ● Yellow perch Perca flavescens ● ● Source: TRCA 2009 and Eakins, R. J. 2007. Ontario Freshwater Fishes Life History Database. Version 2.98. On-line database. (www.fishdb.ca), accessed 9 September 2009.
The fish community found at the site can be described as sparse but quite diverse. This can be attributed to the relatively cold water and high wind and wave action found along the shores of the Scarborough waterfront leading to a group a fish that is well adapted to these conditions. Hypolimnetic upwellings are common throughout the area which results in cold water being moved inshore by wind. These coldwater upwellings create intolerable conditions for most warm water species. Therefore warm water species are typically found along the open coast of the Scarborough waterfront during the summer months only.
Adversely, coldwater and game fish such as the salmonids are only found in the nearshore areas of the shoreline during hypolimnetic upwelling events and are not considered permanent residents of the area (TRCA, 2006). These fish along with the other piscivores use this nearshore area usually only during times of migration.
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Using the fisheries data available for the Scarborough shoreline, each fish species preferred habitat type, thermal and food guild is categorized in Table 7. The representation of the data in this form can be used to classify the site as a cool to cold water fishery. Coolwater species represent 52.5% of the total inventory. Cold water species represent 25% of the total inventory and have highest percentage of piscivores at 12.5%. These findings are consistent with the findings for the EA performed on the Guild Inn Sector of the Scarborough shoreline.
As stated above this section of shoreline is classified as a cool-cold water fishery but serves as a migration corridor for other species during the summer months. There are several sheltered embayments along this section of waterfront that provide significant warm water fish habitat which include Bluffers Park and the mouth of Highland Creek. During periods of hot dry weather with little to no wind or wave action, conditions in the nearshore areas of the project site can be warm enough to support warm water fisheries allowing for migration between warm water habitats. Therefore, this area of nearshore habitat acts as a corridor and is important to allow for colonization and replenishment of fish communities in other isolated warm water habitats.
Species of Concern A local significance “L-Rank” has been created by TRCA and it is applied to species, or communities to provide a measure of their biological significance, or abundance in a Greater Toronto Regional context. Local ranks “L-Ranks” are assigned according to a variety of biological criteria including provincial and national significance. L-Ranks represent a scale of significance that ranges from L1 to L5. L1 or a low L-score represents a high significance, and high L-score represents low significance. Also included is L+, which indicates a non-native species or community which is not ranked in the range.
Typical L-Rank Description: L1 Extremely significant in TRCA Region due to rarity, stringent habitat needs, and/or threat to habitat L2 Highly significant: occurs in high-quality natural areas and is probably declining in the Toronto area, often already rare L3 Locally significant: generally occurs in natural rather than cultural areas; may be vulnerable to decline L4 Generally secure; may be a conservation concern in a few specific situations L5 Dependent on degraded, often urban habitats; not a conservation concern L+ non-native species or community which generally requires management unless special conservation concern exists
Some of the criteria used in this database include: local occurrence, population trend, habitat dependence, area sensitivity, mobility restriction, and sensitivity to development. The following table represents the “L” rating for species of concern for the Cudia Park/Bellamy Ravine section of the Scarborough Shoreline. Several of the species in the table have an “L” rating of L2 indicating that this area contains species of concern and should be protected and maintained in order to enhance diversity.
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Table 10. Flora Species of Concern. Flora Species of Concern Cudia Park / Bellamy Ravine Scientific Name Common Name Level of Concern (L1-L4) Acer spicatum Mountain Maple L4 Actaea pachypoda White Baneberry L4 Allium tricoccum Wild Leek L3 Anemone acutiloba Sharplobed Liverleaf L3 Asarum canadensis Canadian Wild Ginger L4 Aster umbellatus Flat-topped White Aster L4 Betula allegheniensis Yellow Birch L3 Carya cordiformis Bitternut hickory L4 Caulophyllum thalictroides Blue Cohosh L2 Corylus cornuta Beaked Hazel L3 Cornus rugosa Round-leaved dogwood L3 Desmodium glutinosum Pointed-leaved tick-trefoil L3 Dryopteris marginalis Marginal woodfern L4 Elymus canadensis Canada wild rye L3 Elymus hystrix Eastern bottlebrush grass L4 Helianthus decapetalus Thin-leaved sunflower L3 Helianthus strumosus Paleleaf woodland sunflower L4 Impatiens pallida Pale touch-me-not L4 Juglans cinerea butternut L3 Juncus torreyi Torrey’s Rush L4 Polystichum aerostichoides Christmas fern L3 Quercus alba White oak L2 Rosa blanda Early wild rose L4 Shepherdia Canadensis Ruset buffaloberry L2 Solidago arguta Atlantic goldenrod L4 Viburnum acerifolium Mapleleaf viburnum L3 Source: TRCA, 2009.
The Monarch butterfly (Danaus plexippus) which inhabits the study area is designated as a Species of Special Concern. The forest found at the Guild Inn to the east supports provincially rare wood reedgrass (Cinna arundinacae).
Exotic/Alien and Invasive Species An aquatic invader is a non-native species, whose introduction will likely cause (or has already caused) damage to the host ecosystem, existing species therein, the economy or human well- being. Invasive species thrive in the absence of their native predators and have the potential to drastically alter habitat, rendering it inhospitable for native species. Aquatic invasive species (AIS) have already been responsible for significant devastation of some native fish species and fisheries in Canada (DFO, 2009).
Within the aquatic community there are eight (8) alien fish species. Fish such as rainbow trout, Chinook salmon, and brown trout have been introduced to improve recreational sport fishing opportunities in Lake Ontario. Other species such as common carp and goldfish have also been intentionally introduced, however are not considered a popular sport fish. White perch are of concern as it can compete for habitat with walleye and potentially reduce its populations. It also will interbreed with the native white bass (TRCA, 2004).
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Another species of growing concern is the round goby. It has been captured in very low numbers around the site in question however this fish is typically hard to capture with both the electrofishing vessel and the seine net. Round Gobies have spread rapidly within the Great Lakes since their discovery in 1990. They are very competitive and populate quite easily. In addition to habitat domination, they will also eat the eggs and the young of indigenous fish. It is presumed that they arrived via the ballast water of transoceanic vessels (DFO, 2009).
Terrestrial exotic species can cause problems similar to those threats within the aquatic community. They also have the ability to out-compete native species and pose significant risk for the continued existence of the species itself. Some of the exotic species include tree of heaven, purple loosestrife, garlic mustard, and Norway maple. These species reproduce prolifically and as mentioned above tend to out-compete many desirable plant species (GLIN, 2009).
Wildlife/Bird Migration Patterns This area of shoreline along the Lake Ontario waterfront serves as a major migratory corridor for wildlife and birds. This project site is located within an important migratory zone which encompasses both the Atlantic and Mississippi flyways.
Songbirds rely on the vegetated slope of the Scarborough Bluffs when in need of rest, food, or shelter from adverse weather conditions during migration. This habitat near the shoreline serves as an important staging area for these birds when they are most vulnerable. The following table represents a summary of the Toronto Ornithological Club database for bird species observed between January 1, 1930 and August 18, 2002 at Bluffer’s Park, Cudia Park, Sylvan Park, Guildwood Park, and Scarborough Bluffs.
Table 11. Bird Species Observed on the Scarborough Shoreline.
Species List Scientific Name Preferred Habitat Shoals Shoals Shoals Alewife Alosa pseudoharengus ● American Eel Anguilla rostrata ● Blacknose Dace Rhinichthys obtusus ● Bluntnose minnow Pimephales notatus ● ● Bowfin Amia calva ● Brown bullhead Ameirus nebulosus ● Brown trout Salmo trutta ● ● Chinook salmon Oncorhynchus tshawytscha ● ● ● Coho salmon Oncorhynchus kisutch ● ● ● Common carp Cyprinus carpio ● Common shiner Luxilus cornutus ● ● Emerald shiner Notropis atherinoides ● Fathead minnow Pimephales promelas ● Gizzard shad Dorosoma cepedianum ● ● ● Lake chub Couesius plumbeus ● ● Lake trout Salvelinus namaycush ● ● ● Lake whitefish Corregonus clupeaformis ● ● Logperch Percina caprodes ● Longnose dace Rhinichthys catatactae ● 36 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Species List Scientific Name Preferred Habitat Shoals Shoals Shoals Longnose sucker Catostomus catostomus ● ● Mottled sculpin Cottus bairdi ● Northern pike Esox lucius ● Pumpkinseed Lepomis gibbosus ● Rainbow smelt Osmerus mordax ● ● Rainbow trout Oncorhynchus mykiss ● ● Rock Bass Ambloplites rupestris ● Round whitefish Prosopium cylindraceum ● ● Sand shiner Notropis stramineus ● Sea lamprey Petromyzon marinus ● ● Slimy sculpin Cottus cognatus ● ● Smallmouth bass Micropterus dolomieui ● ● ● Spottail shiner Notropis hudsonius ● ● Tessellated darter Etheostoma olmstedi ● ● Threespine stickleback Gasterosteus aculeatus ● ● Trout-perch Percopsis omiscomaycus ● ● Walleye Sander vitreus ● ● White bass Morone chrysops ● ● White perch Morone Americana ● White sucker Catostomus commersoni ● Yellow perch Perca flavescens ● ● Source: Toronto Ornithological Club, 2002.
Wildlife Population Reports conducted by TRCA (2000) indicate that this section of shoreline is very disturbed, with significant fragmentation of natural areas. Overall, these areas attract a good assortment of common garden and city birds, though sightings of unusual species have been observed. Observed wildlife species within the immediate study area and adjacent woodlots are indicative of well-established suburban residential areas usually associated with older more developed areas.
Resident wildlife within the study area include Eastern red fox (Vulpes vulpes), eastern cottontail (Sylvilagus floridanus), grey squirrel (Sciurus carolonensis), striped skunk (Mephitis mephitis), raccoon (Procyon lotor), coyote (Cabis latran), little brown bat (Myotis lucifugus), meadow vole (Microtus pennsylvanicus), white-footed mouse (Permyscus leucopus), muskrat (Ondatra zibethicus), beaver (Castor canadensis), white-tailed deer (Odocoileus virginianus), Eastern chipmunk (Tamais striatus), woodchuck (Marmota monax), and Virginia opossum (Didelphis virginiana). The local wildlife populations are supported by the continuous corridor of habitat provided by the Scarborough Bluffs (TRCA, 2004).
Wetlands In 2008, TRCA constructed a wetland adjacent to the East Beach at Bluffers Park to capture overland runoff and ground water seepage from the Scarborough Bluffs. The wetland project included restoration of native wetland plant communities, creation of boardwalks, and installation of post-and-rope fencing to direct public access through sensitive plant 37 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
communities. These works were completed as part of a recent initiative of the Mayor David Miller to improve recreational beaches.
Microclimate Meteorological conditions — wind, nearshore wave climate, regional climatic conditions, solar heating, and thermal characteristics — have considerable influence on shoreline conditions and aquatic habitats. Winds, in combination with over-water fetch lengths, determine wave conditions across the Toronto waterfront. A high percentage of lake currents and most nearshore waves are induced by wind conditions. Winds are responsible for the lake-wide circulation patterns that create the west-to-east ambient currents throughout the Toronto waterfront. Although prevailing winds are generally from the west, the much longer eastern fetches produce far more wave energy coming from the east. In the eastern sector of the Toronto waterfront the predominant eastern wave energy is partially balanced by wave energy from the southwest.
Daily and seasonal weather conditions, especially solar heating, play a critical role in the ecology of Lake Ontario. The lake waters stratify according to temperature in the summer and winter. The amount and intensity of solar heating defines the scope and extent of this thermal stratification and the subsequent aquatic habitat conditions. Two additional temperature- induced conditions that dramatically affect nearshore habitats are the formation of a thermal bar and hypolimnetic upwellings.
Early in the spring the nearshore waters of the lake heat up and form a band of warm water that is held in place by a thermal bar consisting of colder, denser off-shore water. The warmer water builds in depth and concentrates warm water discharges from rivers, creeks and storm drains within the nearshore area. This phenomenon typically lasts until mid June, and surcharges the nearshore area with warm, nutrient-rich water. The early season influx of nutrients has a profound effect on aquatic life by promoting primary production and accelerating the establishment of warm, eutrophic conditions along the shoreline of the oligotrophic Lake Ontario. The thermal bar dissipates into full stratification in the early summer and under the appropriate wind conditions is vulnerable to hypolimnetic upwellings of deep cold lake water.
Unique Habitats As previously stated, the Scarborough Bluffs are utilized as songbird migratory corridor, located within the migratory zone which encompasses both the Atlantic and Mississippi flyways. In aquatic habitats, the combination of cold water and extensive wave action primarily creates a coldwater fishery, however, sheltered embayments east of Bluffers Park and the mouth of Highland Creek provide habitat for warm water species.
Areas of Natural Scientific Interest - Life Science (ANSI-LS) The entire Scraborough Bluffs is considered an Area of Natural Scientific Interest for Life Science (see Figure 7), as the bluffs possess the following notable life science features:
“The deep stream gullies are vegetated with a mixture of birch, popular, cherry, ample, oak, hawthorne and willow while the steep cliffs are bare. Some sections of the tableland rim contain maple-oak-ash. Numerous metropolitan parks and residential development abut the cliff rim” (OMNR, 1984).
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As the project area is along the shoreline of the Scarborough Bluffs, TRCA recognizes that the life science features of the bluffs are significant. Any works conducted along this sector will be conducted to minimize and mitigate potential negative impacts.
3.2.3 Cultural Environment
Traditional Land Uses Archaeological evidence gathered in this area shows that the First Nations people established settlements along the Scarborough Bluffs dating back 10,000 years, making this one of the oldest inhabited sites in Toronto. Refer to Archaeological Resources, Built Heritage Resources and Cultural Heritage Landscapes for more details.
Furthermore, Doris McCarthy, a renowned Canadian artist, bought her property at 1 Meadowcliffe Drive in 1939 and still resides on this property today. In 1986, Doris McCarthy was interested in conserving a portion of her property located on the bluffs and donated seven (7) acres of her land to TRCA under the Erosion Control Agreement. In 1998, another portion of her property was donated to the Ontario Heritage Trust, which is known as “Fool’s Paradise” and is used for heritage and artistic activities. Fool’s Paradise is seen to have a rare combination of natural, archaeological and cultural heritage.
Aboriginal Reserve or Community There are no reserves or known communities within the study area.
Outstanding Native Land Claim There are no known native land claims within the study area.
Riparian Uses The study area is located within the “Cliffcrest” neighbourhood in the former City of Scarborough. The property located within the study is mainly owned by private landowners, more specifically there are 16 residential properties that back directly onto the bluffs. TRCA owns some waterfront property towards the east end of the project area. The area below Cudia Park is owned by TRCA and maintained by the City of Toronto. However, there will need to be an agreement between the private landowners and TRCA prior to the commencement of the shoreline remedial works.
Recreational or Tourist Use of Water Body and/or Adjacent Lands The study area is located just east of Bluffers Park. This lakeside park features a double launching ramp, visitors dockage, and yacht clubs. Part of the park provides secure berths for over 500 boats operated by the Bluffers Park Boating Federation.
Recreational or Tourist Use of Existing Shoreline Access Locations Bluffers Park has a day use park which includes a sandy beach, picnic areas, walks, lookouts, and a restaurant.
As of the summer 2009, Bellamy Ravine has a formal gravel pedestrian pathway from the top of Bellamy Ravine to the shoreline of Lake Ontario. Additionally there is a maintenance access road located below Sylvan and South Marine Drives, located to the east of the project area, which is accessed via the Guild Inn. This informal service road owned by TRCA provides pedestrian access to the waterfront.
Aesthetic or Scenic Landscapes or Views 39 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
The Scarborough Bluffs stretch for about 14 km along the Lake Ontario shore, from the Eastern Beaches of Toronto in the west and to West Hill in the east. The bluffs rise 65 m above the water at their highest at Cliffside. The Scarborough Bluffs are considered a natural wonder that was formed following the last ice age about twelve thousand years ago. The bluffs have been formed primarily by erosion of the packed clay soil.
Archaeological Resources, Built Heritage Resources and Cultural Heritage Landscapes The following information was provided by TRCA Archaeological Resources.
Palaeo-Indian Period - ca. 11,500 to 9,000 BP Twelve thousand years ago as the glaciers retreated from southern Ontario, nomadic peoples gradually moved into the areas recently vacated by the massive ice-sheets. As the glaciers melted, much of the landscape of southern Ontario came to resemble spruce-tundra regions of the present day eastern sub-arctic. During this time period, the water levels and shorelines of lakes Huron and Ontario fluctuated considerably due to large quantities of glacial meltwater. Traditionally, archaeologists’ knowledge of the Palaeo-Indian occupations of southern Ontario was limited primarily to sites associated with these glacial lake shorelines. However, recent investigations of archaeological sites located in the vicinity of Toronto indicate that these peoples also exploited interior locations away from glacial lake shorelines. It is thought that these Palaeo-Indians lived in small family groups and hunted caribou and other fauna associated with the cooler environment of that time. Archaeologists’ understanding and reconstruction of this early period of Ontario’s past remains incomplete. Much of this reconstruction is substantiated from a small number of sites, limited artifact collections, and rare archaeological finds such as the discovery of arctic hare, fox, and possibly caribou bone fragments at the Udora site (a Palaeo-Indian encampment) near the south shore of Lake Simcoe.
At present, there is no evidence of Palaeo-Indian occupations along the shoreline of the project area. This is likely due to the fact that water levels in Lake Ontario were slightly lower during Palaeo-Indian times than they are now. Once the glacial meltwaters had drained out of the Great Lakes, circa 11,400 years ago, Lake Ontario was approximately 80 metres below the present water level. Evidence of Aboriginal occupations dating from that time until circa 4,000 years ago have likely been destroyed by rising waters or, much more recently, by the dredging of the lake bottom by the ‘stone hookers’ in the mid-1800s. It is possible that many of these early sites may be preserved underwater, and that these sites may be able to teach people of the future about this era in Ontario’s history. Several Palaeo-Indian sites are known from areas within the Humber River watershed suggesting that similar discoveries along the tablelands of the Scarborough Bluffs may be discovered.
Archaic Period - ca. 9,000 to 3,000 BP As the climate in southern Ontario warmed, the environments and fauna changed. As a result, many new technologies and subsistence strategies were introduced and developed by the Aboriginal peoples. Wood working implements such as groundstone axes, adzes and gouges begin to appear, as do net-sinkers (for fishing), numerous types of spear points and items made from Native copper, which was mined from the Lake Superior region. The presence of Native copper on archaeological sites in southern Ontario and adjacent areas suggests that Archaic groups were already involved in long range trade and interaction with one another. The trade networks established at this time were to persist between Native groups until European contact.
To harvest the new riches of the warming climate, Archaic bands of southern Ontario followed
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an annual cycle which exploited seasonably available resources in differing geographic locales within watersheds and along lakeshores. For example, from spring through fall, bands would have joined together and inhabited sites in lakeshore environments where abundant foodstuffs such as fish, waterfowl and wild rice enabled the establishment of larger multi-season occupations. Due to the extreme difficulty of scaling the bluffs to reach the water’s edge and the relatively low fisheries productivity associated with an exposed open coast environment, it is unlikely that aboriginal communities would have used the Guildwood Parkway shoreline for collecting aquatic foodstuffs and resources. As the seasons changed and aquatic resources became scarce, these bands split into smaller groups and moved inland to exploit other resources which were available during the fall and winter such as deer, rabbit, squirrel and bear which thrived on the forested margins of these areas.
Very little is known about the specifics of life for the people of the Archaic period. This is due in part to the lack of detailed excavation of these sites, and part to the changes in water levels discussed above. As well, archaeological sites representative of these early nomadic activities are small and therefore often deemed insignificant. It is likely that many of these sites were destroyed as development changed the face of the waterfront.
Initial Woodland Period - ca. 3,000 to 1,300 BP (AD 700) Early in the Initial Woodland period (3,000 - 2,000 BP), band size and subsistence activities were generally consistent with the groups of the preceding Archaic. Associated with the earliest components of this cultural period is the introduction of clay pots. Ceramic vessels provide a means for longer term storage of foodstuffs. With the ability to store foodstuffs during times of plenty, the stress of harder times was greatly reduced as it would have been possible to take advantage of the accumulated goods. Additionally, around 2,000 BP a revolutionary new technology, the bow and arrow, was brought into southern Ontario and radically changed the approach to hunting. These two technological innovations allowed for major changes in subsistence-settlement patterns. As populations became larger, camps and villages with more permanent structures were occupied longer and more consistently. Generally, these larger sites are associated with the gathering of two or more band groups into what are referred to as 'macrobands.' Often these larger groups would reside in favourable locations to cooperatively take advantage of readily exploitable resources such as fish.
It was also during this period that more elaborate burial rituals such as cremation, burial mound construction (as seen at the Serpent Mounds near Peterborough, Ontario, for example) and the interment of numerous exotic grave goods with the deceased began to take place. In fact, these goods, which include large caches of well-crafted lithic blades, sheets of mica, marine shells, shark teeth, silver and copper beads, and artifacts such as platform smoking pipes and decorative ear ornaments, all indicate that the Initial Woodland period was one of increased trade and interaction between southern Ontario populations and groups from as far as the east coast and the Ohio Valley.
Ontario Iroquoians (Late Woodland Period) - 1,300 to 450 BP (AD 700 to 1651) Around AD 700 corn was introduced into southern Ontario from the south. With the development of horticulture as the predominant subsistence base, the Late Woodland period gave rise to a tremendous population increase and the establishment of permanent villages (which were occupied from 5 to 30 years). These villages consisted of numerous cigar-shaped structures, or "longhouses," made from wooden posts placed in the ground and tied together at the top in an arch-like fashion. Although these windowless structures were only 6 metres (20 feet) wide (and the same in height), they extended anywhere from 9 to 45 metres (30 to 150 feet) in length providing shelter for up to 50 people. Quite often these villages, some of which
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were 3 to 10 acres in size, were surrounded by multiple rows of palisades suggesting that defence was a community concern during this period.
After centuries of small scale warfare and the gradual depletion of such resources as soil nutrients and firewood, the Late Woodland groups that inhabited the Scarborough Area and adjacent watersheds began moving their villages northward towards Georgian Bay. It was these groups that eventually evolved into the Petun and Huron Nations witnessed and recorded by the early French missionaries and explorers during the seventeenth century. Ultimately, both of these groups were exterminated through contact with Europeans, the spread of disease epidemics, and continued warfare with the Iroquois from New York State.
Contact Period - AD 1650 to 1800 During the late 1500s and early 1600s, European explorers sailed along the north shore of Lake Ontario and likely camped in the areas later to become Toronto and Eastern Scarborough. They were not looking for a nice place to live, but were seeking a route that would take them to the Orient. Etiénne Brûlé, sent to Pennsylvania by Samuel de Champlain in 1615, was likely one of the first to see the stark and majestic Scarborough Bluffs. For at least two centuries prior to British settlement, the Scarborough Bluffs and adjacent tableland must have remained a harsh and unpopulated area. While the Maritimes and Quebec were experiencing great changes brought by French and British exploration and settlement, the Scarborough Bluffs likely saw humans only occasionally, either when Native groups travelled through for food or trade, or when the occasional European fur trading or exploring expeditions stopped to gaze at the spectacular view from the top of the bluffs. The majestic cliffs would have dominated the landscape from the water. However, it was the forest on top of the bluffs that would have made an outstanding place for humans to rest and gather supplies but, at the time, was not a favoured location for year-round living due to the inaccessibility to the shoreline and the lack of well defined surface water sources.
Following the dispersal of the Petun and Huron by the Iroquois in 1650, southern Ontario lay vacant for fifteen years. Then, during the mid 1660s in an attempt to expand their fur hunting grounds to the north, the Iroquois - or more specifically the Seneca - established a number of villages along the north shore of Lake Ontario. These villages were large and at least two were located in the Humber and Rouge River watersheds.
The early 1700s saw the arrival of the Mississauga from the north. Concentrated in what has is now Etobicoke and Mississauga, these semi-nomadic Algonkian speakers most probably gathered plant foods, hunted and fished in the watersheds to the west and along the lakeshore. Following the American Revolution, displaced United Empire Loyalists sought land in Upper Canada. The need for suitable land led to the Toronto Purchase in September of 1787, encompassing an area from the mouth of Etobicoke Creek to Woodbine Avenue and almost as far north as Newmarket. In 1805, this agreement was made official. By the mid 1790s, most of the Mississauga groups had moved west to the Credit River and later to the Grand River, so that only occasional hunting and trading parties were seen passing through the Toronto area. Lands east of Woodbine Avenue were purchased as needed to connect Niagara with present- day Kingston. A road through Scarborough was built by settlers in 1801, which encouraged further settlement in the area.
At present, TRCA database has record of registered archaeological sites (from the Ministry of Culture) and indicates that there are four known sites within several kilometers of the study 42 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
area. One site is located near TRCA’s Guildwood shoreline project (Ministry Id# is AKGt-032). This site is of an undetermined time period and cultural affinity. The three other sites include the 'Midland' site (AkGt-007) a burial of undetermined age/culture, the 'McCowan' site (AkGt- 037) a multi-component (two or more occupations) probable campsite, and the 'Heinze' site (AkGt-015) a campsite of undetermined age.
Historic Canals There are no historic canals located within the project limits.
Federal Property There is no federal property affected by or located within the project site.
Heritage River Systems There are no heritage river systems located within the project site.
3.2.4 Socioeconomic Environment
Surrounding Neighbourhood or Community The neighbourhood surrounding the project area is characterized by low-density residential properties. In the 1960’s, the city planners of Scarborough named the community Cliffcrest in reference to the Scabrough Bluffs, which skirts the southern boundary of this neighbourhood. A map illustrating the boundaries of the Cliffcrest community is shown in Figure 12.
Figure 12. Boundaries of Cliffcrest Community. Source: City of Toronto, 2006. The property located at 1 Meadowcliffe Drive is the home of Doris McCarthy, a renowned Canadian artist. In 1986, Doris McCarthy was interested in conserving a portion of her property
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located on the bluffs and donated seven (7) acres of her land to TRCA under the Erosion Control Agreement. In 1998, Ms. McCarthy’s property along the crest of the slope, known as “Fool’s Paradise” was donated to the Ontario Heritage Trust for heritage and artistic activities. Fool’s Paradise is seen to have a rare combination of natural, archaeological and cultural heritage.
The Cliffcrest community is located within Ward 36 of the City of Toronto. Cliffcrest is situated in east Toronto. It is bounded to the west by Midland Avenue, Bellamy Road and Ravine to the east, the Canadian National Railway (CNR) tracks to the north and Lake Ontario to the south. The Cliffcrest community is home to approximately 14, 530 people and consists of about 5, 575 households. The community is composed of 17.4 % children (0 – 14), 12.9 % youth (15 – 24 yrs), 53.4 % working age individuals (25 – 64 yrs), and 16.4 % seniors (65 years or greater) (City of Toronto, 2001). The average household income is $72,521, below that of the larger city, which averages $80,343 (City of Toronto, 2006).
Surrounding Land Uses or Growth Pressure The study area is located within a well-established residential neighbourhood, and as such is subject to limited growth pressure. Due to the age of the homes within the study area, there is evidence of several properties undergoing major renovations; however presently there is no new development.
Existing Infrastructure, Support Services, Facilities There is no existing infrastructure within the limits of the proposed work, however, within the study area there is typical residential infrastructure (e.g. electrical lines, storm and sanitary sewers, watermains) as well as park-related infrastructure (e.g. asphalt pathways, parking lots, and washrooms).
Pedestrian Traffic Routes Bluffers Park, located to the west of the project area and Bellamy Ravine to the east provides access to the waterfront for pedestrians. There is no waterfront beach or pedestrian access along the shoreline south of Meadowcliffe Drive and Lakehill Crescent.
Property Values or Ownership Within the study area there are twelve (12) properties along Meadowcliffe Drive and another four (4) properties along Lakehill Crescent. The properties located within the study area include private residential and a designated heritage site owned by Ontario Heritage Trust. Due to the location of these properties and their view of Lake Ontario, these properties on average have a market value estimated to be between $1.8 and $2 million.
Existing Tourism Operations There are no known tourism operations within the project area. Bluffers Park to the west of the local study area is a tourist area that offers a sandy beach, picnic areas, walks, lookouts, and a marina. While the historic Guild Inn property to the east has unique formal gardens, art and sculpture displays that attracts visitors and is a popular wedding photography site. Plans are underway to introduce a restaurant, hotel and conference centre.
Property/Farm Accessibility 44 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Currently Cliffcrest community memebers have restricted access to the project area from the top of the bluffs due to the height and angle of the bluff face. However, as previously noted, several Meadowcliffe and Lakehill property owners have riparian rights to the shoreline, as such an agreement must be in place with these property owners prior to any commencement of shoreline works.
3.2.5 Engineering/Technical
Rate of Erosion in Ecosystem In 2006, Terraprobe carried out detailed site investigations and slope stability assessments for the bluff fronting Meadowcliffe Drive. Terraprobe noted that the average bluff slope inclination was about 1.2 h: 1.0 v (horizontal: vertical). The typical bluff height was reported as 57 metres. The upper portion of the slope was characterized as predominantly bare with inclinations varying from 1 h: 1 v to 1.4 h: 1.0 v. Using aerial photographs Terraprobe estimated the average annual recession rate at the toe of the bluff from 1980 to 2005 to vary from 1.1 to 1.3 m per year. Terraprobe identified that a stable bluff profile can be achieved if the toe of the bluff is stabilized. An average value of 1.2 metres per year was adopted for this study.
Sediment Deposition Zones in Ecosystem The net littoral drift direction at this site is from east to west. Approximately 25,000 m3 /y of sediment that is supplied through shoreline erosion along the Scarborough Bluffs (R.C. Harris filtration plant to East Point), 20,000 m3 of which originates from the Meadowcliffe Drive sector. A study conducted by Baird (1994) concluded that Bluffers Park could be considered to be a complete littoral barrier. It was found that approximately 20 to 25% of the incoming supply would bypass the eastern-most headland, but would likely either be deposited in the entrance channel or deflected offshore at the western end of the park.
Flood Risk in Ecosystem Varying water levels along the shoreline play a factor in localized flooding in low-lying areas. Water levels are known to change on a daily, seasonal, and annual basis. Waterfront projects are managed and designed in response to these known changes.
Slope Stability As previously noted, Terraprobe (2006) estimated the average annual recession rate at the toe of the bluff from 1980 to 2005 to vary from 1.1 to 1.3 m year. An average value of 1.2 m per year was adopted for this study. Average bluff slope inclination was about 1.2:1.0 (horizontal:vertical). Once the toe is stabilized the lower section of the bluff will obtain a stable slope of 2.5: 1.0 (h: v) and the upper 30 metres will obtain a stable slope of 1.5: 1 (h: v).
Using stable slope calculations from earlier work Terraprobe determined a long-term stable slope crest (LTSSC) position based on the 2005 position of the toe. Terraprobe also recommended that any toe protection works be situated 30 m lakeward of the existing toe of the bluff. That 30 metre buffer provides a suitable measure of safety for construction activity along the toe and allows room for the bluff to self-stabilize without talus spilling over the access road or protection structure. Positioning the landward edge of the shoreline protection structure 30 metres offshore of the current shoreline will also affect the predicted LTSSC.
Existing Structures
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The tableland at Meadowcliffe Drive and Lakehill Crescent is privately owned with 16 residential properties backing onto the bluffs. In all it is estimated that 12 properties are affected by erosion and bluff instability. Terraprobe (2006) estimated that the LTSSC is predicted to be projected inland by about 48 m on average from the 2005 slope crest assuming that wave erosion at the slope toe had been mitigated. Terraprobe’s final report, concluded that at least 5 houses are between 0 and 10 m from the LTSSC and that several others are within 25 m of this projected slope crest. A heritage property and municipal roadway are also within the area of identified risk. Based on the significant recession of the slope toe and respective recession of the LTSSC, Terraprobe strongly recommended that shoreline works be implemented.
Hazardous Lands / Hazardous Sites Hazard lands within the Regional Study Area include all nearshore waterfront lands which are susceptible to flooding or which have unstable slopes or soils. TRCA administers Ontario Regulation 166/06: Development, Interference with Wetlands and Alteration to Shorelines and Watercourses. Through this regulation TRCA has the ability to prohibit, regulate or require permission for development where the control of erosion may be affected. TRCA has delineated a Regulation Limit which identifies TRCA’s area of interest based on hazards associated with the Lake Ontario shoreline including the 100 year flood level and predicted LTSSC of the bluffs. All residential properties located along the shoreline within the study area are within this Regulation Limit.
4.0 DESCRIPTION OF PRELIMINARY ALERNATIVE CONCEPTS
Eight (8) variations of four (4) preliminary concepts were developed to address the erosion problem at Meadowcliffe Drive. The variations included protecting either the entire study area or only the portion in front of Meadowcliffe Drive as well as using either land access or marine construction techniques. Each of these preliminary designs represents all reasonable and feasible alternative solutions to the problem, including a “Do-Nothing” alternative. These alternative options are outlined in Section 4.1 through Section 4.7. 4.1 Preliminary Alternative Concepts
4.1.1 “Do-Nothing” Alternative
The “Do-Nothing” option is a mandatory alternative that must be considered in the Class EA process, as it helps to justify the need to undertake a remedial flood or erosion control project. Should the “Do-Nothing” option or other Conservation Authority programs such as land acquisition be deemed to be a more acceptable solution, then there is no further consideration for remedial action and the Class EA process terminates.
Under the “Do-Nothing” alternative erosion will continue along the shoreline east of the beach retained by the Bluffers Park headland. As the shoreline erodes the beach will continue to “grow” in an eastward direction gradually increasing the length of shoreline protected by the beach. The shoreline that is far enough away to not be influenced by the beach will continue to recede at approximately the long-term average annual recession rate. Terraprobe (2006) determined that the average annual recession rate in front of Meadowcliffe Drive is 1.2 metres per year. The recession rate will decrease moving westward until the point where the Bluffers Park East Beach provides full protection against wave induced bluff erosion. Figure 13 shows the estimated position of the bluff toe and top of slope in 100 years, based on an average 46 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
annual recession rate of 1.2 metres per year away from the influence of the beach. The planning horizon for the “Do-Nothing” scenario is 100 years.
Figure 13. The "Do - Nothing" alternative depicts the potential position of the bluff toe and crest predicted in 100 years. Source: Shoreplan Engineering Limited, 2007.
The cost of the “Do-Nothing” option was determined by reviewing the estimated 2009 market value of the affected properties and the potential cost of relocation or decommissioning affected infrastructure (e.g., gas lines, electrical, water and sewer connections). These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $27.6 million.
4.1.2 Preliminary Concept 1a – Headland Beach, Meadowcliffe Drive only
This preliminary concept consists of a cobble beach held in place by a series of shore parallel headlands and protects only the bluff fronting Meadowcliffe Drive. For this concept an access road is first constructed parallel to the shore, approximately 30 metres offshore of the existing toe of the bluff. Headlands in the order of 80 to 100 m long are then constructed in front of the access road. The spacing between the headlands can be varied but is in the order of 100 to 150 m. The headlands are connected to the shore via access roads and are protected with large armour stones. The toe of the stones is excavated into the lakebed to allow for the future downcutting of the cohesive profile. The area between the headlands will consist of rubble material covered with a layer of beach cobbles. The beach cobbles will be dynamically stable, meaning that the profile shape will adjust to different wave conditions and water levels. A conceptual drawing of this preliminary concept is presented in Figure 14.
The LTSSC is based on a 30 metre lakeward translation of the LTSSC determined from 2005 existing conditions by Terraprobe. The line was moved lakeward to account for the effect of constructing the shoreline protection 30 metres offshore of the toe of the bluff. It can be seen 47 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
that the projected LTSSC with shoreline protection indicates that the two easternmost dwellings on Meadowcliffe Drive (#2 and #10) will be threatened by erosion within the 100-year planning horizon. That threat can be eliminated through the use of a buttress.
Figure 14. Preliminary Concept 1a - Headland Beach. Meadowcliffe Drive only. Source: Shoreplan Engineering Limited, 2007.
Construction costs for Preliminary Concept 1a were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $7.4 million.
4.1.3 Preliminary Concept 1b – Headland Beach, bluff protection over full project site
Preliminary Concept 1b is the same as Preliminary Concept 1a except that Concept 1b protects the bluff over the full project site. A conceptual drawing is presented in Figure 15. The position of the LTSSC illustrated in the concept plan was determined by translating the LTSSC lakeward to account for proposed position of the protection structures, 30 m from the existing shoreline.
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Figure 15. Preliminary Concept 1b - Headland Beach, bluff protection over full project site. Source: Shoreplan Engineering Limited, 2007.
Construction costs for Preliminary Concept 1b were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $14.1 million.
4.1.4 Preliminary Concept 2a – Groyne/headland beach, Meadowcliffe Drive only
This preliminary concept also uses a headland retained beach but the headlands are constructed from groynes rather than the shore parallel structures used in concepts 1a and 1b. The groynes are higher in elevation than the offshore headlands and do not allow the beach material to move behind the heads of the groynes. This will allow finer beach gravel (20 mm diameter) to be used. Preliminary Concept 2a would only protect the area in front of Meadowcliffe Drive, stopping at the western most groyne (see Figure 16). The LTSSC accounts for proposed position of the protection structures, 30 m from the existing shoreline.
49 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Figure 16. Preliminary Concept 2a & 2b – Groyne/headland beach. Source: Shoreplan Engineering Limited, 2007.
Construction costs for Preliminary Concept 2a were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $8.2 million.
4.1.5 Preliminary Concept 2b – Groyne/headland beach, bluff protection over full project site
The shoreline geometry makes the use of goyne headland across the entire project site impractical. As such, Preliminary Concept 2b uses a boulder berm to protect the shore from the end of Concept 2a groynes to the Bluffers Park beach (see Figure 16). Shoreline protection in Concept 2a in Figure 16 stops at the western-most groyne. The position of the 50 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
LTSSC reflects the proposed position of the protection structures in relation to the existing shoreline.
Construction costs for Preliminary Concept 2b were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $11.7 million.
4.1.6 Preliminary Concept 3 – Breakwater (marine construction) + cobble beach (land construction)
This preliminary concept is similar to Concept 1 in that it uses shore parallel headlands to retain a cobble beach, but these headlands are not connected to the shore. This concept was developed to consider a protection system that could be constructed in part using marine access rather than land access. The access road and cobble beach would still be constructed from land but the headlands would be constructed using marine equipment. All material used in the construction of the headlands would be supplied by barge which would significantly reduce construction traffic to and from the immediate site, although the barges would likely be loaded at Bluffer’s Park. This option would therefore not reduce construction traffic in the general neighbourhood. The position of the LTSSC shown in Figure 17 takes into account that the protection structures are located 30 m offshore.
Figure 17. Preliminary Concept 3 - Breakwater (marine construction) + cobble beach (land construction). Source: Shoreplan Engineering Limited, 2007.
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Construction costs for Preliminary Concept 3 were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $23.1 million.
4.1.7 Preliminary Concept 4a – Headland/groyne (marine construction)
Preliminary Concept 4a consists of constructing a long groyne intended to retain a sand beach. The groyne would be built using marine supply and construction. The length of the groyne would be similar to the length of the Bluffer’s Park headland, measured in an offshore direction. The size of the beach retained by the groyne would be similar to the existing beach retained by Bluffer’s Park and the beach would be allowed to fill in naturally from the existing littoral drift. The position of the LTSSC was determined by translating the LTSSC lakeward to account for the 30 m offshore position of the proposed protection.
Construction costs for preliminary concept 4a were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $12.9 million.
4.1.8 Preliminary Concept 4b - Headland/groyne (marine construction) + rubble access road (narrow)
Preliminary Concept 4b is the same as 4a except that a groyne plus a narrow access road would be built. Constructing a narrow access road from rubble would stabilize the bluff until the beach filled in, but it would require land access and therefore some construction traffic. There would, however, be significantly less construction traffic than associated with concepts 1 and 2.
Construction costs for Preliminary Concept 4b were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $13.2 million.
4.1.9 Preliminary Concept 4c - Headland/groyne (marine construction) + sand beach (dredged)
Preliminary Concept 4c is the same as 4a and 4b except that for concept 4c the beach would be pre-filled using dredged material. Pre-filling the beach would minimize impacts associated with interrupting the littoral drift but the costs would be significant. Preliminary Concepts 4a, b and c are shown in Figure 18.
Construction costs for Preliminary Concept 4c were estimated using unit prices from recently tendered projects and may be considered to represent conditions in 2007. These cost estimates include a 15% contingency allowance, but are still only concept level cost estimates. Based on these assumptions this alternative is valued at $30.2 million.
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Figure 18. Preliminary Concept 4a, 4b + 4c – Headland/groyne (marine construction) + additional protection. Source: Shoreplan Engineering Limited, 2007.
5.0 EVALUATION OF PRELIMINARY ALTERNATIVE CONCEPTS
The baseline information was used to evaluate the alternative design concepts giving specific consideration to the positive and negative impacts on the existing physical, biological, socioeconomic, and cultural environments, as well as technical and engineering concerns. The results of the evaluation are outlined under the respective evaluation criteria categories below.
5.1 Evaluation Criteria
To ensure that the proposed solution best meets the project objectives, Shoreplan Engineering Limited, the public and agencies had several discussions to determine the most essential evaluation criteria in relation to the physical, biological, cultural, social, economic, and technical engineering elements. Each of the eight (8) preliminary concepts were evaluated with the criteria outlined in Section 5.1.1 to 5.1.4 and is summarized in Table 12. 53 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
5.1.1 Physical Criteria
To achieve the project objective of preserving or enhancing the ecological conditions of the shoreline, the following five physical evaluation criteria were considered as part of the evaluation of the alternatives:
• Consideration of sediment supply and movement • Design structures to withstand coastal processes • Preserve a unique landform, a section of the Scarborough Bluffs • Prevent or minimize negative updrift and downdrift impacts • Prevent or minimize negative water quality impacts
5.1.2 Biological Criteria
To achieve the project objective of preserving or enhancing the biological conditions of the shoreline and slope, the following four biological evaluation criteria were considered as part of the evaluation of the alternatives:
• Ensure no net loss of aquatic habitat • Preserve habitat linkages and corridors • Preserve unique aquatic and terrestrial habitats • Prevent or minimize negative impacts to existing vegetation
5.1.3 Cultural and Socioeconomic Criteria
As part of TRCA’s overall commitment to make the waterfront a place that achieves a wide range of objectives including waterfront access, and improvement of waterfront aesthetics, the evaluation of alternatives also considered the ability to satisfy the following objectives:
• Provide waterfront access to improve recreational use of shoreline • Improve waterfront aesthetics • Ensure compatibility with government initiatives • Determine capital and maintenance costs • Prevent or minimize negative impacts to historical and cultural features or resources • Prevent or minimize negative impact to the adjacent shoreline • Ensure public safety • Improve scenic views and vistas
5.1.4 Technical and Engineering Criteria
To achieve the project objective of creating a safe shoreline that supports the marine functions of Lake Ontario, the following six technical considerations were considered as part of the evaluation alternatives:
• Mitigate the instability and erosion of a section of the Scarborough Bluffs • Ensure no negative impacts to existing structures or infrastructure • Eliminate risk to life and property 54 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
• Diverse shoreline treatments • Construction of the shoreline protection (Scheduling)
The advantages and disadvantages of each of the preliminary concepts have been considered against the evaluation criteria developed by agencies, public and Shoreplan Engineering Ltd. The results of this evaluation are summarized in Table 12.
Table 12. Results of Evaluation Preliminary Concepts EVALUATION Alternative Advantage Disadvantage Effect on Environment CRITERIA PHYSICAL Sediment supply Do Nothing ● No impacts, as current conditions will be and movement maintained Concept 1a No significant impact as the current ● condition to sediment supply is insignificant Concept 1b Potential impact to beaches to the west due ● to disruption of sediment movement westward Concept 2a No significant impact as the current ● condition to sediment supply is insignificant Concept 2b Potential impact to beaches to the west due ● to disruption of sediment movement westward Concept 3 Potential impact to beaches to the west due ● to disruption of sediment movement westward Concept 4a Potential impact to beaches to the west due ● to disruption of sediment movement westward Concept 4b Potential impact to beaches to the west due ● to disruption of sediment movement westward Concept 4c Potential impact to beaches to the west due ● to disruption of sediment movement westward Coastal processes Do Nothing ● Shoreline continues to be at risk, as bluffs and updrift/ cannot withstand wave action downdrift impacts Concept 1a ● Designed to withstand coastal processes Concept 1b ● Designed to withstand coastal processes Concept 2a ● Designed to withstand coastal processes Concept 2b ● Designed to withstand coastal processes Concept 3 ● Designed to withstand coastal processes Concept 4a ● Designed to withstand coastal processes Concept 4b ● Designed to withstand coastal processes Concept 4c ● Designed to withstand coastal processes Unique landform Do Nothing ● Risk to Scarborough Bluffs Concept 1a ● Protects the shoreline Concept 1b ● Protecting an area of shoreline not required Concept 2a ● Protects the shoreline Concept 2b ● Protecting an area of shoreline not required Concept 3 ● Protecting an area of shoreline not required Concept 4a ● Protects the shoreline Concept 4b ● Protects the shoreline
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Concept 4c ● Protects the shoreline BIOLOGICAL Unique Do Nothing ● No change aquatic/terrestrial Concept 1a No significant impacts to ANSI-ES and ESA habitats ● #123 Concept 1b ● Disrupts ANSI-ES and ESA #123 Concept 2a No significant impacts to ANSI-ES and ESA ● #123 Concept 2b ● Disrupts ANSI-ES and ESA #123 Concept 3 ● Disrupts ANSI-ES and ESA #123 Concept 4a ● Disrupts ANSI-ES and ESA #123 Concept 4b ● Disrupts ANSI-ES and ESA #123 Concept 4c ● Disrupts ANSI-ES and ESA #123 CULTURAL AND SOCIOECONOMIC Waterfront access, Do Nothing ● No access aesthics, views and Concept 1a ● Increase access and potential improvement vistas Concept 1b ● Increase access and potential improvement Concept 2a ● Increase access and potential improvement Concept 2b ● Increase access and potential improvement Concept 3 ● Minimal access and improvement Concept 4a ● Minimal access and improvement Concept 4b ● Minimal access and improvement Concept 4c ● Increase access and potential improvement Government Do Nothing ● No change Initiatives – Concept 1a ● Potential improvement Strategies to improve the Concept 1b ● Potential improvement waterfront Concept 2a ● Potential improvement Concept 2b ● Potential improvement Concept 3 ● No improvement Concept 4a ● No improvement Concept 4b ● No improvement Concept 4c ● Potential improvement Capital and Do Nothing ● Continual costs to relocate residents and maintenance costs infrastructure Concept 1a ● Economical Concept 1b ● Cost prohibitive Concept 2a ● Economical Concept 2b ● Cost prohibitive Concept 3 ● Cost prohibitive Concept 4a ● Cost prohibitive Concept 4b ● Cost prohibitive Concept 4c ● Cost prohibitive Public Safety Do Nothing ● Risk to public Concept 1a ● Minimal risk to public Concept 1b ● Minimal risk to public Concept 2a ● Minimal risk to public 56 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Concept 2b Risk to public as the shoreline is in close ● proximity to eroding bluff Concept 3 Risk to public as the shoreline is in close ● proximity to eroding bluff Concept 4a Risk to public as the shoreline is in close ● proximity to eroding bluff Concept 4b Risk to public as the shoreline is in close ● proximity to eroding bluff Concept 4c ● Minimal risk to public TECHNICAL Erosion and Slope Do Nothing ● Will not preserve the bluffs Stability Concept 1a Will stabilize and protect properties at risk ● minimal erosion to the bluffs Concept 1b Protects properties not at risk but will ● stabilize and minimize erosion to the bluffs Concept 2a Will stabilize and protect properties at risk ● minimal erosion to the bluffs Concept 2b Protects properties not at risk but will ● stabilize and minimize erosion to the bluffs Concept 3 Protects properties not at risk but will ● stabilize and minimize erosion to the bluffs Concept 4a Will stabilize and protect properties at risk ● minimal erosion to the bluffs Concept 4b Will stabilize and protect properties at risk ● minimal erosion to the bluffs Concept 4c Will stabilize and protect properties at risk ● minimal erosion to the bluffs Existing structures Do Nothing ● Risk to five (5) residential dwellings and and infrastructure associated infrastructure Concept 1a Potential to eliminate risk to dwellings and ● infrastructure Concept 1b Potential to eliminate risk to dwellings and ● infrastructure Concept 2a Potential to eliminate risk to dwellings and ● infrastructure Concept 2b Potential to eliminate risk to dwellings and ● infrastructure Concept 3 Potential to eliminate risk to dwellings and ● infrastructure Concept 4a Potential to eliminate risk to dwellings and ● infrastructure Concept 4b Potential to eliminate risk to dwellings and ● infrastructure Concept 4c Potential to eliminate risk to dwellings and ● infrastructure Loss of life and Do Nothing Risk to severely reduce size of properties as property ● LTSCC recedes Concept 1a Potential to reposition LTSSC to reduce loss ● of property Concept 1b Potential to reposition LTSSC to reduce loss ● of property Concept 2a Potential to reposition LTSSC to reduce loss ● of property Concept 2b Potential to reposition LTSSC to reduce loss ● of property Concept 3 Potential to reposition LTSSC to reduce loss ● of property Concept 4a Potential to reposition LTSSC to reduce loss ● of property Concept 4b Potential to reposition LTSSC to reduce loss ● of property Source: TRCA, 2009. 57 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
5.2 Public Evaluation of Preliminary Alternatives Concepts
CLC meeting #2 was held on February 7, 2007 at 1 Eastville Avenue, and was attended by several staff from TRCA, staff from Shoreplan Engineering Ltd., Councillor Brian Ashton, several local property owners, representatives for Lorenzo Berardinetti, M.P.P., a representative from the Ontario Heritage Trust, and a City of Toronto staff member. Shoreplan Engineering Ltd. (Shoreplan) presented nine alternative design concepts, and provided rough cost estimates for each of the proposed options. A comment form was distributed to the CLC Committee to provide feedback on each of the options presented, to select the preferred design concept, and to assess the importance of the evaluation criteria for each of the concepts presented.
It was communicated to the CLC members that the rating of the criteria would have an impact on the overall evaluation of the preferred option. Further it was explained that the rating of each individual criterion may not be held on par, based on project specific constraints as identified on a project by project basis. The evaluation is based on the screening criteria mandated in the Class EA document (Conservation Ontario, 2002).
In order to assess the relative importance of the evaluation criteria, CLC members were asked to rank each criterion on a scale of 1 to 5, 5 being the most important, 1 being the least important, NC being “no comment”. The results of the rankings from the five (5) returned comment sheets are documented in Table 13 and illustrated in Figure 19. Criteria listed as “other” were specific recommendations by CLC members.
Table 13. Rankings of Proposed Evaluation Criteria. Biological 5 4 3 2 1 NC Total Weight Median Aquatic Habitat 1 3 4 3.5 Habitat Linkages or Corridor 4 4 4.0 Terrestrial Habitat 1 3 4 3.3 Vegetation 2 1 1 4 3.8 3.65 Cultural and Socioeconomic Total Weight Median Access to Water 2 1 1 4 3.0 Appearance 1 3 4 3.5 Compatibility with Government Policies 2 2 4 4.0 Costs (Capital) 3 1 4 4.8 Costs (Maintenance) 1 1 2 4 4.0 Historical and Cultural Features or Resources 2 1 1 4 3.8 Impact on Adjacent Shoreline 4 4 4.0 Public Safety 1 1 2 4 4.5 Support of Park Uses 2 2 4 4.0 Views and Vista 4 4 4.0 4.0 Physical Total Weight Median Littoral Drift (Sediment Supply and Movement) 1 3 4 4.3 Other Coastal Processes (Wave Activity) 1 3 4 4.3 Unique Landforms (e.g. Dunes) 1 1 2 4 3.5 Updrift/Downdrift Impacts 3 1 4 3.8 Water Quality and Circulation 1 3 4 4.3 4.3 Technical and Engineering Total Weight Median Diversity of Shoreline Treatments 1 3 4 4.3 Erosion Mitigation 3 1 4 4.8 Existing Structures or Infrastructure 1 1 2 4 4.5 Risk to Life and Property 4 4 5.0 Scheduling (Phasing) 2 1 1 4 4.3 4.5 58 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
Other Total Weight Median Add bluff stabilization methods 1 1 4.0 Pedestrian linkage (trails) 1 1 4.0 4.0 Source: TRCA, 2009.
Results of Proposed Evaluation Criteria
5
4 Biological
Cultural / Socioeconomic 3
Physical 2
maximum of 5) of maximum Technical / Engineering 1 Median Values (out of a of (out Values Median Other
0 Evaluation Criteria Categories
Figure 19. Results of the Evaluation Criteria by category as ranked by CLC members, expressed as median values. Source: TRCA, 2009.
As illustrated in Table 13 and Figure 19 the technical and engineering (e.g. erosion mitigation, risk to life and property) and physical (e.g. coastal processes, unique landforms, water quality) criteria were considered to be of greatest importance by the CLC members.
Furthermore, the results of the returned ranking forms also indicated that the preferred design concept selected by the CLC members was the Headland Beach Concept (1a), which provides protection to Meadowcliffe Drive only. TRCA received several of the following comments on the forms:
• Headland Beach – Meadowcliffe Drive (Concept 2a) is the only concept considered to be the most practical in terms of cost, property protection, and beach access for the public. • Headland Beach – full site (Concept 1b) is effective but costly. The member has reservations about implementing shoreline protection for the entire project limits since the majority of the erosion is concentrated at the Meadowcliffe Drive shoreline. • Groyne Retained Sand Beach – Pre-fill Beach (Concept 4c) is too expensive. • The shoreline from Bluffers Park to Port Union should be connected in order to facilitate pedestrian recreational use and future TRCA shoreline protection construction or maintenance.
The documentation of this CLC meeting is contained in Appendix C.
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5.3 Agency Evaluation of Preliminary Alternative Concepts
Once the CLC’s evaluation of each approach was reviewed and discussed, TRCA completed a further examination of each of the preliminary concepts. This included an extensive examination of the types and extents of impacts, both positive and negative, that each alternative method would have, including but not limited to:
• The significance of the expected environmental effects • The degree of the effectiveness of the method • The extent of the technical feasibility • The magnitude of costs
5.3.1 The “Do-Nothing” Alternative
The environmental effects of a “Do-Nothing” approach relates to the potential long-term affects of shoreline erosion on the terrestrial and cultural environment. These predicted problems are largely associated with the ongoing loss of shoreline. Under the “Do-Nothing” alternative erosion will continue along the shoreline east of the beach retained by the Bluffers Park headland.
If left unprotected the crest of the bluffs is anticipated to recede by approximately 48 m within the next 100 years. This loss of land would place approximately twelve (12) residential dwellings in immediate risk and would affect several other properties by severely reducing the amount of overall property. A heritage property, municipal roadway and supporting stormwater drainage system would also be affected by the predicted rate of erosion.
Although the “Do-Nothing” alternative would not require any financing up front, ongoing costs would be required to relocate servicing, and replace municipal infrastructure. Additional costs would be required to relocate or replace the affected residences. Therefore this alternative is not considered technically feasible due to the risk to public infrastructure and property.
5.3.2 Preliminary Concept 1a – Headland Beach, Meadowcliffe Drive only
This preliminary concept consists of a cobble beach held in place by a series of shore parallel headlands and protects only the bluff fronting Meadowcliffe Drive. This design would not impact or interrupt the existing littoral drift. The sediment budget data showed that, on average, less than 5,000 cubic metres per year of sediment is currently transported to the site. The sediment transport pathways analysis showed that the existing wave climate is capable of transporting the full sediment supply past the site in water depths of approximately 2.5 metres below datum, and deeper which corresponds to the deepest toe depth of the headlands.
Regional impacts of each proposed alternative, including this concept, relates to the elimination of sources of sediment transport material due to shoreline protection. The shoreline protection works will reduce the amount of sediment transported by littoral drift from the Meadowcliffe Drive area. This will significantly reduce the amount of sediment being supplied to the fillet beach at Bluffer’s Park. However, as sand is bypassing the easternmost headland at Bluffer’s Park, but not the entire park itself, reducing the sediment supply will not have a
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significant impact. Since Bluffer’s Park is considered to be a complete littoral barrier downdrift affects will not be noticed.
From a recreational standpoint this is a good concept as the shore protection and associated maintenance road would provide public shoreline access for passive waterfront recreation. Furthermore, with the shoreline protection in place, southwest waves would transport sediment onto the shoreline east of Bluffer’s Park. Ultimately, this process would cause the beach to expand during low water level conditions.
This solution is particularly desirable with consideration of the financial costs, as the design is the most economical to implement. Moreover, this alternative is the most technically feasible with the least impacts to the natural, cultural and socioeconomic environments.
5.3.3 Preliminary Concept 1b – Headland Beach, bluff protection over full project site
This preliminary alternative is similar to Concept 1a, however this design will be constructed along the full project site. As the Meadowcliffe Drive area is the only area of shoreline with active erosion caused by wave action at the toe of the bluff, additional protection to the area of shoreline fronted by beach is not considered warranted. The protection of the additional area to the west of Meadowcliffe Drive unnecessarily increasing the amount of lakefilling required, consequently increasing the loss of aquatic habitat. Moreover, this area is designated a life science ANSI and ESA which would be negatively altered following protection. Therefore, this alternative is not considered a viable option due to the significant negative impacts on the environment.
5.3.4 Preliminary Concept 2a – Groyne/headland beach, Meadowcliffe Drive only
This preliminary concept also uses a headland retained cobble beach but the headlands are constructed from groynes rather than the shore parallel structures used in concepts 1a and 1b. The groynes are higher in elevation than the offshore headlands and do not allow the beach cobbles to move behind the heads of the groynes. The groynes will allow finer beach fill to be used although it would still be stone material. The higher elevation and proposed material of the shoreline protection will have a considerable impact to the aesthetics of the shoreline. 5.3.5 Preliminary Concept 2b – Groyne/headland beach, bluff protection over full project site
This preliminary alternative is similar to Concept 2a, except the headland retained cobble beach would be constructed along the full study area. As previously noted with option 1b, the benefit of lakefilling the area adjacent to Cudia Park is not considered to outweigh the negative impacts and costs associated with the increased shoreline protection.
5.3.6 Preliminary Concept 3 – Breakwater (marine construction) and cobble beach (land construction)
This preliminary concept is similar to Concept 1 in that it uses shore parallel headlands to retain a cobble beach, but these headlands are not connected to the shore. This concept was developed to consider a protection system that could be constructed using marine and land access. The access road and cobble beach would still be constructed from land but the headlands would be constructed using marine equipment. All material used in the construction of the headlands would be supplied by barge which would significantly reduce construction 61 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
traffic to and from the immediate site, although the barges would likely be loaded at Bluffer’s Park. This option would therefore not reduce construction traffic in the general neighbourhood. Additionally it should be noted that marine construction options significantly increases the cost of construction.
From a recreational standpoint, the proposed offshore breakwater would be considered a negative impact as it is anticipated marine construction would disrupt boaters launching from or based at Bluffer’s Park. Furthermore, the community members would not be content with the considerable alteration to the natural aesthetics of the shoreline.
The excessive cost of construction and the negative impacts perceived by constructing offshore breakwaters causes this alternative to be eliminated as a viable solution.
5.3.7 Preliminary Concept 4a – Headland/groyne (marine construction)
The advantage of 4a is that it reduces the amount of materials required for construction and reduces the impacts associated with construction traffic. However, these advantages are outweighed by the impact of marine construction on recreational boating (see Section 5.3.6). Moreover this concept requires more time than the other options to effectively stabilize the eroding slope as the creation of the beach is dependant on the sediment supply that can be generated from the existing littoral drift. As discussed in Section 5.3.2, there is a low sediment supply along the Meadowcliffe shore sector. As such it would take many years for the beach to develop. Development of the beach is critical to influencing the stabilization of the adjacent bluff. Consequently, this option is not viable as there would be additional loss of property and potential risk to residential dwellings along the crest of the bluff during the period in which the beach is forming.
5.3.8 Preliminary Concept 4b - Headland/groyne (marine construction) and rubble access road (narrow)
Preliminary Concept 4b is the same as 4a with the exception that a groyne plus a narrow access road would be built. Constructing a narrow access road from rubble would stabilize the bluff until the beach forms, but it would require land access and therefore some construction traffic. There would, however, be significantly less construction traffic than associated with concepts 1 and 2 as the amount of material required for construction is reduced.
The construction of an access road would stabilize the shoreline and prevent the erosion to the slope and similar to concept 4a, the beach will be naturally filled by the existing littoral drift. However, the narrow access road and naturally filled beach would not be accessible to the community due to the associated safety risk with bluff instability and potential for landslides.
With consideration for the rationale identified in Section 5.3.6 in addition to the limited community accessibility to the shoreline this alternative has been eliminated as a viable option.
5.3.9 Preliminary Concept 4c - Headland/groyne (marine construction) and sand beach (dredged)
This alternative is similar to Concept 4a and 4b, however the beach would be pre-filled using dredged sand material. Pre-filling the beach would minimize any impacts associated with the 62 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010
littoral drift. Furthermore, from a recreational standpoint the creation of a sand beach would be considered highly attractive and valuable to the community. While this concept would increase the recreational use and aesthetics of the shoreline, the costs are almost three times higher than all other options. Based on cost this option has been eliminated.
6.0 PREFERRED ALTERNATIVE
The results of the evaluation of alternatives led to the preliminary identification of Concept 1a (headland beach protecting Meadowcliffe Drive only) as the Preferred Alternative. Selection of this option as the Preferred Alternative was based primarily on the following reasons: • Provides an attractive, diverse habitat • Consistent with proven shoreline protection utilized along this section of waterfront • Aesthetically pleasing and resembles shoreline to the east of Bellamy Ravine • Potential to improve terrestrial and fish habitat • Most cost efficient of all options • Protects toe of bluffs currently impacted by wave erosion
Based on the position of the LTSSC with the implementation of Concept 1a it was determined that refinement of the alternative was required and is described in Section 6.1.
6.1 Refinement of the Preferred Alternative
As previously noted, the shoreline protection proposed as part of the Preferred Alternative will stop the toe erosion at the base of the bluffs, however the position of the LTSSC will continue to recede and may eventually threaten human life and property at the eastern portion of this shoreline sector at risk (see Figure 20). As the objective of the project, is to protect human life and property from the hazards of erosion and slope instability, a buttress at the base of the bluffs at the east end of the shoreline sector has been proposed as part of the remedial works to ensure long-term protection of the affected properties. The proposed buttress would be constructed using earth, rock or rubble fill from the toe of slope to elevation 84 m, with an inclination of 2.5:1 (H:V). The buttress would have a horizontal bench with a width of 25 m and extend 40 m southward from the existing slope toe.
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Figure 20. LTSSC position in relation to properties 1, 2 and 10 Meadowcliffe Drive. Source: Terraprobe, 2009.
In accordance with the Class EA planning and design process, once the Preferred Alternative method is selected it is to be subjected to a more detailed study of the net impacts likely to be associated with its implementation, known as a detailed environmental analysis. A further determination can then be made regarding how the potential net negative impacts can be best dealt with at the detailed design level.
6.2 Description of the Preferred Alternative
The Preferred Alternative is based on Preliminary Concept 1a, the headland beach protecting Meadowcliffe Drive only. Appendix B shows a plan and typical sections for the preferred alternative. It consists of a cobble beach retained by 4 headlands. The end headlands will be constructed like “L” groynes, with armour stone along the outside of the headlands. The western-most headland has a small spur on its west side to help retain any sand transported alongshore from the Bluffer’s Park beach. The two central headlands will constructed from shore but only the shore-parallel component of those headlands will be armoured. The temporary access roads out to the headlands will eventually be covered with beach cobbles.
Construction will start with a 10 metre wide access road located approximately 30 metres offshore of the existing bluff. The offshore side of the headlands will be located near the 72.0 metre contour line. The toe will be excavated into the lakebed to allow for the future downcutting of the cohesive profile. The two central headlands will be approximately 60 metres long at the crest and the spacing between the headlands will be in the order of 100 to 150 metres. Beach cobble sizes will be determined during detailed design. The beach cobbles will be dynamically stable, meaning that the profile shape will adjust to different wave
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conditions and water levels but overall will be stable. The underlying rubble material will not be exposed during these normal profile adjustments.
Following construction of the shoreline protection TRCA will monitor recession of the slope on an annual basis to determine the need for further works which may include a buttress as conceptually illustrated in Figure 20.
Once the preferred concept was chosen the Class EA process continued to the Detailed Environment Analysis stage, described further in Section 7.0 of this report.
7.0 ENVIRONMENTAL SCREENING OF PREFERRED ALTERNATIVE
7.1 Detailed Environmental Analysis of the Preferred Alternative
To complete the detailed environmental analysis of the preferred alternative, the information collected for the baseline inventory is examined in greater detail to confirm potential impacts, refine methods of mitigation, and identify any unforeseen impacts. The evaluation of impacts includes both temporary impacts during construction of the undertaking, and permanent impacts due to operation and maintenance of the undertaking after construction. Table 14 screens the potential negative and positive effects of the proposed undertaking on the environment during construction and maintenance phases. It includes the consideration of the magnitude, geographic extent, duration, frequency, permanence or reversibility and ecological context of the effects, as well as proposed mitigation measures and any residual effects.
Environmental components that have been identified as potentially having an effect on the environment, both positive and negative, are discussed herein. Those components determined to be not applicable (n/a) as identified in Table 14, have been omitted from further discussion.
65 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010 Rating of Potential Effects -L NIL +L +M +H NA Comments Physical ● Monitoring program in place to maintain integrity of headlands and dynamic beaches. ● ● Construction will not occur within ANSI – ES area. ● ● ● ● ● Construction will not occur within the ESA areas. ● Mitigative measures will be taken to minimize impacts of equipment use during construction and operation. ● Construction will not impact outfall located within the Bellamy Ravine. ● Mitigative measures will be taken to minimize impacts of equipment use during construction and operation. ● Design considers effect of extreme lake levels, storm influences, and wave conditions. ● Design considers low lake levels. ● All construction to be carried out at the toe of the bluff. ● ● No significant impacts are expected. ● Minor local impacts are expected with wave sheltering and reflections. ● Mitigative measures will be in place during construction to protect water quality. ● Only clean aggregates and/or rubble will be used in construction. ● ● ● ● See Unique Landforms. ● Biological ● Proposed remedial work will improve terrestrial habitat currently threatened by erosion. ● Project will result in an improvement to habitat linkages and corridors. ● Proposed remedial work will help with the re-establishment vegetation on the bluff face. ● Construction will not occur within an ESA. ● Project will improve nearshore habitat conditions for local fishery. DFO will approve compensation plan prior to construction. ● No species of concern located within the project area. ● Restoration plan will inclue native vegetation wherever feasible. ● In the long-term, wildlife habitat will improve as vegetation growth increases on the bluff face. ● Rating of Potential Effects -L NIL +L +M +H NA Comments ● ● No significant impacts are expected.
Cultural ● ● ● ● ● ● Temporary disruption only. ● Access to shoreline improved in the long-term. ● Bluffs will lose their “majestic” cliff-like look. ● Project restricted to the base of the bluffs. ● ● ● ● Socioeconomic ● Temporary disruption only. ● ● Protects existing infrastructure and services. ● Shoreline protection and access road will provide pedestrian access along the shoreline. ● Protection work will reduce or eliminate further loss of property and protect property values along Meadowcliffe Drive. ● ● ● Engineering/Technical ● Proposed works will stop erosion at the toe of the Bluffs. ● Overall effect on the existing beach will not be noticeable. ● ● Bluffs will erode to a stable angle of repose thus increasing slope stability. ● Provides protection for existing structures in the long-term. ● Slope instability will be reduced. ● ), neutral (NIL) or positive (+) and rating them as relatively high (H), medium (M), low (L) or not applicable (NA). From Conservation Ontario, Class Environmental Assessment for Remedial
7.1.1 Physical Environment
Unique Landforms The Scarborough Bluffs are the most significant unique landform within the study area. The bluffs have been eroding at an average rate of 0.45 metres per year since the 1900s. It is speculated that this erosion has been accelerated by the historic removal of aggregate materials such as gravels, cobbles and boulders which were once found in abundance on the shoreline and nearshore waters.
The project will result in the preservation and enhancement of gravel, cobble and sand beaches which mimics the natural protection once afforded to the Scarborough Bluffs. The proposed shoreline design will protect the toe of the bluffs, allowing the over-steepened slopes to establish a more natural angle and increase the growth of vegetation in this section of the bluffs. As the bluffs will be protected as a result of the preferred alternative, no significant impacts are expected on the unique landforms within the study area.
Area of Natural and Scientific Interest – Earth Science (ANSI-ES) The preferred alternative will only be protecting below Meadowcliffe Drive, as such there is no remedial work proposed for the ANSI -ES identified at Cudia Park. Therefore no significant impacts are expected.
Environmentally Sensitive / Significant Areas (Physical) The preferred alternative will be shoreline protection along the entire base of the Meadowcliffe Drive, plus bank stabilization along the most eastern portion, below 1, 2 and 10 Meadowcliffe Drive; as such the Sequence of the Scarborough Bluffs (ESA #123) is only included in the project area that will undergo bank stabilization. TRCA recognizes that the bluffs within the study area are significant and any works conducted along this sector will be conducted to minimize and mitigate potential negative impacts.
Air Quality The trucks required to bring aggregate and fill material for the construction of the remedial works can increase dust in and around the project site. In order to minimize the amount of dust generated by construction, mud build up on the roads surrounding the site will be removed by street sweepers when required and trucks transporting earth fill to the site will be covered with a tarpaulin. Dust polymers approved by the Ministry of the Environment will be applied along TRCA service access road to minimize the disturbance of dust.
Efforts will be taken to transport construction materials to the site and stockpile them to avoid having to use the access roads during dry summer months when dust problems are exacerbated. Furthermore, truck drivers will also be reminded by the on-site construction supervisor of the City of Toronto’s anti-idling bylaw. By taking these precautionary measures the effect of the project on local air quality will be limited and temporary, therefore causing no significant residual impacts.
Agricultural Tile or Surface Drains The preferred alternative will not have any impact on the outfall located within the Bellamy Ravine which is located just east of the project area.
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Noise Levels and Vibrations The construction of the shoreline protection will require heavy machinery and the import of aggregate and fill material. Earth movers and trucks in particular will cause a temporary increase in noise and vibration.
During the construction of the shoreline protection of the Meadowcliffe Drive sector there is anticipated to be minimal noise and vibration. As enforced on all TRCA project sites, all construction trucks will meet manufacturer sound attenuation specifications; and the project site will be in compliance with time prohibitions for delivery of materials and operation of construction equipment per the Toronto Municipal Code, Chapter 591. Furthermore, other applicable noise protocols will be enforced to diminish the potential for noise from construction activity.
In regards to the potential vibration from the construction activity, TRCA contacted an engineering firm, Terraprobe Limited with professional experience to comment about the effects of vibration on the bluffs (refer to Appendix D to view a copy of the letter). Terraprobe stated that the vibration from the construction would not have any significant adverse impacts on the stability of the Scarborough Bluffs. At any time during construction if there is any question of the stability of the bluffs due to the vibration of construction activity TRCA will respect the need for an engineering firm to complete vibration monitoring. Furthermore, to limit the effect of noise and vibrations caused by truck and equipment operation, construction will occur Monday to Friday during regular working hours, from 7:30 am to 4:30 pm, to avoid disturbing the area residents during their leisure time. The effect of construction equipment and trucks on noise and vibration will be minimized and temporary in duration; therefore no significant residual impacts are expected.
Water Flow Regime The construction of the shoreline protection works will not alter the water levels in Lake Ontario.
Existing Surface Drainage / Groundwater Seepage / Groundwater Recharge and Discharge Zones The construction of the Preferred Alternative will not alter the existing surface drainage from the tablelands along Meadowcliffe Drive. Groundwater seepage along the Meadowcliffe Sector was documented to be along the upper bluff face from the top of the slope crest to approximately 15 m below the crest. As the shoreline protection works will be at the base of the sector it will not impact or change the groundwater seepage zones. However, as the preferred alternative of the shoreline protection incorporates bank stabilization work below 1, 2 and 10 Meadowcliffe Drive there will be a drainage system implemented in this area of the Meadowcliffe Sector to minimize any impacts to the groundwater seepage zones.
Littoral Drift The potential effects of the undertaking on littoral drift can be described in terms of local and regional impacts. Local impacts are those caused by the proposed structures interference with littoral transport. Regional impacts are generally associated with the loss of littoral transport by eliminating or reducing a historic source of material or permanently trapping littoral material.
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The proposed erosion control works will not impact or interrupt the existing littoral drift. The sediment budget data showed that, on average, less than 5,000 cubic metres per year of sediment is currently transported to the site. The sediment transport pathways analysis showed that the existing wave climate is capable of transporting the full sediment supply past the site in water depths of approximately 2.5 metres below datum, and deeper which corresponds to the deepest toe depth of the headlands.
Regional impacts of the proposed undertaking relate to the elimination of sources of sediment transport material due to shoreline protection. The shoreline protection and slope stabilization works will reduce the amount of sediment transported by littoral drift from the Meadowcliffe Drive area. This will significantly reduce the amount of sediment being supplied to the fillet beach at Bluffer’s Park. However, as sand is bypassing the easternmost headland at Bluffer’s Park, but not the entire park itself, reducing the sediment supply will not have a significant impact. Since Bluffer’s Park is considered to be a complete littoral barrier downdrift affects will not be noticed.
Minor adjustment is anticipated to the plan shape of the fillet beach once the western-most headland is constructed.
Wave Climate – Other Coastal Processes The proposed design was developed to mimic natural coastal processes at the site. The beaches have been designed to be dynamic in nature, meaning that under varying wave and water level conditions, the beaches will vary in width, length above water and in profile.
The size and placement of the armourstone was calculated with consideration for the existing wave climate including wave height, wave spectra, wave refraction, duration of exposure, water depth, water fluctuation, and downcutting of the foreshore. The shoreline design will withstand or self-adjust to wave conditions; therefore no significant residual effects are anticipated.
Water Quality During construction there is potential for increased turbidity of the nearshore waters adjacent to the project site. Sediments may be carried into the lake indirectly via surface runoff or directly through the deposit of sediment laden materials during the lakefill process. To ensure that turbidity is not affected by soils used during the lakefilling process, unconfined materials will be used only when a protective rubble core isolates the fill area from the open lake. The potential effect of lakefilling operations on water clarity will be further mitigated by ensuring that TRCA lakefilling activities are undertaken in accordance with its Erosion and Sediment Control Guidelines for Construction (TRCA, 1994), and in compliance with TRCA’s Lakefill Quality Control Program (LQCP).
The LQCP is designed to protect water quality from the potential use of unsuitable soil or fill materials during lakefilling operations. No significant residual impacts are anticipated as the above described measures will eliminate the risk of introducing contaminants and mitigate the potential affects of construction on the turbidity of nearshore waters.
The erosion control works will eliminate erosion of the bluffs caused by wave action. As a result there will be a reduction of sediment entering the lake which will have a positive affect on water quality.
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Soil/Fill Quality Activities associated with the construction of the project are not expected to have any impact on soils or sediment quality. No existing contamination has been identified on-site. Only soils approved under TRCA’s LQCP will be imported to the site to maintain the quality of the local soils. Due to these practices, no significant impacts are expected.
Existing Transportation Routes The potential affect of the project on existing transportation routes as it relates to the proposed construction access route is addressed in Section 9.0.
7.1.2 Biological Environment
Wildlife Habitat Construction activities are expected to temporarily displace wildlife during site preparation and shoreline protection. Activities are expected to temporarily displace resident wildlife only. All work will be scheduled to avoid critical habitat, therefore no residual impacts are anticipated. Overall, the wildlife habitat will improve as a result of the habitat compensation measures.
Habitat Linkages or Corridors The steep slopes of the Scarborough Bluffs are largely untouched by the adjacent residential communities creating a continuous habitat linkage across the north shore of Lake Ontario from Highland Creek to the central waterfront. The proposed works will only encroach on the most eastern portion of the bluffs along the Meadowcliffe Sector and will provide wildlife with improved access to the lake. Therefore the project will result in an improvement to habitat linkages and corridors.
Significant Vegetation and Communities The proposed shoreline and slope stabilization of the Meadowcliffe Sector will allow vegetation to re-establish. All disturbed areas will be restored. Overall, the wildlife habitat in project area will be improved.
Environmentally Significant Areas – Biological TRCA recognizes that natural habitat areas within the study area are significant and any works conducted along this sector will be conducted to minimize and mitigate potential negative impacts. The Preferred Alternative will be shoreline protection along the entire base of the Meadowcliffe Drive, plus bank stabilization along the most eastern portion, below 1, 2 and 10 Meadowcliffe Drive; as such ESA #123 will not be impacted.
Fish Habitat During lakefilling operations fish will be temporarily displaced from the shoreline to avoid noise or localized turbidity. To mitigate the alteration, disruption or destruction of fish habitat resulting from the release of sediments or contaminated lakefill into Lake Ontario, TRCA will rely on employing best environmental management practices (BEMPs) during construction. These practices are outlined in TRCA’s Erosion and Sediment Control Guidelines for Construction and LQCP.
The lakefilling associated with the shoreline protection will likely result in the harmful alteration, disruption or destruction of fish habitat (HADD). To ensure adequate compensation for this
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HADD, TRCA will work with Fisheries and Oceans Canada (DFO) to develop a fish habitat compensation plan which will include:
• Creation of cobble/gravel beaches • Creation of offshore reefs and shoals • Wetland creation at an off-site location along the waterfront
A fish habitat compensation plan will be developed using the Habitat Alteration Assessment Tool and will require the review and approval of Fisheries and Oceans Canada. The aquatic enhancements planned for the project will contribute to increased aquatic habitat productivity to ensure that the project has no significant residual impacts on fish or fish habitat.
Species of Concern TRCA recognizes the presence of provincially and regionally uncommon plant species within the Cudia Park/Bellamy Ravine section of the Scarborough Shoreline. The shoreline protection and bank stabilization works will be limited to the base and most eastern portion of the Meadowcliffe Sector Bluffs. There are no L1 or L2 species located within the project area, therefore no significant impacts are expected to any species of concern.
Exotic/Alien and Invasive Species Only native species, indigenous to the north shore of Lake Ontario will be used during implementation of the project. As the project will not introduce or encourage exotic or invasive plant species no significant residual impacts are expected.
Wildlife/Bird Migration Patterns Construction activities are expected to temporarily displace wildlife during site preparation and shoreline protection. Activities are expected to temporarily displace resident wildlife only. No residual impacts are anticipated. In the long-term, the wildlife habitat will improve as vegetation growth increases on the bluff face.
Wildlife Population The project will not have any negative effects on wildlife population within the project area.
Microclimate The proposed works will not have an effect on the microclimate.
Areas of Natural Scientific Interest - Life Science (ANSI-LS) The Preferred Alternative will only be protecting below Meadowcliffe Drive, as such there is no remedial work proposed for the ANSI -LS identified at Cudia Park. Therefore no significant impacts are expected.
7.1.3 Cultural Environment
Traditional Land Uses The proposed work will not have any effect on traditional land uses.
Riparian Uses The proposed work will require acquisition of riparian rights along Meadowcliffe Drive to ensure that the remedial works are constructed and maintained on public land. The affected riparian
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area is located outside of the area currently accessible to the private landowners; as such the Preferred Alternative will not have any negative impact on riparian uses.
Recreational or Tourist Use of Water Body and/or Adjacent Lands The project will not have an effect on Bluffer’s Park which is located west of the project area.
Recreational or Tourist Use of Existing Shoreline Access Locations TRCA is aware that many members of the communities along the Scarborough Bluffs utilize the network of shoreline service roads to gain access to the shoreline. However, as the primary purpose of these service roads is to provide TRCA with vehicle and equipment access to the shoreline, TRCA must restrict public access during periods of active operation in order to ensure public safety. While service roads are not intended as a formal pedestrian trail, TRCA understands the importance of maintaining this informal public use. As such TRCA is committed to allowing the public access to affected sections of the service road for recreational purposes on public holidays, weekday evenings (between 5:00 pm and 7:30 am) and weekends (from 4:30 pm no Friday to 7:30 am on Monday). TRCA will also endeavour to minimize disruption to public use of the service road during warm weather months from April to October. Moreover, TRCA will commit to provide the public with formal notification of construction or maintenance activities to improve communication with the community.
Aesthetic or Scenic Landscapes or Views The implementation of the shoreline protection works will, in the long run, affect the shape and look of the Scarborough Bluffs along the Meadowcliffe Drive Sector. The Scarborough Bluffs will lose their “majestic” cliff-like look.
Archeological Resources, Built Heritage Resources and Cultural Heritage Landscapes Since the project is restricted to the bluffs at the base of Meadowcliffe Drive there are no archeological sites within the project area.
7.1.4 Socioeconomic Environment
Surrounding Neighbourhood or Community The surrounding neighbourhood or land uses will not be affected by the proposed works.
Surrounding Land Uses or Growth Pressure The surrounding land uses or growth pressure will not be affected by the proposed works.
Existing Infrastructure, Support Services, Facilities The proposed works will reduce the current rate of erosion that is occurring in this area and will aid in the protection of the homes located on Meadowcliffe Drive. All construction will occur at the toe of the bluffs and therefore there are no anticipated impacts to any structures on the tableland as a result.
Pedestrian Traffic Routes Presently, the Meadowcliffe Sector is not accessible for pedestrian or vehicle traffic. The access road to be constructed and maintained as part of the proposed shoreline protection will in future however, provide pedestrian shoreline access. Section 9.0 provides further description of potential impacts and benefits related to the project as it relates to construction access.
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Property Values or Ownership The proposed undertaking is not likely to have an adverse effect on property values for the homeowners along Meadowcliffe Drive. Conversely, the shoreline protection work is expected to protect property values at the subject site.
7.1.5 Engineering/Technical
Rate of Erosion in Ecosystem Based on historic erosions, it is estimated that erosion will continue at an average rate of 1.2 metres per years until the lower bluff reaches a stable slope of 2.5: 1.0 (horizontal: vertical) and the upper 30 metres obtains a stable slope of 1.5: 1 (horizontal: vertical). A buttress proposed at the eastern extent of the project site will stabilize the slope to halt erosion affecting 2 and 10 Meadowcliffe Drive. The long-term stable slope crest position is illustrated in Figure 14 and Figure 20.
Sediment Deposition Zones in Ecosystem The Preferred Alternative will result in a minor adjustment to the plan shape of the fillet beach once the western-most headland is constructed. Sand that is normally transported to the east during southwest waves will not be transported back to the west during easterly waves for a shadow zone adjacent to the headland. This will cause the fillet beach to extend in front of Cudia Park to the western headland. That extended beach will be very narrow and perhaps intermittent between the headland and the existing end of the beach. The overall effect on the existing beach will not be noticeable.
Flood Risk in Ecosystem The project will not affect the flood risk in the project area.
Slope Stability Terraprobe (2006) calculated that once the toe is stabilized the lower section of the bluff will obtain a stable slope of 2.5: 1.0 (h:v) and the upper 30 metres will obtain a stable slope of 1.5 : 1 (h:v). Overall the project is considered to have a net positive effect. A buttress proposed at the eastern extent of the project site will stabilize the slope to halt erosion affecting 2 and 10 Meadowcliffe Drive.
Existing Structures/ Hazardous Lands / Hazardous Sites The shoreline protection works will protect the toe of the Meadowcliffe bluff from wave action which will aid in slowing down the rate of erosion thus providing protection of residential structures located on the tableland. However, the shoreline protection is not a sufficient remedial action to protect all of the residential structures along the slope crest. The long-term slope crest of the most eastern section of the project area is predicted to be projected inland by approximately 59 metres on average from the 2005 slope crest once the shoreline protection is in place (Terraprobe, 2009). Over the long-term additional bank stabilization works may be required to prevent the LTSSC from encroaching on the residential dwellings located at 1, 2 and 10 Meadowcliffe Drive.
Hazardous Lands / Hazardous Sites TRCA will continue to administer Ontario Regulation 166/06 to prohibit, regulate or require permission for development within the area of defined erosion hazard as outlined in Figure 14.
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8.0 DESCRIPTION OF ALTERNATIVE CONSTRUCTION ACCESS
Construction of the Meadowcliffe Erosion Control Project will require delivery of considerable volumes of fill, cobble, and armourstone to the project site. To ensure that delivery of construction materials to the project site has the least impact on the environment and the surrounding community TRCA considered all viable options. In all, five possible options were identified.
8.1 Alternative 1 – Bluffers Park Access Route
Trucks delivering materials and equipment to the project site would follow Brimley Road South, into Bluffers Park. Once in Bluffers Park, trucks would follow Bluffers Park Road to the eastern parking lot. The northern most portion of the parking lot would be cordoned off and signed to separate public use areas from the delivery route. A temporary 10 m wide haul road constructed of rubble at an elevation of 2 m above the high water level would be built along the back of the beach.
At the terminus of the beach, an area of shoreline measuring approximately 500 m long would have to be extended lakeward via lakefilling to allow for extention of the haul road eastward to the project site. To ensure worker safety, an operating set back of 20 m from the bluff face is required. The area of lakefill required to accommodate the eastern most section of the haul road is therefore estimated at 17,000 m2.
Figure 21. Alternative 1 – Bluffers Park Access Route. Source: TRCA, 2008.
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8.2 Alternative 2 – Marine Access Route
The Marine Access Route requires the addition of a 200 m groyne to the proposed shore protection design to obtain revised water depths to facilitate offloading of construction materials. Trucks would deliver materials into Bluffers Park via Brimley Road South. Once in Bluffers Park, trucks would offload materials on to barges at the boat launch. A portion of the parking lot would be cordoned off and signed to separate public use areas from the delivery route and offloading area. Loaded barges would then be used to transport materials eastward to the constructed groyne for offloading at the western extent of the project site. Transfer of materials by barge would have to be coordinated with ongoing construction works and in accordance with calm weather conditions to ensure worker safety and prevent loss of materials.
Figure 22. Alternative 2 – Marine Access Route. Source: TRCA, 2008.
8.3 Alternative 3 – Guild Inn Access Route
Trucks delivering materials and equipment to the project site would follow either Galloway Road or Morningside Avenue to the Guild Inn access road located on Guildwood Parkway. Travelling south to the terminus of the Guild Inn access road, trucks would then travel west along TRCA’s shoreline maintenance and service road to the project site. A narrow beach located to the east of Bellamy Ravine would be replaced with a rubble revetment during
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construction of the Meadowcliffe shoreline protection to facilitate access. A temporary access road and crossing would be required at Bellamy Ravine.
Figure 23. Alternative 3 – Guild Inn Access Route. Source: TRCA, 2008.
8.4 Alternative 4 – Bellamy Ravine Access Route
From Kingston Road, trucks would travel south down Bellehaven Crescent and down the Doris McCarthy Trail located in Bellamy Ravine. Upgrades to the trail surface and vegetation clearing would be required to facilitate ongoing truck traffic. Re-grading of the southern extent of the trail may be required to reduce safety risks. A crossing over the drainage swale at the bottom of the ravine would also be required.
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Figure 24. Alternative 4 – Bellamy Ravine Access Route. Source: TRCA, 2008.
8.5 Alternative 5 – Top Dumping
The top dumping alternative would require an access agreement with a private landowner adjacent to the project site to permit the dumping of fill and aggregate materials over the bluff crest to the project below. Truck traffic would travel to Meadowcliffe Drive via Pine Ridge Drive to transport materials to the site.
9.0 EVALUATION OF ALTERNATIVE CONSTRUCTION ACCESS OPTIONS
Each of the five construction access options were evaluated against relevant environmental, cultural and socioeconomic criteria, as outlined below, to determine the negative and positive impacts of each. TRCA’s evaluation of potential impacts focused on the local study area which is defined as the residential neighbourhood located south of Kingston Road.
Technical Considerations • Slope stability • Erosion • Safety
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Natural Environment • Terrestrial habitat • Wildlife • Aquatic habitat • Area of Natural and Scientific Interest ie. geological significance • Unique landforms ie. Bluffs
Socio-Economic Environment • Public recreation • Surrounding residential community • Vistas and scenic views
Feasibility and Cost • Capital and maintenance costs • Impact on other projects • Land requirements
9.1 Alternative 1 – Bluffers Park Access Route
Trucks traveling along Brimley Road South are expected to have minimal impact on surrounding residential community as residences south of Kingston Road are limited to those which back on to the east side of the road. The northern portion of the parking lot adjacent to the East Beach would be closed to separate public use areas from the delivery route. This would address potential safety concerns; however the amount of available parking for beach goers would be reduced during active use of the access road. Noise and dust related to the access road may also impact the beach users’ quality of experience.
A temporary 10 m wide haul road constructed of rubble at an elevation of 2 m above the high water level would be built along the back of the beach. Siting of the haul road would have to confirm that significant flora is protected, as the beach is known to support numerous locally rare species. These species include Beach Pea (Lathyrus japonicus), Sea Rocket (Cakile edentula), Oake’s Evening Primrose (Oenothera oakesiana), Wood Sage (Teucrium canadense), and Wooly Sedge (Carex pellita). A large wetland was also recently constructed by TRCA in 2008 to treat overland runoff and ground water seepage as part of a recent initiative of the Mayor David Miller to improve recreational beaches. Construction of the access road between the beach and wetland may impact drainage of the wetland into Lake Ontario and disrupt associated wildlife use.
At the terminus of the beach, an area of shoreline measuring approximately 500 m long would have to be extended lakeward via lakefilling to allow for extention of the haul road eastward to the project site. To ensure worker safety, an operating set back of 20 m from the bluff face is required. The area of lakefill required to accommodate the eastern most section of the haul road is therefore estimated at 17,000 m2. The access road will take over 85 days to construct at a cost of $250,000. Half the land required to build the road would also have to be acquired from private landowners prior to construction. Furthermore the estimated 25,000 m3 of rubble required to build the road would reduce the amount of available material required to complete the planned shore protection at Meadowcliffe.
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Informal protection of the access road reduces shoreline erosion and thus impacts local sediment sources that contribute to regional transport. Lakefilling adjacent to Cudia Park will stabilize the Bluff, eliminating the unique cliff feature, and affecting Earth Science ANSI (1 of 3 sites selected to represent the geological history of the Bluffs), potentially restricting future scientific study of Pleistocene Geology.
To mitigate the negative impacts associated with the lakefilling adjacent to Cudia Park the area of lakefilled shoreline could be decommissioned following the delivery of the construction materials to the project site. This would however likely double the cost associated with this access route option.
Alternatively the access route could provide a waterfront trail connection between Bluffers Park and Bellamy Ravine; however this option is inconsistent with the recommendations of the Integrated Shoreline Management Plan. TRCA’s current waterfront plan, the Integrated Shoreline Management Plan (ISMP 1996), provides a framework for evaluating and prioritizing site-specific shoreline works, including natural heritage protection and regeneration, lakefilling, private development and public recreation activities. The Plan places emphasis on protecting the few remaining continuously eroding shore cliffs due to their provincial geological significance and contribution to the regional identity. The ISMP states that this section of shoreline should remain in a natural state because it represents one of the few unprotected and natural shores of the Scarborough Bluffs. No major waterfront trail or public access was recommended for this shoreline sector.
As none of the landowners to the west of the project site participated in the Class EA process, lengthy negotiations are likely required to secure the riparian rights of the private lands located between Bluffers Park and Meadowcliffe Drive. Furthermore, while several members of the public noted interest in a waterfront trail connection between Bluffers Park and Bellamy Ravine, this was not the primary focus of this EA. As part of TRCA’s long-term waterfront planning, staff will continue to engage the public in discussions regarding a potential trail connection to discuss the merits of this option.
9.2 Alternative 2 – Marine Access Route
The Marine Access Route requires construction of a 200 m groyne to facilitate offloading of materials from barges at the western terminus of the project site. The groyne is valued at approximately $1,000,000 and would take an estimated 40 days to construct. Additional costs to the project are associated with additional delivery costs and restrictions on timing of delivery that are incurred by using marine equipment.
In addition to the considerable increase in project costs, other negative impacts associated with this access route include disruption of the eastward movement of sediment which would result from construction of the groyne and influence on deposition adjacent to Cudia Park. This increase in deposition is expected to eliminate the unique cliff feature, which will impact the aesthetic nature of the shoreline and restrict future scientific study of Pleistocene Geology.
Delivery of construction materials by barge would significantly reduce local construction traffic to and from the immediate project site; however barges would be loaded at Bluffers Park which is located within the local community. Once in Bluffers Park, trucks would be offloaded to barges at the boat launch. During this operation both the boat launch and parking lot would be
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closed for public use. As the use of marine equipment requires warm, calm weather, closure of the boat launch and adjacent parking area would likely coincide with the boating season. The potential for negative impacts on recreational boating and park use is therefore considerable. Furthermore, the boat basin may require dredging to provide required depths for marine equipment.
9.3 Alternative 3 – Guild Inn Access Route
The Guild Inn service road is located about 3.5 km east of the existing project site. To construct a connection from the terminus of the existing shoreline access road to the Meadowcliffe project site would take approximately 25 days at an estimated cost of $35,000. Upon completion of the project restoration of the former beach would be required. The cost to remove the rubble revetment and reinstate the sand/gravel beach is estimated at upwards of $100,000. Extra material handling costs may also be incurred as a result of utilizing this access route due to the distance trucks are required to travel along the shoreline service road from Guild Inn. Truck traffic along the access route will restrict recreational use and may temporarily displace wildlife when in use. The most significant impact related to utilizing this access route is the disturbance to the residential community adjacent to the Guild Inn service road entrance.
9.4 Alternative 4 – Bellamy Ravine Access Route
Use of the Doris McCarthy Trail located in Bellamy Ravine will require surface upgrades and widening to accommodate truck traffic. TRCA recognizes the presence of provincially and regionally uncommon plant species within Bellamy Ravine which may be impacted during construction of the access road. Bellamy Ravine also provides refuge for songbirds during the spring and fall migration. Truck traffic and clearing of vegetation is expected to have some short-term impact on these birds and other wildlife which reside in the ravine.
Other considerations related to the use of this access route include worker safety as the road would only be able to accommodate one lane of truck traffic. Truck movements would therefore have to be controlled at the north and south entrance to prevent accidents. This may cause traffic concerns along Kingston Road and Bellehaven Crescent as trucks may have to enter queue before entering the access route.
Increased truck traffic, queuing vehicles and location of trucks in relation to neighbouring private properties adjacent to the ravine have potential for considerable impact to the local community. Property easements may also be required at top of ravine to facilitate truck access.
Review of this option by TRCA engineering staff also determined that the steep nature of the slope at the bottom of the ravine and potential for slope failures may place limitations on the use of the existing trail for construction access during wet weather or winter conditions. A subsequent study completed by Terraprobe in 2009 (see Appendix D) confirmed that lower slope conditions in Bellamy Ravine are not sufficiently stable and safe to permit access by heavy construction vehicles.
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9.5 Alternative 5 – Top Dumping
In the interest of exploring all available options TRCA reviewed the potential to utilize a top dumping method to deliver construction materials to the site. This method has not been utilized by TRCA in recent years due to the significant safety risk to staff, related to operating equipment at the top of the unstable bluffs. The height and instability of the bluffs create potential for sudden slope failures which places workers at undue risk. Slope failures will also likely result in some of the delivered materials being buried, increasing cost related to recovery or replacement of the affected material.
It is also expected that erosion generated by materials being dumped over the edge of the bluffs would result in ongoing release of sediment into lake. Turbidity resulting from this release of sediment is expected to have negative affects on fish and fish habitat.
Other impacts related to this option include disturbance to local residents caused by truck traffic and noise of dumping of materials.
10.0 PREFERRED ACCESS ROUTE
The evaluation results as presented in Section 9.0 identified that the access route with the least negative impacts is to utilize TRCA’s existing service road which provides shoreline access from the Guild Inn. Impacts associated with this option largely relate to the distance trucks would be required to travel at a low rate of speed along the shoreline and the cumulative impact of increased truck traffic in the surrounding residential community. These impacts however are temporary in nature. TRCA has worked with the community to address public concerns related to this option to ensure that all potential impacts are mitigated.
10.1 Public Comments on Preferred Construction Access Route
The primary concerns raised by the public about the proposed construction access route via the Guild Inn service road were the following:
• Public accessibility to the shoreline during the periods of construction. • Pedestrian and vehicle safety with the increase truck traffic through the Guildwood community. • Disturbance to existing wildlife and vegetation along the shoreline and Scarborough bluffs. • The noise of the construction activity through the Guildwood community and along TRCA service road. • The effects of the vibration from the construction activity on the stability of the bluffs. • The creation of dust from the construction activity.
TRCA has taken measures to address each of the concerns raised to either minimize or mitigate any negative impacts potentially associated with the use of the proposed access route.
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A copy of TRCA letter to the GVCA and the newsletter to the public that outlines the mitigative measures proposed by TRCA to address issues raised during the public consultation process are included as Appendix C.
10.1.1 Public Accessibility
TRCA is aware that many members of the Guildwood community utilize the Guild Inn service road to gain access to the shoreline. However, as the primary purpose of the service road is to provide TRCA with vehicle and equipment access to the shoreline, TRCA must restrict public access during periods of active operation in order to ensure public safety. While the service road was not intended as a formal pedestrian trail, TRCA understands the importance of maintaining this informal public use. As such TRCA is committed to allowing the public access to the service road for recreational purposes on public holidays, weekday evenings (between 5:00 pm and 7:30 am) and weekends (from 4:30 pm on Friday to 7:30 am on Monday). TRCA will also endeavour to minimize disruption to public use of the service road during warm weather months from April to October. Moreover, TRCA will commit to provide the public with formal notification of construction or maintenance activities to improve communication with the community.
10.1.2 Guildwood Community Public Safety
The review of the comment forms revealed the Guildwood communities major concern was public safety with the potential impact of increased truck traffic throughout the community during the construction of the Meadowcliffe Drive Erosion Control Project. Since the public meeting held to discuss the proposed access route, TRCA has completed a road traffic impact study through the Guildwood Village to assess the potential risk to public safety. As part of this study TRCA retained transportation planning firm iTrans to collect baseline information on traffic volume and patterns along the proposed route and assess the type and degrees of impacts resulting from the delivery of material via the Guild Inn service road.
The study was completed in two phases to be able to collect representative data during different periods of traffic conditions (i.e. summer vs. post-summer). All the pedestrian and vehicle data was collected at the intersections of Guildwood Parkway/ Livingston Road, Navarre Crescent/TRCA construction driveway, and Guildwood Parkway/Galloway Road. For Phase I of the study, the data was collected over a 2 week period in July 2009 during inactive and active use of the Guild Inn service road for comparison purposes. Phase II of the study was completed over a week period at the end of September 2009 to capture additional data when school is in session and to reflect local residents return from summer holidays.
The results of the Phase I (summer conditions) indicate that TRCA truck traffic represents about 0.8 % of the peak hour (1:30 pm to 2: 30 pm) traffic and 1.0 % of the eight hour (7:30 am to 3:30 pm) traffic, which is not a conspicuous number in terms of traffic volumes. During Phase II (post-summer conditions) the results indicate that there was a minimal increase of TRCA truck traffic which represents 0.9% of the peak hour (8:30 am to 9:30 am).
The peak hours during the summer and post-summer conditions were observed at different periods of the day. The peak hour of the summer conditions was from 1:30 pm to 2:30 pm inferred to be the local community members commuting to the local market and the peak hour
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of post-summer conditions was from 8:30 am to 9:30 am inferred to be members of the community commuting to and from work/school.
In general, the pedestrian traffic along Guildwood Parkway was significantly higher during the summer conditions compared to the post-summer conditions with a magnitude of 201 pedestrians versus 97 pedestrians. During these periods the truck traffic slightly increases from 3 TRCA trucks during the peak hour of the summer conditions to 4 TRCA trucks during the peak hour of the post-summer conditions.
This study has concluded that TRCA truck traffic increases the local Guildwood Village traffic by 0 to 2%, which is not foreseen as a public safety concern to pedestrians. A copy of the Traffic Impact Study completed by iTrans Consulting Inc. is contained in Appendix D.
TRCA will use the results of the traffic impact study in the development of an operation plan that will seek to effectively avoid, minimize or mitigate any potential negative impacts associated with the continued use of the Guild Inn service road. TRCA proposes that the operation plan will prescribe the following:
• All trucks contracted by TRCA to transport materials to the Meadowcliffe project site will be provided a map with clearly identified inbound and outbound routes, operation hours and safety protocols. • Trucks will be directed by TRCA to utilize Morningside Avenue as the inbound route to the Guild Inn service road entrance located on Guildwood Parkway. • Trucks will be directed by TRCA to exit the Guild Inn service road westbound on Guildwood Parkway to Kingston Road.
Based on the current level of funding for this project, construction activity will be intermittent over the next five years. Working with members of the CLC and representatives from the GCVA executive, TRCA will ensure that the operation plan outlines a material delivery schedule that considers the availability of funding and the need to minimize disruption to the surrounding community. TRCA will also work with the CLC and GVCA to maintain regular communication with the community regarding the progress of construction.
10.1.3 Disturbance to Existing Vegetation and Wildlife
TRCA is committed to minimize the disturbance to the vegetation and wildlife. A review of the proposed access route has determined that no vegetation will be impacted by utilizing the existing Guild Inn and shoreline service roads. At the transition area between the project site and Bellamy Ravine a grassy area, composed of early successional plant species will be cleared to accommodate the access road. This area will be restored at a 3:1 ratio with a native seed mix, as such the impact on existing vegetation is considered minimal and temporary in nature. TRCA does however recognize that use of the shoreline service road may temporarily disrupt wildlife use. This impact is related to truck noise and will be limited to active use periods which are expected to be intermittent over the course of the construction period and temporary in nature.
10.1.4 Noise
To diminish the potential for noise from construction activity, all construction trucks will meet
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manufacturer sound attenuation specifications; and the project site will be in compliance with time prohibitions for delivery of materials and operation of construction equipment per the Toronto Municipal Code, Chapter 591 and other applicable noise protocols.
10.1.5 Vibration
TRCA contacted an engineering firm with professional experience in vibration monitoring, Terraprobe Limited, to comment on the effects of vibration on the stability of the bluffs in relation to the proposed construction route. The firm stated that the vibration from the construction would not have any significantly adverse impact on the stability of the Scarborough Bluffs. At any time during construction if there is any question of the stability of the bluffs due to the vibration generated by construction activity TRCA will respect the need for an engineering firm to complete vibration monitoring.
A copy of the letter on vibration impact commented by Terraprobe Limited is contained in Appendix D.
10.1.6 Dust
In order to minimize the amount of dust generated by construction, mud build up on the roads surrounding the site will be removed by street sweepers when required and trucks transporting earth fill to the site will be covered with a tarpaulin. Efforts will be taken to transport construction materials to the site and stockpile them to avoid having to use the access roads during dry summer months when dust problems are exacerbated. Dust polymers approved by the Ministry of the Environment will be applied along TRCA’s service access road to minimize dust generated by trucks during dry weather conditions. Furthermore, truck drivers will also be reminded by the on-site construction supervisor of the City of Toronto’s anti-idling bylaw. By taking these precautionary measures TRCA believes that the public’s concerns related to dust can be addressed.
11.0 SUMMARY OF PUBLIC CONSULTATION
This section of the Environmental Study Report provides a summary of comments received during the planning and design phases of the project, and a discussion of how these concerns have been addressed.
11.1 Role of the Community Liaison Committee
The following information is provided from Conservation Ontario’s Class Environmental Assessment for Remedial Flood and Erosion Control Projects (January 2002).
“In an effort to facilitate more on-going public involvement at the project level, the Conservation Authority shall, based on its contact group mailing lists and expressions of interest from the local landowners, members of the general public, interest groups, or agencies, establish a Community Liaison Committee (CLC) to assist the Authority by obtaining additional public input concerning the planning and design process of an individual flood and/or erosion control project, and to review
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information and provide input to the Conservation Authority throughout the process. The Conservation Authority shall strive to ensure that the membership of the CLC is representative of all views respecting a proposed remedial and erosion control project. (Conservation Ontario, 2002).”
“As the name implies, the function of the CLC, in the Class EA process, will be to assist the Conservation Authority to reach out and maintain contact with community residents, groups, associations and organizations. The CLC will provide direct input into the process. At the end of the process, the entire committee will have been exposed to the entire process, will have understood how decisions have been reached and will have had their questions answered during the process.
To fulfill its function, the CLC will:
• Identify items of public concern with regard to the impact and design of proposed erosion control alternatives;
• Provide direct input on these concerns to the Conservation Authority to be utilized throughout the planning and design process;
• Co-host, with Authority Staff, meetings organized by the Authority to facilitate the resolution of concerns relating to a proposed remedial work;
• Review any Part II Order Requests made by members of the public and attempt to resolve the issues of concern between the Part II Order requesters and the Conservation Authority before the request gets referred to the Minister of the Environment for a decision; and
• Where appropriate, submit an assessment to the Conservation Authority, upon project completion, commenting on the effectiveness of the Class EA process for meeting public concerns for the specific project, and where relevant, identify possible improvements (pp.36- 37) (Conservation Ontario, 2002).”
More information regarding the CLC is described in the following section.
11.2 Public Notifications and Consultation The following is a summary of all public notifications and the consultation process completed in support of the Meadowcliffe Drive Erosion Control Project. Documents related to public outreach component of this project; including all published notices, meeting materials and minutes, and comment forms are included in Appendix C.
Comment forms were distributed by TRCA following each public consultation session to ensure that an understanding of the project objectives and direction was maintained throughout the planning process. The forms also provided a means of soliciting input into the planning and
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design phases of the project, and were utilized in the development of the alternative options considered and in the selection and refinement of the preferred alternative. Written comments ensured that ideas and concerns were investigated and addressed at meetings, facilitating open dialogue between staff and the general public.
11.2.1 Notice of Intent
In accordance with the Class EA process, the first point of public contact occurred when the Notice of Intent was published in the Scarborough Mirror on September 15, 2006. The Notice of Intent was also delivered to the following:
• TRCA staff with an interest in the project • City of Toronto staff with an interest in the project • Conservation Ontario • Councillor Brian Ashton, Ward 36 – Scarborough Southwest • Lorenzo Berardinetti, M.P.P., Scarborough Southwest • Ministry of the Environment • Ontario Heritage Trust
A Community Liaison Committee (CLC) was subsequently formed, which included the affected landowners, TRCA staff and other individuals who expressed an interest in the project.
11.2.2 Community Liaison Committee Meeting #1
The first CLC meeting, held on October 11, 2006 at 1 Eastville Avenue, was attended by several staff from TRCA, Councillor Brian Ashton, several local property owners, an employee from Toronto Water, staff from Shoreplan Engineering Ltd., and staff from Terraprobe Limited.
Four alternative techniques utilized in shoreline stabilization project with similar conditions to those found along the shoreline below Meadowcliffe Drive were presented to the attendees. The four techniques presented were:
1. Segmented Breakwater Beach 2. Revetment 3. Headland/Groyne Beach 4. Boulder Berm
Additionally, the “Do Nothing” option was discussed. Examining this option is a required step of the Class EA process, and is used as a tool to demonstrate the results of not undertaking remedial works. Through the examination of the Do Nothing option it was illustrated that the long-term, stable slope crest for this unprotected section of the shoreline would place numerous homes, the road, and other public infrastructure at risk.
At the conclusion of the meeting, a comment form was distributed to the participants asking for input into the next steps of the planning process for the project.
Based on the comment sheets received there was a strong preference for a Headland beach system. Reasons cited for the preference include:
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• Provides an attractive, diverse habitat for plants and wildlife. • Similar structure east of Bellamy Ravine appears to be quite effective at stopping toe erosion. • It would be aesthetically pleasing. • Potential to improve terrestrial and fish habitat in long-term.
The documentation of this meeting is contained in Appendix C.
11.2.3 Community Liaison Committee Meeting #2
CLC meeting #2 was held on February 7, 2007 at 1 Eastville Avenue, and was attended by several staff from TRCA, staff from Shoreplan Engineering Ltd., Councillor Brian Ashton, several local property owners, representatives for Lorenzo Berardinetti, M.P.P., a representative from the Ontario Heritage Trust, and a City of Toronto staff member.
Shoreplan Engineering Ltd. (Shoreplan) presented nine alternative design concepts, and provided rough cost estimates for each of the proposed options. A comment form was distributed to the CLC to provide feedback on each of the options presented, to select the preferred design concept, and to assess the importance of the evaluation criteria for each of the concepts presented.
It was communicated to the CLC members that the rating of the criteria would have an impact on the overall evaluation of the preferred option. Further it was explained that the rating of each individual criterion may not be held on par, based on project specific constraints. The evaluation is based on the screening criteria mandated in the Class EA document (Conservation Ontario, 2002).
In order to assess the relative importance of the evaluation criteria, CLC members were asked to rank each criterion on a scale of 1 to 5, 5 being the most important, 1 being the least important, NC being “no comment”. The results of the rankings from the five (5) returned comment sheets are documented in Section 5.2.
As illustrated in Table 13 and Figure 19 the technical and engineering (e.g., rate of erosion, sediment deposition, flood risk and slope stability) and physical (e.g., unique landforms, air quality, existing transportation routes, noise and vibrations) criteria were considered to be of greatest importance by the CLC members.
The results of the returned ranking forms also indicate that the preferred design concept selected by the CLC members was the Headland Beach Concept (1a), which provides protection to Meadowcliffe Drive only. Comments included on the forms included:
• Headland Beach – Meadowcliffe Drive (Concept 1a) is the only concept considered to be the most practical in terms of cost, property protection, and beach access for the public. • Headland Beach – full site (Concept 1b) is effective but costly. The member has reservations about implementing shoreline protection for the entire project limits since the majority of the erosion is concentrated at the Meadowcliffe Drive shoreline.
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• Groyne Retained Sand Beach – Pre-fill Beach (Concept 4c) is too expensive. • The shoreline from Bluffers Park to Port Union should be connected in order to facilitate pedestrian recreational use and future TRCA shoreline protection construction or maintenance.
The preferred alternative will include the following features:
• A cobble beach retained by 4 headlands. • The end headlands will be constructed like “L” groynes, with armour stone along the outside of the headlands. • The western-most headland has a small spur on its west side to help retain any sand transported alongshore from the Bluffer’s Park beach. • The two central headlands will be constructed from shore but only the shore-parallel component of those headlands will be armoured. • A buttress of earth, rock or rubble fill from the toe of slope to elevation 84 m, with an inclination of 2.5:1 (H:V)
The documentation of this CLC meeting is contained in Appendix C.
11.2.4 Public Meeting #1
A public open house was held on May 9th, 2007 at the Scarborough Village Recreation Centre. The purpose of the public open house was to invite the general public to view the preferred alternative. The open house was advertised in the Scarborough Mirror on May 2nd, 2007 and separate invitations were sent to each of the CLC members. There were approximately twenty- seven (27) individuals in attendance at the open house.
The meeting consisted of an open discussion period with display boards illustrating the details of the existing conditions and the preferred alternative, followed by a presentation by TRCA staff, and Shoreplan Engineering that discussed the Class EA process, and provided the attendees with the process and rationale used in the selection of the preferred alternative. A comment form was distributed at the meeting asking attendees to provide their comments and general thoughts on the preferred alternative. Five (5) completed comment sheets were submitted, and 100% of respondents understood and agreed with the preferred alternative.
The documentation of this public open house is contained in Appendix C.
11.2.5 Public Meeting #2
A public information session was held at Sir Wilfred Laurier Collegiate Institute on January 14, 2009 to discuss past and present shoreline stabilization projects along the Lake Ontario waterfront including Guildwood Parkway, Guild Inn and Meadowcliffe Drive.
The information session was advertised in the Scarborough Mirror on January 7th, 2009 and on the Guildwood Village Community Association (GVCA) website. Furthermore, newsletters and invitations were delivered to 600 area residents, GVCA, Ontario Heritage Trust, City of Toronto, Shoreplan Engineering Limited, Councillor Brian Ashton, Councillor Paul Ainslie, and provincial and federal government officials. There were approximately fifty (50) individuals in attendance
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at this meeting.
The meeting consisted of an open discussion and display board period followed by a presentation by TRCA staff discussing the Meadowcliffe Drive Class EA. As part of the presentation, a detailed analysis of the five main construction access options considered was provided. Each route was thoroughly evaluated and discussed in relation to the natural environment, technical consideration, socio-economic impacts, feasibility and cost.
The proposed preferred construction access route is through the Guildwood community, accessing the shoreline by way of Guild Inn and traveling along the service road to the Meadowcliffe sector. This service road has been owned and operated by TRCA for more than 25 years for vehicle and equipment access to TRCA’s shoreline erosion control project sites. A comment form was distributed at the meeting asking attendees to provide their comments and general thoughts on the preferred alternative, and on the proposed construction access route. Twenty-three (23) completed comment forms were submitted to TRCA after the meeting. The primary concerns identified in the comment forms and at the meeting were those pertaining to the proposed construction access route via the Guildwood Community to access the Meadowcliffe shoreline sector.
A hybrid construction access route was discussed during the session and many favourable comments on this route were noted on the comment forms. Since the information session, TRCA retained a geotechnical engineering firm to conduct a feasibility study to develop the hybrid construction access route. The construction trucks would enter from the Guild Inn travel along the shoreline service road to the project site and exit via Bellamy Ravine. The results of the study concluded the lower slope conditions in Bellamy Ravine were not sufficiently stable and safe to permit access by heavy construction vehicles. Based on these results the hybrid option was eliminated as an alternative for construction access. A copy of the Bellamy Ravine Slope Stability report completed by Terraprobe Limited is contained in Appendix D.
TRCA received a letter from the GVCA raising their concerns related to TRCA’s preferred construction access related to increased truck traffic through the Guildwood community. TRCA also received a letter from the Ontario Heritage Trust, the property owners of 1 Meadowcliffe Drive. The Trust strongly supports the Guild Inn construction access route and objects to the use of the Doris McCarthy Trail as an access option (also known as Alternative 4 - Bellamy Ravine Access Route). The concerns noted on public comment forms about the proposed construction access route through the Guildwood Community were similar to the concerns raised by the GVCA. These concerns can be summarized as follows:
• Public accessibility to the shoreline during the periods of construction. • Pedestrian and vehicle safety with the increase truck traffic through the Guildwood community. • Disturbance of existing wildlife and vegetation along the shoreline and Scarborough bluffs. • The noise of the construction activity through the Guildwood community and along TRCA service road. • The effects of the vibration from the construction activity on the stability of the bluffs. • The creation of dust from the construction activity.
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11.2.6 Meetings with the Guildwood Village Community Association
TRCA held meetings with representatives of the GVCA and the local councillors on several occasions to address the concerns associated with TRCA’s preferred construction access route. TRCA has developed and presented measures to address each of the concerns raised to either minimize or mitigate any negative impacts potentially associated with the use of the proposed access route as outlined in Section 10.
11.2.7 Notice of Filing
The second public notification will occur when the Environmental Study Report is filed on March 4, 2010. As per the requirements of Section 4.2 of the Class EA document, a Notice of Filing shall be published in the same newspaper as the Notice of Intent, in this case the March 4, 2010 issue of the Scarborough Mirror, and shall be sent to all parties contacted in the first notification process who expressed an interest in the remedial work and to Conservation Ontario and the Ministry of the Environment. Copies of this report will be provided at the Cliffcrest Public Library, Guildwood Library, TRCA’s website, and at TRCA’s Eastville office for public review during the 30 day review period.
11.2.8 Notice of Project Approval
In the interest of good project management, a Notice of Project Approval and a Notice of Project Completion shall be sent to all parties who expressed an interest in the project and to Conservation Ontario.
12.0 MONITORING PROGRAM
Given the nature of coastal interventions over the past 50 years across North America, TRCA anticipates that an adaptive management approach will be necessary, to allow modifications to the overall design based on continued monitoring, evaluation of shoreline processes, slope stability, International Joint Commission changes to Lake Ontario water level regulations and long-term effects of climate change.
A program monitoring the performance of the shoreline protection works and beach is proposed, and will consist of frequent visual inspection and formal surveys, with comparisons being made to expected performance. Immediately following construction, the visual inspection will be completed after each storm event. Surveys will be conducted annually until a period of five years has passed, after which time inspection will be reduced to an appropriate frequency.
If a significant deviation from expected performance is noted during a visual inspection, additional surveys will be undertaken immediately. If a survey detects a significant deviation from expected performance, then remediation construction will be planned and implemented immediately such that the shore connected headlands and the cobble beach sections meet design performance criteria at all times.
The armour on the headlands will be inspected noting any significant displacement or slumping of the armour. The armour layers will be placed, in the original construction, in a specific placement such that the sub-armour layers cannot move through the main armour. Any
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displacement of the armour layer that exposes the sub-armour will be noted and repaired. Slumping of the armour layer may indicate that the toe protection has moved or has been undercut. If slumping is noted, the toe protection will be inspected, and surveyed to detect any undercutting.
Some overtopping of the headland sections is expected. Inspections will include looking for dislodged armour on top and on the inshore side of the headlands, and eroded material inshore of the revetment. Suitable remedial construction will be planned and completed immediately such that the headlands and revetments maintain design integrity.
Offshore profiles of the lake bottom will be recorded to detect any downcutting of the foreshore, and /or any undercutting of the toe protection of the headlands and revetment sections. Surveys will be undertaken once every 3 to 5 years as required.
Ongoing monitoring of the slope crest will also be required to confirm slope recession rates and the projected LTSSC. This data will confirm the need and timing of future works which may include construction of a slope buttress to reduce the severity of ongoing slope recession.
13.0 REFERENCES
Atria, 1993. Beach Stabilization Alternatives Tank II, Eastern Beaches. Report prepared for Gore & Storiie Limited. (cited in Reinders et al, 1994)
Baird, 1994. Sylvan Ave Shoreline Management Project Coastal Processes Report. Unpublished report prepared for F.J. Reinders and Associates and The Metropolitan Toronto and Region Conservation Authority by Baird & Associates. Final report. 18 April 1994.
Canadian Council of Ministers of the Environment (CCME) website. 1999. Canadian Environmental Quality Guidelines. (www.ec.gc.ca).
City of Toronto website. 2001 and 2006. Cliffcrest Neighbourhood Profile. (www.toronto.ca/ demographics /cns _ profiles/cns123.htm).
Conservation Ontario. 1993 & 2002. Class Environmental Assessment for Remedial Flood and Erosion Control Projects.
Fisheries and Oceans Canada (DFO) website. 2009. Species at Risk. (www.dfo-mpo.gc.ca)
Fisheries and Oceans Canada (DFO) website. 2009. Monthly Water Level Bulletin. (www.waterlevels.gc.ca).
Eakins, R. J. 2009. Ontario Freshwater Fishes Life History Database. Version 2.98. On- line database. (www.fishdb.ca).
Eden, David J. and Eyles Nicholar. 2002. Case Study of a Relict Iceberg Scour Exposed at Scarborough Bluffs, Toronto, Ontario: Implications for Pipeline Engineering. Canadian Geotech. J. 39: 519-534.
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Environment Canada, Ministry of the Environment, Ministry of Natural Resources, Toronto and Region Conservation Authority.1989. Metro Toronto and Region Remedial Action Plan. Stage 1. Environmental Conditions and Problem Definition.
Environment Canada, Canadian Wildlife Service, Blokpoel, H. and Tessier, G.D. 1991. Distribution and Abundance of Colonial Waterbirds Nesting in the Canadian Portions of the Lower Great Lakes System in 1990, Technical Report Series No. 117.
Environment Canada website. 2009. Water Quality. (www.ec.gc.ca).
Geocon Inc. 1982. Erosion Control Study, Stage 2, Scarborough Bluffs.
Geocon Inc. 1996. Slope Stability Study, Meadowcliffe Drive.
Golder Associates Ltd. 1990. Subsurface Investigation, Meadowcliffe Drive Sewer Works and Storm Sewer Outfall to Bellamy Ravine.
Google Earth. 2005. Map of Project Area.
Great Lakes Information Network (GLIN) website. 2009. Invasive Species in the Great Lakes Region. (www.great-lakes.net/).
Guildwood Village Community Association (GVCA) website. 2009. (www.guildwood.on.ca). MapArt Corporation. 2005. Toronto and Area. Oshawa, Ontario: Peter Heiler Ltd.
Metropolitan Toronto Planning Department, Research and Special Studies Department Division. 1995. State of the Environment Report: Metropolitan Toronto.
Ministry of the Environment.1985. Historical Development and Quality of the Toronto Waterfront Sediments - Part I.
Ministry of the Environment (MOE). 1993. Water Resources. Guidelines for the Protection and Management of Aquatic Sediment Quality in Ontario.
Ministry of the Environment (MOE) website. 1994 (Reprinted 1999). Provincial Water Quality Objectives. Water Management. (http://www.ene.gov.on.ca).
Ministry of the Environment (MOE). 2009. Local Air Quality. (www.ene.gov.on.ca).
Ministry of Natural Resources (MNR). 1974. Operation Doorstop Angling: Metropolitan Toronto Fishery Project Report - Volume One.
Ministry of Natural Resources (MNR). 1984. Life Science Areas of Natural and Scientific Interest in Site District 7-4: A Review and Assessment of Significant Natural Areas in Site District 7-4.
Ministry of Natural Resources (MNR). 1989. Fish Community and Aquatic Habitat of the Toronto Waterfront.
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Ministry of Natural Resources (MNR). 1989. Great Lakes Flood Levels and Water Related Hazards, prepared by Conservation Authorities and Water Management Branch, Ontario Ministry of Natural Resources, February, 1989
Ministry of Natural Resources. 1994. 1989 - 1993 Toronto Waterfront Fish Communities: Summary and Assessment.
Ministry of Natural Resources (MNR). 1998. Earth Science Database.
Ontario Heritage Trust website. 200. Provincial Plaque Unveiling Commemorates Fool’s Paradise – Home and Studio of Renowned Artist Doris McCarthy. (www.heritagefdn.on.ca/ userfiles/ HTML/nts_1_8214_1.html).
Reinders, Baird and BAR. 1994. Sylvan Avenue Shoreline Management Plan, Scarborough, Ontario. Unpublished report prepared for The Metropolitan Toronto and Region Conservation Authority by F.J. Reinders and Associates Canada Ltd. with W.F. Baird and Associates and B.A.R. Environmental.
Roots, B., Chant, D.A. and Heidenreich, C.1999. Special Places: The Changing Ecosystems of the Toronto Region.
Royal Commission. 1990. Royal Commission on the Future of the Toronto Waterfront.
Shoreline Management Work Group for the Waterfront Regeneration Trust. 1996. Shore Management Opportunities for the Lake Ontario Greenway.
Shoreplan Engineering, 2010. Meadowcliffe Drive Coastal Analysis and Final Report, Toronto.
Terraprobe Ltd. 2001. Geotechnical Investigation and Slope Stability Assessment, Meadowclife Drive.
Terraprobe Ltd. 2006. Geotechnical Review of Slope Stability and Erosion, Meadowclife Drive, Scarborough Bluffs, Toronto.
Terraprobe Ltd. 2009. Geotechnical Review of Slope Stability and Erosion Stabilization Options, Meadowclife Drive, Scarborough Bluffs, Toronto.
Toronto and Region Conservation Authority (TRCA). 1978-1987. Grain Size and Sediment Quality of the Toronto Waterfront Areas from 1978 to 1987.
Toronto and Region Conservation Authority (TRCA). 1979. Review of the Waterfront Environmental Monitoring Program. Proctor and Redfern Limited.
Toronto and Region Conservation Authority (TRCA). 1982. Environmentally Significant Areas Study.
Toronto and Region Conservation Authority (TRCA). 1994. Sylvan Ave. Erosion Control Project. Terrestrial and Aquatic Resource Inventory Report.
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Toronto and Region Conservation Authority (TRCA). 1996. Integrated Shoreline Management Plan: Tommy Thompson Park to Frenchman’s.
Toronto and Region Conservation Authority (TRCA). 2000. Toronto Waterfront Fisheries Communities.
Toronto and Region Conservation Authority (TRCA). 2004. Environmental Study Report. The Guild Inn Shoreline Regeneration Project City of Toronto.
Toronto and Region Conservation Authority (TRCA). 2004. Toronto Waterfront Aquatic Habitat Restoration Strategy.
Toronto and Region Conservation Authority (TRCA). 2006. Watershed Management Advisory Board Meeting #2/06, June 16, 2006.
Toronto and Region Conservation Authority (TRCA) website. 2009. Significant Landforms; Oak Ridges Moraine. (www.trca.on.ca).
Toronto Neighbourhoods website. 2009. Cliffcrest. (www.torontoneighbourhoods.net/regions/ scarborough).
Toronto Ornithological Club. 2002. Species of Shoreline. Recorded Between Jan 1, 1930 and August 18, 2002.
Toronto Transit Commission (TTC) website. 2009. Bus Routes, 86 Scarborough. (www.ttc.on.ca).
Waterfront Regeneration Trust. 1987. Toronto Eastern Waterfront Summary: A Report for the Toronto Remedial Action Plan Work Team. Beak Consultants Ltd.
Waterfront Regeneration Trust. 1995. Lake Ontario Greenway Strategy. Waterfront Regeneration Trust. 1995. Lake Ontario Greenway Strategy, Next Steps.
Waterfront Regeneration Trust. 1995. Lake Ontario Waterfront Experiences.
Waterfront Regeneration Trust. 1995. The Waterfront Trail.
Waterfront Regeneration Trust. 2002. Clean Waters, Healthy Habitats: Progress Report 2001 Technical Edition - Toronto and Region Remedial Action Plan.
Winter Burnside. 2002. Meadowcliffe Drive Area Storm Drainage Study for City of Toronto.
95 Environmental Study Report Toronto and Region Conservation Authority Meadowcliffe Drive Erosion Control Project March 2010