Section 7.0 of the Management Plan Technical Report document provides a detailed description and ...... Regulating activ
T A B L E O F C O N T E N T S 1.1
Background
1
1.2
Structure of the Management Plan
1
1.3
Purpose of the Management Plan
3
1.4
Goal and Objectives
4
1.5
Management Plan Development Process
5
1.6
Public Consultation
6
1.7
Site Inventory and Analysis
7
1.7.1 Vegetation Communities
8
1.7.2 Invasive Species
9
1.7.3 Management of Tree Health
9
1.7.4 Drainage Features Seepage
1.8
10
1.7.5 Drainage Features – Ames Creek
11
1.7.6 Steep Slopes
11
1.7.7 Soil Erosion
12
1.7.8 Structures – Timber Retaining Walls
13
1.7.9 Structures – Stairs and Boardwalks
13
1.7.10 Access and Use
14
1.7.11 Interpretation
15
Management Options
15
1.8.1 Management Option ‘A’
17
1.8.2 Management Option ‘B’
19
1.8.3 Preferred Option
22
Schollen & Company Inc. Landscape Architects ~ NorthSouth Environmental Inc ~ Pterophylla dmA Planning & Management Services ~ Arborvitae Environmental Services Ltd. ~ Unterman McPhail Associates
1.9
Glen Stewart Management Plan
22
1.9.1 Trail Management Plan
23
1.9.2 Ecological Management Plan
23
1.10
Management Prescriptions
27
1.11
Implementation Priorities
27
1.11.1 Management Prescription Priority Tables
28
1.11.2 Immediate Priorities, 02 years
29
1.11.3 Short Term Priorities Safety, 26 years
31
1.11.4 Short Term Priorities – Slope Stability, 26 years 33
1.12
1.13
1.11.5 Medium Term Priorities, 510 years
35
1.11.6 Long Term Priorities, 1020 years
37
Maintenance and Monitoring
39
1.12.1 LongTerm Maintenance Initiatives
39
1.12.2 Monitoring Initiatives
41
1.12.3 Tracking and Reporting
42
Roles and Responsibilities
43
1.13.1 City of Toronto
43
1.13.2 TRCA
44
1.13.3 Community/ Volunteer Involvement
45
1.14
Funding Opportunities
46
1.15
Conclusion
47
Schollen & Company Inc. Landscape Architects ~ NorthSouth Environmental Inc ~ Pterophylla dmA Planning & Management Services ~ Arborvitae Environmental Services Ltd. ~ Unterman McPhail Associates
1..1
Glen Stewart Ravine Management Plan
OCTOBER 2008
Ba ackgro oun nd
Glen Stewart Ravine is located within the Beach community in the City of Toronto. The ravine was designated in 1981 under the City of Toronto’s Ravine Protection Act. The study area encompasses 8.5 ha of ravine landscape and is bounded on three sides by single family dwellings. The ravine is wholly owned by the City of Toronto and regulated by the City and the Toronto and Region Conservation Authority (TRCA). Glen Stewart Ravine has been designated as an Environmentally Significant Area (ESA) by the TRCA. It is also a component of the City’s Natural Heritage System incorporating important ecological, hydrological and geological functions. The Toronto Ravine ByLaw promotes the environmentally responsible management, protection and conservation of ravines and associated woodlands. The protection of the ravine is important to safeguard public and private property, to maintain the integrity of the forest and rare species of flora and fauna and their habitats. Glen Stewart Ravine contains drainage features that are important within the watershed to ensure that water quality and fish habitat are protected downstream of the site. The vegetated slopes of the ravine offer habitat for birds and wildlife and enhance slope stabilization. As well, a healthy and intact ravine system provides aesthetic, visual, and recreational amenities to the Beach community. Increased use has the potential to undermine ecological sustainability within the ravine. To protect the resource from becoming further compromised, the City requires strategic direction on the management of the ravine’s natural heritage resources and recreational uses and this constitutes the purpose of this Management Plan. 1 .2
Structure of the Manag gem gement Plan
The Glen Stewart Ravine Management Plan is comprised of three main components: •
An Executive Summary
•
A Technical Report
•
A number of Technical Appendices
1 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
The Executive Summary pro provides:: •
An overview of the study process;
•
A summary of the findings of the inventory, resultant management recommendations, and implementation strategy; and
•
A tool to direct the reader to specific sections within the Technical Report and Technical Appendices where additional detail related to specific components of the plan is provided.
The Technical Rep port pro prrovides: •
A concise description of the study process;
•
A description of the state of the Glen Stewart Ravine environment and the issues that need to be addressed through the future management of the ravine landscape;
•
A description of the goal and objectives for the management of Glen Stewart Ravine;
•
A discussion of alternative approaches to the management;
•
A presentation of optional management concepts as well as the preferred concept that was selected through a process of City and stakeholder review and public consultation;
•
Management prescriptions to address trail related issues (Trail Management Plan) and environmental issues (Ecological Management Plan);
•
A strategy to direct the implementation of the various prescriptions. This strategy addresses the implementation priorities and assigns roles and responsibilities; and
•
A program to direct the longterm monitoring of the ravine landscape, including trails and natural heritage features and functions.
The Technical Appen dic pend dices iinclude: •
Detailed inventory information that formed the basis for the Management Plan;
•
The reports of the subconsultant experts on the study team;
2 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
•
Glen Stewart Ravine Management Plan
OCTOBER 2008
Other background information that informed the development of the Glen Stewart Ravine Management Plan; and
•
Detailed design guidelines and recommendations.
1..3
Purpose of the Mana agementt Pllan
The Management Plan has been prepared for the purpose of providing strategic direction to the City of Toronto to guide the management and use of Glen Stewart Ravine. To achieve this the Management Plan is designed to: •
Be used as a guide, identifying current issues of concern and recommending strategies to address each;
•
Remain consistent with the goals and objectives that serve as the basis for the Natural Heritage policies in the City of Toronto’s Official Plan;
•
Remain dynamic to accommodate change over time in the ravine landscape, patterns of use and as maintenance needs evolve;
•
Set out recommendations to guide the protection and enhancement of the ecological functions and natural characteristics of the ravine landscape over time;
•
Respond to recreational activities that have been identified as important to the community while achieving core ecological objectives identified through the inventory stage of the study process;
•
Provide direction to guide the management of direct and indirect impacts associated with use on the ecology, stability and character of the ravine;
•
Establish guidelines to direct the management and maintenance of the natural system while providing recommendations to guide appropriate human interaction within the ravine landscape, ultimately strengthening the ecological integrity of the ravine and providing a healthier and safer environment for public recreational and educational use;
•
Include an implementation and monitoring strategy; and
•
Identify the potential roles and responsibilities of the City, its partner agencies, and the potential roles of the various user groups that have a stake in the sustainable management and use of the ravine environment.
3 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
1..4
Glen Stewart Ravine Management Plan
OCTOBER 2008
Go oal and Obje b ectives
The Management Plan was generated to achieve the following goal:
Develop an integrated longterm management strategy to protect, enhance and restore the ecological, hydrological, geological and recreational functions of the ravine in an environmentally sensitive and economically sound manner. The management objectives which will ensure that this goal is achieved and upon which the management plan is founded include 4 trailrelated initiatives and 12 ecologicalrelated initiatives described below. Trail Related M b bjectives Management Obje A.
Mitigate risks to users and provide a safer ravine environment.
B.
Manage informal trails (see fig 9: Technical Report) by deterring public access to sensitive areas within the ravine to facilitate restoration of degraded slopes and impacted vegetation communities.
C.
Improve condition of primary trail (see fig 9: Technical Report) to provide safe access through the ravine and mitigate impact on soils, vegetation and surface and groundwater resources.
D.
Protect and enhance native shrub layer and native ground plane vegetation communities adjacent existing trails.
Ecollogica al Rellated Mana agem ment Obje b ectives A. Maintain the longterm health of native trees within Glen Stewart Ravine and promote optimum conditions for regeneration. B. Mitigate erosion and soil compaction around tree roots. Protect root zones and restore compacted and eroded soils around tree roots where these conditions are affecting tree health and stability. C. Promote diversity of vegetation, as diversity of vegetation will give rise to diversity of other life. D. Promote species diversity. Enrich diversity of plant species within the ravine as a means to enhance overall biodiversity. E. Manage habitat. Enhance the diversity of wildlife species through habitat protection, enhancement and/or creation. F. Increase security for wildlife. Sustain sensitive species and ground nesting species to enrich species diversity.
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Glen Stewart Ravine Management Plan
OCTOBER 2008
G. Protect Ames Creek and restore seepage areas impacted by human traffic to enhance habitat and sustain moistureloving plant communities. H. Restore and enhance floodplain vegetation community. Enhance stability of floodplain and establish a diverse vegetation community within floodplain. I. Improve vegetation community along adjacent roads and. Improve functionally protective effect of vegetation that is located along roads and private properties that abut Glen Stewart Ravine (as dense edges protect forest from drying winds, dust and excess light). J. Stabilize steep and unstable slopes utilizing aggressive rooting vegetation. K. Enhance overall diversity, function and ecological integrity of the degraded area located at the north end of the ravine. L. Manage invasive species. Promote biological diversity and enhance opportunities to establish robust native plant communities. The 16 objectives provide the basis upon which management plan prescriptions have been developed. The prescriptions essentially describe the actions recommended to be implemented to address concerns within the ravine. The concerns are identified in section 1.7 of the Executive Summary. Tables 15 in section 1.14 of this document relate the prescriptions to the objectives above. Prescriptions are arranged in priority order (for immediate and short term actions) and are referenced with a code to various Management Plan maps provided in section 1.14. 1..5
Manageme ent Pla an Deve elopmen nt Proce ess s
The following process was completed by the multidisciplinary study team in the course of preparing the Management Plan: •
Review of background information
•
Inventory and assessment of site features and functions
•
Identification of issues, opportunities and constraints
•
Review of progress and findings with City of Toronto
•
Presentation of findings and issues to stakeholders
•
Receipt of feedback from stakeholders
•
Definition of general direction for Management Plan (draft)
•
Development of Management Options and Selection of a Preferred Option
•
Development of SiteSpecific Rehabilitation Plans
5 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
•
Glen Stewart Ravine Management Plan
OCTOBER 2008
Development of final Management Plan and Implementation Strategy
1 .6
Publi b blic Consultation
A key component of the Management Plan study process included community consultation and education which included: •
Installation of temporary signs at various locations throughout the ravine to identify important aspects of the ravine landscape and existing issues of concern;
•
Preparation of a brochure by the study team which had a similar intent to that of the signs and which was mailed out to nearly 4000 residents (a copy of each sign and brochure are included in Appendix D); and
•
Two public meetings that were held at strategic stages of the process with the intent of: •
Introducing the project and planning process to stakeholders;
•
Confirming current use patterns and preferences within the ravine;
•
Identifying key issues and opportunities that should be addressed;
•
Presenting the findings of the preliminary inventory and assessment;
•
Seeking community feedback on the goal and objectives for the Management Plan;
•
Presenting and discussing conceptual management options and the priorities, benefits and constraints for each. Options addressed issues of concern related to: •
Restoration and management of existing vegetation communities and habitat;
•
•
Trail delineation and recreational use; and
•
Erosion and slope stabilization.
Providing an opportunity for public review of the conceptual management options and assist in the process of selecting a preferred option;
•
Present a preferred approach to the community and stakeholders for review; and
6 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
•
Glen Stewart Ravine Management Plan
OCTOBER 2008
Including children in the education process by providing in class sessions and a site walk;
The community provided verbal and written responses which the study team ultimately used to refine the Management Plan. Responses from the participants who attended the two meetings are documented in Appendix C. 1..7
Sitte Inve enttory and Anal lysis
Section 7.0 of the Management Plan Technical Report document provides a detailed description and mapping of existing conditions within the ravine based on the inventory and assessment work completed by the study team. It summarizes issues of concern and recommends some general approaches to resolve these issues. Detailed prescriptions for management actions are provided later in the document in Section 10.3. The inventory and analysis section is accompanied by a photographic inventory found in Appendix F: Technical Report and includes maps to illustrate where the areas of concern are located within the ravine. The inventory and analysis of the ravine landscape is described based on the following categories: 1. Vegetation communities 2. Invasive species 3. Management of tree health 4. Drainage features 5. Steep slopes 6. Soil erosion 7. Structures 8. Access and use 9. Interpretation The following sections summarize the findings of the review and assessment stage of the project. The findings were used as a basis from which management options were derived.
7 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
1..7.1 1 Vegetation n Comm muniities s Glen Stewart Ravine is classified as an Environmentally Sensitive Area and is comprised of three vegetation communities. DryFresh Red OakMaple Forest predominates with a small pocket of DryFresh HemlockSugar Maple Mixed Forest occurring in the south east and a narrow swathe of cultural meadow following the streamcourse. This data is important to the Management Plan because it provides an indication that the vegetation has arisen because of environmental factors that were present before the advent of human interference. The communities are mapped in Figure 2: Technical Report and additional mapping illustrating this inventory information is provided in Appendices A and B: Technical Report. Much of the canopy and subcanopy layers of vegetation within the ravine were found to be in fairly good condition. Some concerns that were identified through the inventory stage of the work program include the following: •
A lack of awareness by community of ecological sensitivity within ravine;
•
Impacts on forest habitat by urban pets specifically unleashed dogs and cats
•
Presence of invasive nonnative plants (Norway maple, garlic mustard, black swallowwort);
•
•
Presence of discarded food that presents the potential to: -
Affect behaviour of wildlife
-
Make animals sick
-
Attract parasites and urban predators like skunks and raccoons
Signs that the herbaceous layer is being threatened by invasive species (that are outcompeting and shading out native species) and trampling as a consequence of foot traffic. This latter condition is more significant on steep slopes where soil erosion is evident.
Recommendations: Given the current impacts from trampling and if left unmanaged, the quality of habitat will diminish along with the diversity of flora and fauna. Therefore, it is recommended that a restoration strategy be developed to enhance biodiversity and control invasive species. One option is to encourage light penetration to the forest floor by creating small openings in the tree canopy to encourage new
8 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
growth that will contribute to the sustainability of the ecology of the ravine and protect it from further decline. This option requires monitoring and intensive management of invasive species as these opportunistic species will also take advantage of the additional light. 1..7.2 2 Inva asive i Speciies NorthSouth Environmental Inc carried out an assessment of native and non native species within the ravine in Spring, 2007 and found there to be concentrations of Japanese knotweed, Garlic mustard, Manitoba maple and Norway maple. Clusters of nonnative trees including Norway and Manitoba maple, inhabit the edge of Glen Manor Drive. These species have the ability to suppress the native understorey species by outcompeting native plants for moisture, nutrients and available light. If uncontrolled, these species can dominate the ravine landscape, decreasing biodiversity and suppressing natural successionary processes. Concentrations of invasive species are illustrated on Figure 3: Technical Report. Recommendations: A strategy to progressively remove species from the ravine environment is provided. Over time it is recommended that the preparation of a more detailed and uptodate map of the location of invasive plant species within the ravine be undertaken as the Management Plan is implemented. Specifically, invasive species management will need to be addressed at ravine edges and clearings in the canopy to ensure the longterm sustainability of a diverse native forest community within Glen Stewart Ravine.
1.7.3 Management of Tree Health The City of Toronto currently manages risks associated with trees. A biannual review of the ravine is conducted to identify potential trees that pose a risk for trail users and potential impacts on private property related to tree structure and health. The assessment helps determine the need to implement subsequent actions such as topping, dieback removal, pruning, removal of broken branches and debris. Through this, the City recognizes that a total elimination of all risk related to trees is unrealistic, however, appropriate management and risk reduction are attainable. Through an independent review conducted by Urban
9 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
Forest Innovations Inc in January, 2007 it was determined that risks stemming from: structural weakening or destabilization, presence of dead branches, rot or disease, soil compaction and root exposure occurring as a result of erosion, had been well managed by the City along primary trails and over stairways within the ravine. The extent of internal decay, however, is a risk that is not easily detectable and in the cases of large mature trees can continue to pose a safety concern for users of adhoc trails as in these circumstances soil tends to be compacted or eroded near the tree and roots exposed, potentially weakening the tree. In fact, the findings of the assessment determined that many adhoc secondary trails coincided with locations where individuals and groups of trees are showing evidence of declining health, dead branches and/or structural problems and hence pose potential safety concerns. Tree management issues are illustrated on Figure 4: Technical Report. Recommendations: Recommendations address adhoc trail use and soil compaction issues are provided within the Management Plan. Recommendations for improvements to the design of the primary trail are also provided to mitigate potential future impacts on trees. Restoration of the vegetation community to promote the natural regeneration of native trees and protect and enhance biodiversity is also an important way to ensure a healthy and thriving forest. 1..7.4 4 Draiinag ge Feattures See epage a Parts of the lowlying areas of the ravine are located within the flood plain of Ames Creek. Where the edges of the floodplain meet the steep slopes of the ravine, seepage is present. Seepage originates on the surface of slopes, pools in low lying areas and supports moistureloving plants and wildlife, and enhances water quality. Areas prone to seepage were mapped in the Spring of 2007 by North South Environmental Inc (refer Figure 5: Technical Report). In some cases, where trails traverse seepage areas, muddy conditions and trail widening have occurred as users attempt to avoid the wet areas of the trail. In winter, when the water freezes over the trail surface, ice poses a hazard. Trampling of seepage areas impacts sensitive wetland plant communities and contributes to a loss in diversity of the vegetation community.
10 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
Recommendations: In response, the Management Plan sets out alternative solutions to address conflicts between trails and seepage areas as well as trail design recommendations to avoid muddy and icy trail conditions caused by the discharge of water from seepage zones. Design alternatives can be found in Appendix E: Technical Report. 1..7.5 5 Draiinag ge Feattures – Ames Cre eek k Ames Creek winds through the ravine’s north section originating from a natural spring at the north end of the site. This watercourse continues to be fed throughout the length of the ravine by discharge along the base of the slopes and from within the floodplain. The natural source of flows to this creek is a unique feature of ravines in Toronto and should be protected. However, the following issues of concern were identified as a product of the inventory process: •
A lack of riparian woody cover combined with erosion from trail use and trail widening near the creek appears to be affecting the integrity of the streambanks;
•
In locations where the stream adjoins steeper slopes, weakening of the toes of the slopes has occurred; and
•
Some slopes have been undercut; this is a concern when the condition occurs next to a trail.
Recommendations: The Management Plan provides recommendations to mitigate potential erosion at the interface between the trail network and the creek through improvements to trail design and the implementation of biotechnical stabilization solutions that employ vegetation as the primary stabilization mechanism where avoidance of conflicts through the realignment of the trail is not an option. This approach will also assist in establishing woody riparian cover. 1.7.6 Steep Slopes There are a number of steep slopes within the ravine (refer Figure 6: Technical Report), some with a gradient of 1V:2H or greater. In some cases, slopes of this
11 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
magnitude have been impacted by erosion and exhibit a lack of vegetation cover. The following concerns need to be addressed in these cases: •
Trampling is impacting the health of the vegetation upon which the slopes depend on for stability;
•
Soil compaction and root exposure (refer photos 12, 35, 38: Appendix F: Technical Report) has the potential to destabilize trees and further undermine the stability of slopes over the longterm creating the potential for risks to trail users and adjacent private properties that are located beyond the top of slope.
Recommendations: The Management Plan recommends that the slopes be monitored in the short term (over the next 5 years) and that appropriate longterm slope stabilization methods be developed (refer Appendix B). The process of establishing future capital budgets must consider slope assessment and stabilization requirements in order to address potential public safety considerations and to ensure that the ravine slopes remain stable over the longterm. Slopes in the order of 1V:2H and steeper should be assessed on a sitebysite basis to determine the extent to which potential retrogression might affect adjacent properties and the propensity of the slopes to fail should nothing be done to stabilize them in both the short and long terms. 1..7.7 7 Soil Erosio o n There are areas within the ravine where ground flora has been impacted by trampling and soil compaction. Soil loss has occurred as a result of sheet runoff and erosion. These conditions have the potential to contribute to slope instability over the long term if left unmitigated. Gully erosion is also occurring in the crevices between the ravine slopes and is caused by soil migrating through groundwater discharge areas. This condition could weaken the toes of slopes, a condition that may inturn result in the future slumping of slopes (refer to the geotechnical report in Appendix B: Technical Report for a detailed assessment of soil erosion and slope conditions. Also refer mapping Figure 7: Technical Report).
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Glen Stewart Ravine Management Plan
OCTOBER 2008
Recommendations: Efforts should be made to restore a robust native vegetation community in areas experiencing acute erosion. Where undisturbed forest areas exist within the Glen Stewart ravine, these areas should be left in a natural state as much as possible with the objective of protecting and promoting the regeneration of naturally occurring ground flora. 1..7.8 8 Struc ctures – ber Retain ning g Wa alls s Tiimb Retaining structures that were built to control the surface flow of water and prevent slope erosion continue to function. However, an assessment of these structures carried out by a qualified structural engineer on the study team, has determined that the structures are approaching the end of their serviceable life (refer Figure 8: Technical Report). Recommendations: Slope stabilization measures should be implemented to replace these existing retaining structures in order to enhance longterm slope stability. Soft biotechnical solutions, reliant on planting should form the primary stabilization element where possible. Existing timber retaining structures should be phased out as replanting strategies on slopes takes effect over time.
1..7.9 9 Struc ctures – Sttairs and Boardwalks Wooden stairs and boardwalks (refer photos 11, 29, 31, 33: Appendix F: Technical Report) installed in the early 1990’s are becoming unstable as a result of soil erosion and material degradation. The areas around the stairways are being impacted by foot traffic, contributing to soil erosion which inturn results in the undermining of the integrity of the existing footings. Two existing footbridges (refer photo 17: Appendix F) do not meet the requirements of the Ontario Bridge Code and are not suitable to provide access for City of Toronto maintenance and emergency vehicles. Recommendations: To improve safety, the Management Plan recommends that stairways be replaced/upgraded as soon as possible to mitigate erosion and address potential public safety concerns and that a more robust and sustainable design
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Glen Stewart Ravine Management Plan
OCTOBER 2008
be employed using either concrete or steel footings and substructure. It is recommended that the implementation of replacement staircases be completed over the next 2 to 6 years. Slopes adjacent the stairways will require barriers to prevent users from short cutting up/down the slopes (refer photo 12: Appendix F). In these areas, restoration plantings are recommended to enhance slope stability. The two bridges should be replaced within the shortterm (over the next 5 years) with more robust structures that achieve the above noted requirements. Further geotechnical investigations should be carried out to determine if more substantial slope stabilization measures are required to ensure the longterm integrity and protection from risk of properties upslope. Options related to the design of replacement structures within the ravine are provided in Appendix E. 1..7.1 10 Acces ss an nd Use The ravine is highly valued by the community as a recreational asset, however, intensive use over the past decade has placed increasing pressure on the ecology of Glen Stewart Ravine. People have been accessing the slopes of the ravine in an uncontrolled manner resulting in the creation of adhoc trails. The trails are illustrated on Figure 9: Technical Report). This has contributed to soil compaction, erosion and undercutting of the surface soil layer which inturn can result in the exposure of tree roots and potential destabilization of trees. In addition, although Glen Stewart Ravine is designated as an area where dogs must remain on a leash, roaming offleash dogs are of particular concern and this situation occurs frequently. Uncontrolled access to the ravine slopes has enabled unleashed dogs to trample over delicate plants on the forest floor. Repeatedly, this can affect the ability of the herbaceous layer, which helps to retain soil through fibrous root systems and moisture, to survive. Other activities are impacting the character and health of the ravine landscape including dumped garbage, vandalism and invasive species planted in private gardens adjoining the ravine.
14 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
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Recommendations: The Management Plan sets out the recommendations that these activities be curbed through the provision of education, fencing, interpretive programming, enforcement and signage. The Management Plan addresses access requirements throughout the ravine, defines appropriate uses and provides recommendations to mitigate uncontrolled uses within the ravine through the closure of adhoc trails and incorporation of deterrents to restrict access to sensitive areas. 1..7.1 11 Interrpretattion There is an opportunity to enhance the trail system within the ravine by incorporating signage and artwork that celebrates the unique environmental and cultural significance of the ravine and local area. Themes could be based on the following: •
The fact that archaeologists have found artifacts near the Glen Stewart Ravine that date back to about 4000 years ago;
•
The ravine’s geologic history which dates back to the last Ice Age and is a remnant of the Iroquois Shoreline; and/or
•
The fact that in the early 1900’s the ravine encompassed a pond that was approximately a half an acre in size, created by a dam. The dam existed until a drowning resulted in a public protest that forced its removal.
1..8
Manageme ent Option ns
Based on the findings of the inventory and analysis, alternative management options were prepared. The strategies synthesized the findings of the inventory and assessment and incorporated input from stakeholders and City staff to define preliminary approaches for the management of Glen Stewart Ravine. The benefits and constraints of each alternative approach were compared and evaluated based on their respsective performance, practicality of implementation and anticipated cost implications. This process ensured that the best alternative was chosen to satisfy ecological objectives and address the needs of the City and the community. •
Each alternative management option was evaluated based on its potential to achieve the following objectives:
•
Improvement of public safety addressing:
15 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
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-
Vandalized structures and signs
-
Existing remnant posts and infrastructure
-
Exposed metal and reinforcement bars
-
Dumped household waste
-
Missing handrails and treads on stairs
-
Instability of existing structures
-
Trip and fall hazards
•
Trees that potentially pose a risk to primary trail users
•
Replacement of degraded structures
•
Protection and enhancement of the natural ravine environment;
•
Enhancement of safe public access within and through the ravine;
•
Improvement of the primary valley trail focusing on remediating trail specific issues;
•
Regeneration of the forest ecology;
•
Remediation of steep slope sites and erosion;
•
Mitigation of impacts resulting from the establishment of secondary trails;
•
Mitigation of access to sensitive sites within the ravine;
•
Provision of opportunities to engage users with the natural environment and educate users about the sensitivity of the ravine’s microenvironments, natural drainage features and the interrelated natural cycles; and
•
Management of the potential impacts of increased use on the natural environment and is reliant on varying degrees of economic resources and staff commitment to implement its recommended management directives effectively and efficiently.
The alternative management concepts emphasized one of three basic management approaches each of which has a direct correlation to funding implications over the short and long terms: ess 1. Approa p ach 1:: Managing Public l Acce s Restricts public access to areas that are least resilient to human activities and impact as well as those that are targeted for intensive restoration. This option is most cost effective longterm. 2. Approa p ach 2: Physic s cal Improvementts – Promotes physical improvements to accommodate expected levels of use within sensitive areas of the
16 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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ravine over the longterm. Requires robust infrastructure and highest one time upfront costs but reduced investment in longterm maintenance. 3. Appr gem p oach 3: Active Manag gement – Promotes ongoing
active
management activities to mitigate the anticipated impacts of use on the natural environment. Upfront costs are reduced but requires a long term funding commitment for maintenance and monitoring. 1..8.1 1 Manageme ent Option n ‘A’ Option A emphasizes the “physical improvement” approach to address public access and use of the ravine and protect eroded slopes and sensitive sites. The management option is comprised of the following components: 1. Creation of a narrower looped nature trail within the ravine, providing the opportunity for short and longer exercise circuits through different parts of the ravine. 2. A wider trail along the valley floor with granular surface. 3. The installation of a post and wire mesh fence on both sides of the nature trail for the entire length of the trail is proposed to limit public access to the sensitive sandy slopes of the ravine and sensitive vegetation community. Bene efits 1. Provides choice of trail experiences and enables access through interesting sections of the ravine, enhancing educational opportunities; 2. Creates a looped recreational trail through the ravine that will afford recreational opportunity for users; 3. Closes segments of secondary trails which are impacting the ecology of the ravine the most and facilitates restoration of these areas with native plantings; and 4. Facilitates the upgrading of the less impactful segments of secondary trail to enable users to observe regenerating forest areas, creating a further opportunity to achieve educational and interpretive objectives.
17 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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Legend d
Primary trail
Seepage area
Closed secondary trails
Retaining structures
Steep slopes
Figure 1: Management Option ‘A’
18 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
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Constra aintts 1. Requires significant initial investment to construct improvements to primary and secondary trails. This work would include extensive slope stabilization and the implementation of structures to mitigate erosion where segments of the secondary trail cross seepage areas and steep slopes; 2. The secondary trail crosses steep slopes requiring extensive stabilization works. 3. The existing log crib slope structure is failing. Slope remediation is required. Erosion at the top of the slope requires mitigation. 4. Potential future slope stabilization concern at these locations. 5. Trail crossing of drainage features requires improvement. 6. Multiple tree hazards exist within the area of the secondary trail. 7. Will result in an increase in the length of trail requiring maintenance and the need for additional effort to manage risks related to slope stability and tree health/stability;
8. Primary and secondary trails will require fencing both sides for their full length to prevent access to steep slopes and/or areas where safety concerns related to tree health may exist. 9. Due to higher initial capital costs, potentially less funding could be made available in the short term for the replacement of bridges and stairways. Antic cipated a d C Capitall Cost The estimated capital cost of the implementation of Option ‘A’ is $ $849, 500. 1..8.2 2 Manageme ent Option n ‘B’’ Management Option B is focused on promoting ‘active management’ to stabilize heavily eroded and restore sensitive areas. This management option is
comprised of the following components: 1. Closure of all secondary trails that traverse slopes within the ravine. 2. The primary trail would be ‘flood proofed’ and specially designed to deal with crosssurface flow, seepage areas, and the steeper grades that occur along sections and the trail.
19 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
3. Stabilization and restoration of the most heavily eroded sites utilizing bioremediation techniques. 4. Securing of the slopes utilizing post and wire fencing along segments of the trail to prevent access to the most sensitive areas of the ravine. 5. To further address safety concerns and environmental impacts, access from Glen Manor Dr down the west valley slope would be restricted using discreet fencing set back from the boulevard and installed slightly below the elevation of the top of bank. Bene efits 1. Provides an effective and efficient means to manage risk to trail users arising from impacted/structurally weakened trees and potential slope failure through the closure of all secondary trails; 3. Enhances biodiversity within the ravine through the replanting of closed trail alignments with native trees and herbaceous plants; 4. Achieves reduction in longterm management effort associated with impacts generated by user creation of/access to secondary trails;
5. Results in a reduction in the amount of trails requiring maintenance and a reduced requirement for slope stabilization work that makes overall implementation more viable for the City; and 6. Provides a more practical means to stage the implementation of restoration efforts. Since larger areas of the ravine will be closed to the public, it would be easier to address a multitude of issues in any one given area such as invasive species management, soil compaction, tree root exposure etc.
20 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
Legend
Primary trail
Seepage area
Existing secondary trails to be closed Retaining structures
Steep slopes
Erosion areas
Figure 2: Management Option ‘B’
21 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
OCTOBER 2008
Constra aintts 1. Limits the availability of funds to carry out restoration works until structures are replaced and slopes are stabilized; 2. Limits trail choices and recreational opportunities as well as limiting user experience and interpretative potential; and 3. The reduced extent of fencing may not fully discourage public access to sensitive slopes and additional fencing may be required in the long run. Antic cipated Capitall Cost a d C The estimated capital cost of the implementation of Option ‘B’ is $1,099,500. 1.8.3 Preferred O Opti ption Developed from the alternative approaches, a Preferred Option was generated and endorsed by the community and City staff. The Preferred Option is most consistent with Management Option ‘B’ and provided the direction upon which the Glen Stewart Management Plan was based. Refinements were made to the Preferred Option in order to address community, agency and City staff comments and a catalogue of recommendations was generated to address structural
improvements
and
management
initiatives.
The
structural
improvements and management initiatives met the objectives established in the early stages of the study process and address the specific issues identified through the completion of the background review, site assessment and public consultation processes (refer section 1.7 of the Executive Summary). 1 .9
Glen Stewart Ravine Manage ement Plan
The recommended Management Plan is comprised of two integrated components – a Trail Management Plan and an Ecological Management Plan. Both plans are fully integrated and offer the following benefits: •
Mitigation of risks to public safety;
•
Minimization of requirement for further capital improvements;
•
Minimization of longterm maintenance requirements;
•
Encouragement of passive recreational use of trails;
•
Provision of a linkage between residential neighbourhoods across the ravine;
•
Mitigation of further impacts to trees and sensitive understorey plants; and
22 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
•
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Maximization of the potential to restore degraded vegetation/ eroded slopes.
Each component of the Management Plan is guided by the objectives set out in Section 1.4 of the Executive Summary and identifies a set of actions (prescriptions) to be implemented to achieve those objectives. 1..9.1 1 Trrail Mana agementt Pllan The Management Plan recommends the following actions be implemented to assist in achieving the safety and access objectives identified for Glen Stewart Ravine: 1. Close secondary trails and implement closure barriers; 2. Monitor and manage tree hazards to reduce risks to trail users and adjacent properties; 3. Deter further creation of additional secondary trails through the installation of new plantings; 4. Mitigate impacts by foot traffic to sensitive slopes, vegetation and drainage features through the installation of barriers, brush bundles and plantings; 5. Mitigate compacted soil surfaces and restore these areas with native vegetation; 6. Improve the primary valley trail focusing on remediating trail specific issues; 7. Provide interesting and educational trail amenities such as signage and artwork along trails; 8. Focus on improving existing surfaced trail locations where appropriate rather than disturb other areas of the valley; 9. Maintain and enhance primary public access points into the ravine; and 10. Monitor and maintain the condition of trails, fencing and structures.
23 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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1..9.2 2 Ecollogica al Managementt Pllan The Management Plan recommends the implementation of the following actions to assist in achieving the ecological objectives identified for Glen Stewart Ravine: 1. Provide optimum conditions for regeneration of native tree species through the removal of nonnative species, canopy clearing or remediation; 2. Implement solutions to deal with erosion and compaction of soils around tree roots where it has the potential to threaten tree health; 3. Promote structural diversity in the canopy, subcanopy and ground layers. Restore ecological sustainability through natural regeneration and enhanced biological diversity; 4. Promote species diversity; 5. Improve diversity of vegetation for wildlife use; 6. Provide increased diversity of microhabitats; 7. Provide increased security for wildlife; 8. Promote germination of native plants on seepage slopes; 9. Restore and enhance vegetation assemblage on floodplain; 10. Improve buffering function of vegetation adjacent to Glen Stewart Ravine; 11. Promote structural diversity in canopy, subcanopy and ground layer on steepest slopes; 12. Improve vegetation cover on steepest slopes to help reduce erosion; 13. Reduce populations of invasive species; 14. Allow for natural fluvial processes of the stream course and ground seepage to occur; and 15. Monitor the status of the vegetation communities, restoration plantings and habitats.
24 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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1..10 Manageme ent Prescriptions s Specific management prescriptions are listed in Tables 15. They achieve the various shortterm and longterm management objectives identified through the study process (refer section 1.4). The prescriptions have been organized into trailbased improvements and ecologicalbased initiatives to meet the following three objectives: 1. The prescriptions direct improvements to the trail network within Glen Stewart Ravine. These improvements are aimed at enhancing appropriate public access through the ravine while ensuring that important ecological features and functions and sensitive sites within the ravine are appropriately protected. 2. The ecological management prescriptions are also aimed at protecting and restoring existing ecological features and functions that have been impacted/ degraded over time from use to enhance the ravine ecosystem through management over the long term to ensure its sustainability. 3. The prescriptions are aimed at enhancing public safety. The prescriptions are identified in Tables 15: Section 1.12 which outline the timing associated with the implementation of each trailbased and ecological based management prescription. Detailed design guidelines for various prescriptions are provided in Appendix E. 1..11
Implementattion Priioritie es
Setting implementation priorities for the various prescriptions will assist the City in the process of making choices based on the anticipated benefits and cost considerations associated with the implementation and maintenance of each recommended management prescription. Short, medium and longterm implementation priorities have been defined in relation to cost implications and user needs and the actual staging of their implementation is incumbent on funding and the potential to mobilize volunteer assistance. Tables 15 below describe the various management prescriptions in relation to their priority for
27 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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implementation and provide information regarding the sequencing, timing and cost of implementation. It should be noted that the process of implementing prescriptions requires some flexibility. For example, there are a multitude of high priority prescriptions that need to be addressed all at once in either the immediate or short term. As well the process needs to consider the practical implications of construction with respect to site access limitations, the fact that there is only one atgrade level entry in the southern end of the ravine, and the need to transport materials equipment within the ravine. Works are therefore, required to be implemented in the most remote areas of the ravine before those that are proposed in the vicinity of the access point to ensure that completed works are not impacted by the movement
of
equipment
later
in
the
implementation
process.
The
implementation of the various priority prescriptions, once funding is confirmed for each implementation cycle, should be made with regard for this consideration. Implementation priorities have been set out to address short term risk management as well as some predominant objectives that are important to achieve within both the short and longer terms to benefit the overall ecological sustainability of Glen Stewart Ravine. These initiatives include the stabilization and restoration of slopes and the ongoing monitoring and management of tree health. 1..11.1 Manageme ent Prescription s Prioriity Tables s The following sections describe the actions (prescriptions) recommended to be implemented to address concerns within the ravine. The concerns are identified in section 1.7 of the Executive Summary. The prescriptions have been organized into groups according to when they are to be implemented immediately, in the shortterm, mediumterm or longterm. To help locate the action items within the ravine, they are illustrated on maps (Figures 59). The prrescrip ptions on the maps s
rela ate the acttions s to 16 objec ctive es which the actio ons s are sett out to achieve (managem ment obj e liistted in sectio on 1.4). Prescriptions on the maps are b ectives are referenced with a code, where in the example TMPA5:: TMP = Trail Management Plan A
= Objective A
28 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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5
OCTOBER 2008
= Prescription 5
Detailed design recommendations are provided in Appendix E: Technical Report and guide the implementation of prescriptions. 1..11.2 Immediate Prioriities s ears 02 ye There are a number of actions that can be immediately implemented without substantial investment, both in terms of financial resources and staff effort to improve public safety and enhance the ecological health of the ravine. The immediate priorities are identified in Figure 5.
29 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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1..11.3 Short Te erm Prioriities s nagem men nt and Public c Safety – 26 Years s Risk Man A primary objective of the Management Plan is to reduce risk of injury to trail users. Initiatives that address risk reduction and public safety should be addressed in the shortterm as determined by financial implications. Consequently, initiatives that address immediate or potential future risks to public safety have been assigned the highest priority. High priority initiatives include:
• Management of trees that pose a risk to trail users; •
Closure of poorly defined or informal trail alignments which traverse potentially dangerous site conditions ie. steep slopes;
•
Addressing situations or structures that present potentially unsafe conditions; and
•
Repair of the trail where there is potential of slipping or tripping.
The shortterm priorities recommended to be implemented to mitigate risk and enhance public safety are identified in Figure 6.
31 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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1.11.4 Short Term Priorities – – Slope Stabilization – 26 Years Initiatives which address slope instability and which are aimed at mitigating potential future slope failure have been assigned a high priority. Implementation actions to address the priority include: •
Undertaking geotechnical investigations with the objective of determining potential risks and recommending long term solutions.
•
Reinforcement of the steepest slopes within the ravine nearest residential properties, primary trails and slopes that show signs of slumping;
•
Mitigation of further impacts of surfacial soil erosion on slope stability through the implementation of improvements; and
•
Prevention of erosion of trail surfaces by limiting access to sensitive slopes and groundwater discharge areas.
This
management
priority
requires
both
short
term
and
longterm
implementation efforts. The capital budget to address all the stabilization and slope restoration works required within the ravine will likely not be accommodated within one funding cycle. Therefore, the stabilization of the most heavily eroded slopes adjacent to properties or trails within the ravine should be addressed first. The implementation of associated drainage works should also be addressed at this stage. A number of design recommendations are proposed to address stabilization and can be found in the detailed design guidelines of the Technical Appendices (Appendix E: Technical Report). The shortterm priorities recommended to be implemented to enhance slope stabilization are identified in Figure 7.
33 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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1.11.5 Mediu – 510 years dii um Term Priorities – Impro p provements tto Existi sting Trails – Medium term priorities include improvements to the existing primary trail to provide enhanced recreational opportunities, improved serviceability and all season accessibility ensuring the longterm enjoyment and usability of the ravine by the community. Future environmental impacts will be mitigated through the implementation of a sensitively designed, functional trail that accommodates demands for recreational use within Glen Steward Ravine. In addition, improvements to the primary trail system will help compensate for the closure of numerous trails on the east side of the ravine. To encourage use of the primary trails, several improvements will be required. These should include: •
Replacement of two footbridges and the construction of one additional footbridge designed to accommodate City maintenance and emergency services and should be constructed in accordance with current standards and codes.
•
A trail design that addresses trail widening and the sensitivity of drainage features/ seepages by providing a well demarcated path, allweather surfacing and a proper base course and additional drainage layer.
•
A drainage swale or drainage pipes and culverts should be utilized to convey water beneath/ across trails without undermining.
•
Improved linkage between neighbourhoods across the ravine as requested by the community, by way of a formalized access from the west off Glen Manor Rd (south west corner of ravine) across the creek and linking to the primary trail.
In addition, the four main access points that access the primary trail, should be upgraded with garbage bins, benches, improved signage and hard surface paths that connect stairways to sidewalks. Benches and interpretive signs should be installed at strategic locations along the primary trail to educate users as to the geologic, hydrological and ecological significance of the ravine in the context of a larger natural heritage system in Toronto.
35 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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1..11.6 Lon ng Term m Priorritties onm men ntal Sustai 0 20 ye earrs Enviiro s inability – 10 Protection of the longterm ecological integrity of the ravine is a key objective in addition to the protection and restoration of ravine slopes and floodplain seepage. The implementation of specific vegetation and habitat enhancement initiatives is required to ensure the longterm ecological sustainability of the ravine landscape. Specific implementation actions include: •
Mitigation of existing impacts to discharge zones and degraded natural drainage features;
•
Mitigation of compaction and erosion and forging of multiple trails on slopes;
•
Mitigation of understorey loss & decline in significant vegetation communities;
•
Prevention of further impacts to trees and consequent decline in tree health and resultant tree loss;
•
Removal of invasive species from canopy and subcanopy vegetation layers;
•
Restoration of native vegetation communities
Invasive species management and restoration planting works should commence on slopes exhibit degraded conditions such as presence of invasive species. These areas may include sites which were impacted by secondary trail use. These activities should also occur in floodplain areas which may include creek banks and groundwater discharge areas. The following procedure should be considered when implementing this priority: •
Inspect trail closure barriers and fencing and supplement with more barriers/ fencing as required to ensure the prevention of access to restoration sites.
•
Compacted soils should first be loosened using manual techniques to mitigate further compaction impact on the roots.
•
A native seed mix should then be applied to areas with slopes of less than 5%. A combination of native stoloniferous shrubs, live stakes and herbaceous plugs should be planted on slopes exceeding a 5% gradient.
•
Restoration plantings on dry, steep slopes should include a temporary irrigation system or regular watering in the first two growing seasons of plant establishment (refer section 13.3.1 of the Technical Report).
•
A layer of decomposed wood mulch or locally collected leaf litter should be applied in an effort to retain soil moisture and reduce weed competition.
The longterm priorities recommended to be implemented to enhance ecological sustainability within the ravine are identified in Figure 9.
37 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
1..12
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Mainte enance and Moni itoring
An essential component of the Glen Stewart Ravine Management Plan is the commitment to ongoing, long term maintenance and monitoring to ensure that management objectives are achieved over the long term. The following recommendations should become part of the ongoing maintenance and monitoring program for the ravine. 1..12.1 Lo ongTer rm Mainte enan nce Initiative es g The following list can be used to secure further funding for maintenance and operations procedures that will be required to improve safety and access, ensure slope stability, improve ecological integrity in the ravine and enhance access and passive recreational use. The maintenance program outlined here corresponds to the implementation priorities in Section 1.13
Safety an nd Lia abilitty 1. Maintain handrails, decking, posts and connections. Promptly secure and/or replace degraded elements. 2. Maintain guard rails and ensure in good repair. 3. Maintain the condition of boardwalks for same elements as above. 4. Maintain the condition of footbridges for same elements as above. 5. Monitor the condition or existing retaining structures until all are removed or replaced with improved structures. 6. Maintain trail surfaces and eliminate trip hazards. Resolve sightline issues by pruning back encroaching vegetation. 7. Remove garbage regularly and promptly repair vandalized structures. 8. Provide routine inspection of trees overhanging trails once annually. Inspect for root exposure, frost cracks or any other structural damage, disease, rot and dieback. Slo ope Stabiliiza ation 1. Inspect bioengineered slopes twice yearly for the first 2 years then yearly thereafter. Inspect for differential settlement, slumping, integrity of rock revetments and toe armouring.
39 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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2. Routinely inspect restoration plantings on slopes for the presence of invasive species, damage by browsing animals, pets or human impact. This activity should be carried out biweekly until plant establishment (first 6 months). 3. Inspect restoration plantings for water requirements and mulch. Water regularly as required during plant establishment period (usually first two growing seasons). Top up mulch as required. 4. Inspect integrity of fencing that prohibit access to steep and sensitive sites and associated signage and replace if damaged. 5. Where drainage pipes and culverts have been installed, regular maintenance and inspection of the pipes is required. Blocked conduits should be cleared of debris in such a way as to avoid the flushing of sediments into the creek. Trrail Improv ments p vem 1. Inspect trail surface annually in spring for ruts that may pose a trip hazard. Patch and grade trails accordingly. 2. Avoid use of salt as a deicing agent on trails during the winter months as this can be harmful to the ravine ecology. To promote allseason access on trails a sandbased agent should be used. 3. Install and secure recycling containers at entry points to the trail system to encourage waste reduction. 4. Locate and secure trash receptacles at trail access points. 5. Maintain signage to ensure legibility. 6. Update community message board to ensure information is current. 7. Ensure trails and amenities are kept clean, litter is removed on an ongoing basis, and trash receptacles frequently emptied to avoid spill over. 8. Remove graffiti and tags promptly. Ecollogica al Sustain nability/ Restorat tion 1. Inspect fences seasonally to ensure wire mesh remains properly affixed to posts. Repair/replace posts and mesh that have been degraded. 2. Temporary fencing used to secure restoration sites should be left intact and maintained until plantings have become established and nonnative species are eradicated from the recovering understorey.
40 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
Glen Stewart Ravine Management Plan
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3. Inspect trail closure barriers seasonally to ensure that they remain intact. If deterrents are not working, install additional barriers or reinforcements. 4. Store mulch and other bulk supplies away from stream course. If a staging area is required for material handling, the adjacent roads or open grassed ravine area south of Glen Manor Drive should be used. 5. Install sediment control barriers between stockpiles of materials and the stream course or other drainage features. 6. Avoid the use of pesticides and herbicides in the maintenance of restoration plantings where possible. 7. Harvest leaf litter from open space areas to augment soils and mulch planting areas. If supplemented, do not use leaf compost sourced from outside the ravine unless it is tested and confirmed to be free of contaminants and has been completely processed. 8. Erect temporary or permanent barrier fencing to limit use of areas which are exhibiting degradation from over use. Promptly repair fencing and trail barriers to protect regeneration areas from trampling. 9. Actively enforce code of conduct with respect to: i.
Encroachment on restoration plantings
ii. Requirements for permits for school activities and recreational events iii. Littering/ dumping iv. Vandalism v. Excrement deposits vi. Dogs onleash bylaw 10. Temporarily cordon off areas to be revegetated with snow fencing and maintain the fencing until plant establishment. 11.Remove undesirable species from restoration planting areas to mitigate colonization and reduce competition.
1..12.2 Monitorrin ng In es nitiative Monitoring activities should be initiated at the same time as management prescriptions are being implemented. The Management Plan sets out recommendations to monitor the following: •
The stability of slopes and erosion prone areas;
•
The integrity and stability of structures;
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•
Access and trail use/ further ad hoc trail creation;
•
The condition of amenities;
•
The effectiveness of trail closure barriers and signage provided;
•
The successful establishment of restoration plantings;
•
The recovery of restored drainage features and stabilized creekbanks; and
•
The health of vegetation communities in general and specifically, existing mature trees.
The following recommendations are provided to guide the implementation of a monitoring program for Glen Stewart Ravine. 1. Monitoring sites should be identified at strategic locations which should include known problem areas such as seepage sites or eroded areas. These sites should be visible, and if possible, easily accessible in order to extend the program to school/user groups. Monitoring sites should coincide with educational signage to help illustrate the natural processes and interventionist principles applied to restore the site. 2. Monitoring sites should be located on a map visible at each access point to the ravine. 3. The monitoring program requires a commitment of funding and participation over several years to ensure the sustainability of the program in the longterm 4. Findings of the monitoring program should be reviewed and trends in the evolution of the ecosystem noted. This information should then be used to direct the implementation of management initiatives over time. 5. The following areas should be monitored on an annual basis to note any changes in conditions. A report should be made on these changes to help track the progress of recovering sites and overall health of the forest and seepage/wetland ecosystems. Tracking these changes will help ensure the strategies employed are succeeding, and that objectives are being achieved in the shortterm and longterm 1..12.3 Trracking a rtin ng and Repor A sample checklist is provided in the Management Plan Technical Report (section 11.3.2.7) to guide the implementation of actions (prescriptions) and allow
42 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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for the tracking of the progress made toward implementing the recommended prescriptions. Short, medium and long term management prescriptions should be incorporated into this chart and identified by reference numbers that correspond to those listed in Tables 15. 1..13
Role es and Respon p nsibilitties
The implementation of the Management Plan will require the coordinated effort of a number of partners as well as commitment to long term participation. The Management Plan identifies the roles and responsibilities of the following: •
Toronto and Region Conservation Authority
•
City of Toronto Parks, Forestry and Recreation -
Parks
-
Urban Forestry
-
Ravine and Natural Feature Protection
-
Natural Resources
-
Natural Environment and Community Programs
•
Community Involvement
•
Dog Walking Groups
•
Wildlife Groups
1..13.1 Citty off Toronto The following provides a summary of the specific responsibilities of the City in implementing the Management Plan. •
Providing adequate funding to facilitate the implementation of recommended trail and ecological management plan prescriptions, management recommendations, and monitoring programs,
•
Coordinating and overseeing the implementation of capital improvements and management and monitoring initiatives,
•
Ensuring initiatives are implemented with in conformity with the Ravine Bylaw and exerting influence over the Bylaw to ensure initiatives are met,
•
Integrating with park management on City lands in the south part of the ravine,
43 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
•
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Regulating activities within the ravine, including organized community/ school events and activities which require a permit to ensure that the levels and frequency of use does not impede restoration efforts;
•
Enforcing municipal bylaws including offleash regulations, encroachment bylaws, and legislation related to the regulation of activities within the par;
•
Overseeing the coordination of trail construction and improvements, in concert with the management initiatives and priorities,
•
Ensuring that maintenance practices are undertaken in accordance with the recommendations of the Management Plan,
•
Coordinating the design and installation of signage recommendations and park amenities, ensuring City design standards are met, and
• Identifying and capitalizing on opportunities to draw funding from the private sector and local businesses through funding raising and partnerships. Citty Forestry De epartme ent a Forestry staff will be responsible for: •
Monitoring tree health;
•
Identifying and managing tree related issues; and
•
Assisting in the implementation, maintenance and monitoring of restoration plantings.
Na aturall Environmen nt and Communi ity Program g ms Depart p tment This department within the City is well positioned to address the following activities: •
Coordinating planting and clean up events with groups from neighbouring schools such as Glen Ames School;
•
Ensuring that activities initiated by community groups within the ravine are appreciated and consistent with the objectives of the Management Plan;
•
Coordinating and focusing the activities of community interest groups; and
• Enhancing awareness of the community of the sensitivity of Glen Stewart Ravine in an effort to encourage stewardship of the natural environment. 1..13.2 TR RCA •
Monitoring the aquatic stability and water quality of Ames Creek
44 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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•
Regulation/permits and approvals
•
Technical review
•
Potential to assist City staff in constructing some trail, habitat and interpretive initiatives within the ravine
1.13.3 Community/ Vo Volunteer Involvement The potential volunteerism and energy from school students, interest groups and the wider community can be capitalized upon to assist in implementing the recommendations of the Plan. However, it is important that the activities of volunteer groups be conducted under the direction of the City and/or TRCA to ensure that activities are complementary and that efforts are not duplicated. As well, it is also essential that activities undertaken by volunteer organizations are consistent with the goals, objectives, recommendations and priorities set out in the Management Plan. Initiatives appropriate for implementation by volunteer forces, could include: •
The implementation of restoration plantings, particularly shrub and wildflower plantings in dry areas where gradients are not steep;
•
The implementation of initiatives aimed at enhancing habitat including the construction and installation of birdhouses, denning structures, bat boxes, brush piles etc;
•
Assisting in ensuring trail barriers are maintained intact and that closed trails are respected;
•
Maintenance in terms of the collection of litter throughout the park and reporting on damaged amenities and vandalism; and
•
Maintenance of restoration plantings including weeding and watering.
Dog Walki ing Gr roups
Dog walkers should assist in regulating leashed dog walking in the ravine, encouraging others who do not abide by the bylaw to do so. Willdlife s l Groups Groups that have a common interest in nature such as bird watching groups can be a valuable resource and should be encouraged to become involved with the
45 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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monitoring of wildlife in the ravine and education of other ravine users related to the value of the ravine environment. 1..14
Fundin nitie e s d ng Op pporrtun
The implementation of the Management Plan will require additional funding over the longterm and the commitment of private donors and community groups to help realize these funds. There is the potential that the costs of implementing initiatives could be partially offset by: •
Corporate contributions;
•
Forming partnerships with private sector groups;
•
Approaching foundations that provide funds for environmental projects including TD Canada Trust’s – Friends of the Environment Foundation and the Shell Canada Foundation. Environment Canada; and
•
The Ministry of Natural Resources Community Wildlife Improvement Program
Particular avenues of fundraising may include: •
Local landscape suppliers or nurseries for voluntary donations of construction materials and/or plant stock in exchange for the promotion of their name and image in association with the Glen Stewart Ravine project;
•
Private sector companies looking to improve their image by associating themselves with environmental values and/or education in exchange for free ad campaigns on signage or amenities;
•
Seeking other generous benefactors to strengthen ownership and stewardship within the corporate community;
•
Fundraising for trails achieved through donor recognition programs. This model could be successfully adopted to fund components of the Glen Stewart Ravine trail system, the installation of benches and furnishings and the construction of new park amenities;
•
City of Toronto Tree Advocacy Program could be relied upon to assist in implementing the planting strategies set out in the Management Plan; and
•
The City could also investigate the potential to organize a Trees Across Toronto citywide planting event to be held at Glen Stewart Ravine.
46 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre
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The implementation of the Glen Stewart Management Plan is likely to take a number of years requiring that funding and partnership programs will need to be conceived with a commitment to achieving sustained funding levels over the longterm. 1..15
Conclu usion i
The Glen Stewart Management Plan is a comprehensive document which is comprised of an Executive Summary, Technical Report and Appendices. Together the Management Plan documents will be used by the City of Toronto as a guide in allocating funds and implementing priority prescriptions each implementation
cycle.
The
Management
Plan
provides
management
prescriptions in response to issues that were identified through the inventory and assessment phase of the process and relies on the development of a maintenance and monitoring program to ensure the successful implementation of prescriptions and the ecological sustainability of the natural heritage system. The Management Plan has been designed to provide guidance to the City for the next 20 years to manage the natural heritage resources of and use within the ravine in a responsible and adaptive manner. In this way the recommendations will remain relevant over time as the ravine landscape evolves and the maintenance needs evolve.
47 Schollen & Company Inc. ~ North South Environmental ~ LURA Consulting Urban Forest Innovations. ~ Brown and Co. Engineers ~ Geoterre