May 25, 1999

To:Toronto Community Council

From:Commissioner of Urban Planning and Development Services

Subject:Rezoning of the lands within and abutting the Nordheimer Ravine and currently covered by Interim Control By-law 318-1998 (Ward 23 - Midtown)

Purpose:

This report recommends that the lands in and within 10 metres of the Nordheimer Ravine be subject to a restrictive exception which would implement a "Ravine Impact Area". The line defining the "Ravine Impact Area" would be consistent with the current line defining the boundary of the Nordheimer Ravine. Such a regulation would:

(i)be consistent with the environmental policies of the Official Plan;

(ii)be complementary to the Toronto and Region Conservation Authority's fill and top-of-bank regulations;

(iii)have appropriate regard for the relevant policies of the Provincial Policy Statement regarding significant valley lands; and

(iv)be consistent with the policies enacted for the lands generally abutting the Park Drive Ravine.

This report is based on the findings of the study approved by Council of the former City of Toronto pertaining to the Park Drive Ravine which found that privately held ravine lands can contribute to the sustainability and diversity of the ravine as long as an appropriate mechanism is in place to regulate the position of buildings and related development on any given lot. The adoption of the recommended regulations will ensure that such a mechanism is in place respecting the lands abutting the entire Nordheimer Ravine.

Financial Implications:

There are no requirements for any municipal expenditure associated with this approval.

Recommendations:

It is recommended that:

1.City Council amend Section 12(2) RESTRICTIVE EXCEPTIONS of the Zoning By-law 438-86, as amended, for the former City of Toronto by:

(a) adding a "Ravine Impact Area" and stating that no person shall, on a lot which is located wholly or partially within 10 metres of the Ravine Impact Area of the Nordheimer Ravine, or within the Nordheimer Ravine, use or erect a building, structure or an addition for any purpose, other than those required for flood and/or erosion protection or those related to federal, provincial or municipal infrastructure, unless the building, structure or addition is set back 10 metres from the Ravine Impact Area, except that:

(i)an addition can be made to a building or structure existing at the time of the passing of this by-law that is within 10 metres of the Ravine Impact Area, provided the proposed addition is no closer to the Ravine than any existing wall of the existing building or structure; and

(ii)any building or structure existing within 10 metres of the Ravine Impact Area at the time of the passing of this by-law may be replaced, provided that the replacement building or structure does not have any greater floor area or height and is in the same position relative to the lot lines as the building or structure it replaces; and

2.the City Solicitor be authorized to prepare and submit to Council the necessary by-laws.

Council Reference/Background/History:

In accordance with the recommendations of Clause 7 of the Land Use Committee Report 10, adopted by Council of the former City of Toronto on July 14, 1997, I was requested to report back on a process and timetable for developing "Ravine Impact Boundaries" for ravine areas throughout the former City of Toronto. In this Department's report, also of July 14, 1997, respecting the Nordheimer Ravine, I advised that I would begin the requested study by reviewing the issues pertaining to the lands abutting the Nordheimer Ravine. At that time, it was also stated that the study would be limited initially to this ravine due to the constraints of staff resources and the priorities related to questions associated with the relationship of the top-of-bank to the defined ravine limit and known development activity within this area, particularly the then proposed construction of four houses on Glen Edyth Drive.

On July 14, 1997, the Council for the former City of Toronto adopted By-law No. 1997-0371 (see Map 1) which had the effect of prohibiting for a period of one year, the erection of any building or structure within 10 metres of the Nordheimer Ravine. Subsequently, at its meeting on June 3 and 4, 1998, Council of the City of Toronto adopted By-law No. 318-1998 which served to extend the Interim Control By-law applying to these lands for a further period of one year.

Comments:

1. Location

The ravine is generally located to the southeast of the intersection of St. Clair Avenue West and Bathurst Street and runs to the southeast almost to Davenport Road at Poplar Plains Road.

2.Planning Considerations

2.1Background

City Council of the former City of Toronto adopted the Interim Control By-law for the Nordheimer Ravine (By-law 1997-0371) at the same meeting as it adopted the amendments to By-law 438-86 imposing a Ravine Impact Boundary (or Area) for the lands abutting the Park Drive Ravine. The amendments to By-law 438-86 for the Park Drive Ravine imposed restrictions on the use and development of the lands generally within the first 10 metres from the boundary of the Park Drive Ravine and within the ravine. Subsequent appeals pertaining to two specific properties which were also dealt with in this report continue to be the subject of ongoing appeals involving the City and the property owners. However, it should be noted that the By-law was approved by the Ontario Municipal Board as it applied to the balance of the approximately 170 properties affected by this change to the By-law.

At the time of the passing of the Interim Control By-law for the lands abutting the Nordheimer Ravine, I noted in my report that there were active building permit applications to allow the construction of 4 new homes on lots now known as Nos. 11, 15, 17, and 19 Glen Edyth Drive. Three of these new houses have now been completed on lands immediately abutting the ravine. The construction of these houses has resulted in significant negative impact on the slopes and vegetation abutting the ravine. The proposed revisions to the Zoning By-law would have restricted the issuance of building permits for the construction of these houses had the amendments been in place prior to the applications for these building permits.

2.2Character of the Ravine

Toronto's ravines are one of the most significant physical features of the City and were important in determining the structure of the City. They continue to play an important role within the City as part of the ecosystem, as a major feature of the drainage system within the City and as areas of natural amenity and recreation. During the development of the City, roads generally bypassed the ravines, streams were allowed to continue to run through them and development generally was not undertaken within the ravines. Today, however, quality urban land is scarce and due to their amenity, lots abutting or within the ravines are highly marketable for residential development. These characteristics, coupled with current engineering techniques which can overcome many of the physical constraints to building on, or adjacent to, steep slopes, make the ravines more vulnerable to development.

The Nordheimer Ravine terminates at its southern end at the former shoreline of glacial Lake Iroquois. Consequently, the steepness of the ravine slopes diminishes towards the Davenport Road end of the ravine and there is significant residential development in this area. The original streambed within the ravine has long been buried and is no longer visible as it traverses eastwards towards what is now known as the Rosedale Valley Ravine and into the Don River. More recently, the natural water seepage from the ravine slopes has been captured in two wetland areas. A program also has been undertaken by the City to introduce and protect existing native vegetation within these wetland areas and on the abutting slopes.

The vegetation of the ravines plays an important role in absorbing carbon dioxide and improving air quality. In addition, the vegetation within the ravines absorbs significant amounts of urban noise, giving the surrounding areas a sense of calm and quietness. This is especially evident at the bottom of the ravines where steep ravine walls create a natural barrier to urban sounds. This noise buffering capability is eroded as development encroaches into the ravines and development starts to generate its own sounds.

In general, it is estimated that while the majority of the plant species documented in the Nordheimer Ravine are native to the area, there are significant intrusions of Manitoba maple, Norway maple, Siberian elm and other non-native species which tend to reduce the biodiversity and the richness of the overall species mix. A large portion of the ravine bottom has been cleared over the years as a result of various construction activities, including the construction of the TTC subway. However, as further development encroaches into the ravine, there is greater potential for slope failure, erosion of topsoils, the introduction of retaining walls and the replacement of native species with invasive species. The loss of natural vegetation in the ravine also has a significant negative impact on wildlife habitat.

2.3Erosion Control and Protection at the Top-of-Bank

The encroachment of development close to the top-of-bank has historically led to problems with erosion. The causes of such erosion can be traced to increased runoff, dumping of garden refuse on the ravine slopes with the resulting destruction of existing vegetation, and increased pedestrian traffic on the ravine slopes. As well, some erosion occurs around the bases of bridges and along retaining walls built to extend rear yards abutting the ravine.

If this area were being subdivided today (rather than in the early part of the 1900's), in accordance with principles of sound ecological planning and best management practices, it would be likely that development would not be permitted so close to the top-of-bank, nor would the lower areas of Russell Hill Road or Glen Edyth Drive have been allowed to encroach into the original landform of the ravine. More likely, a buffer zone would have been required that would provide effective protection of the forest edge from the effects of wind and sun exposure, as well as to protect against undue loading of the top-of- bank and diversion of ground water. Due to the age of the development in the area, however, this level of protection and stewardship has not generally been practised. This has left this ravine subject to considerable urban stress similar to many other ravines within the City.

2.4 Urban Structure

The Nordheimer Ravine plays a significant role in the network of ravines within the City and is the southerly extension of the Cedarvale Ravine running north from Tichester Road. It was also originally connected to the Park Drive Ravine to the southeast, but the natural character of this connection has been lost due to landfill and the development of the city. However, the ravine remains an important natural open space and landscape within the urban environment and significantly adds to the quality of urban life.

The ravine also provides a significant recreational resource for jogging, walking, cycling, tobogganing and other passive recreational activities. In most cases, the existing residential dwellings on top of the ravine slopes are set back a reasonable distance and masked by substantial vegetation. Such setbacks help to ensure that the scenic quality of the ravine is maintained, as well as the stability of the ravine slopes.

The Official Plan addresses the issues of managing and preserving our natural heritage and ravine resources. As these resources are limited within the context of urban life and vulnerable, it is appropriate that land management practices and responsible land stewardship should be practised systematically to sustain the ravine system for future generations.

2.5 Current Processes for Regulating Development

Development regulation is the primary function of the General Zoning By-law 438-86 and other site-specific by-laws. These by-laws serve to implement the policies of the Official Plan. Development within any defined ravine area is also subject to Ravine Control (as defined in Chapter 276. Ravines of the former City of Toronto's Municipal Code) and Site Plan Approval.

These regulatory mechanisms are generally legislated through the Planning Act and the City of Toronto Act which gives the City certain additional legislative authority to regulate specific matters not defined within the Planning Act. Ravine preservation is one such matter. The Municipal Code consolidates many of the specific by-laws/processes which may affect an application for development. Other relevant policies are contained in the Toronto and Region Conservation Authority policies, the former Metropolitan Toronto Official Plan and in the Provincial Policy Statement.

(a)Provincial Policy Statement

The Provincial Policy Statement came into effect on May 22, 1996. Ravines are not specifically defined in the Provincial Policy Statement, but significant valley lands are classified as Natural Heritage features.

The Provincial Policy Statement (Policy 2.3) recognizes all valley lands within the area including Toronto as significant, as they may constitute the only remaining natural areas in the municipality. As such, these valley lands can form the basis for a natural heritage system within the planning area. The Provincial Policy Statement also suggests the provision of a 50 metre buffer for significant valley lands. The 10 metre buffer recommended by this report is a compromise between that recommended in the Provincial Policy Statement and the current reality of no required buffer.

(b)Metropolitan Toronto Official Plan

The Nordheimer Ravine is within the Metropolitan Green Space System identified in the former Metropolitan Toronto's Official Plan (Metroplan). The objective of designating the Metropolitan Green Space System in Metroplan is to plan and manage this system and abutting lands in a way that protects and rehabilitates the integrity of the natural features and ecological functions, improves physical connections to other green spaces, meets recreational and leisure needs of the Toronto population, and enhances the form of the City.

The policies in Metroplan seek to achieve the Metropolitan Green Space System through, among other things, participation in initiatives for the protection and regeneration of significant natural areas. Significant natural areas include, but are not limited to, sensitive and ecologically fragile areas and aquatic systems, and terrestrial habitats, as identified by the Province, the TRCA and/or a Municipality. Such areas may include: ravines, wetlands, wood lots, environmentally significant areas, areas of natural and scientific interest, valley land impact zones, environmental impact zones and waterfront impact zones.

The policies in Metroplan also state that no new buildings or structures, other than replacements, minor extensions or accessory structures are to be permitted within ravines or within a minimum of 10 metres from the edge of significant natural areas, where these extend beyond the ravine slopes; except where the Area Municipality is satisfied, after consulting with Metro and the TRCA, that the proposal does not detract from the objectives of the Plan and is in accordance with policies in Metroplan.

(c)City of Toronto Official Plan

The current policies of the Official Plan respecting Ravines and Open Space areas have evolved over a long period of time. Starting in 1960 with the Natural Parklands report, policies respecting the preservation of open space and the ravine systems have increasingly provided greater protection for the preservation of the natural environment. In 1983, Council of the former City of Toronto adopted Official Plan Amendment 228 by By-law 344-83, designating the lands within the Nordheimer Ravine as a Ravine. The delineation of the boundaries of the ravine were incorporated in Appendix 'A' (Ravine Maps) of the Plan.

The current Official Plan (Cityplan) for the former City of Toronto modified the previous Open space designation by splitting it into three classifications - Open Space, Natural Areas and Environmentally Significant Areas. The Nordheimer Ravine is designated as a Natural Area and Ravine. Policies with respect to Ravines and Natural Areas are found in Section 2 of the Plan, while Parks and Open Space policies are located in Section 4.

The policies generally stated throughout Section 2.3 of the Plan direct Council to protect and enhance Natural Areas, Environmentally Significant Areas, Ravines and the natural Lake Ontario shoreline. Section 2.4 of the Plan further deals with issues pertaining to development in and abutting ravines and sets criteria for review if development is proposed within the ravine areas. More specifically Section 2.48 of the plan recognizes that development adjacent to ravines has potential for significant impact upon the ravines and encourages the establishment of "a buffer zone at least 10 metres adjacent to the Ravine, Natural Area or Environmentally Significant Area within which all development is to be discouraged, and where 10 metres is clearly impractical, provide as large a setback from the boundary of the Ravine, Natural Area or Environmentally Significant Area as is possible". Section 2.54 also addresses the issue of slope stability as it affects the safety of built structures and their occupants. These sections of the Plan suggest that Council should address the issues of the protection and enhancement of these areas and that a buffer zone adjacent to the ravines should be enacted.

(d)The former City of Toronto's Zoning By-law (438-86, as amended)

The general Zoning By-law sets regulations for the development of land including: permitted uses, maximum lot coverage density, minimum lot frontages, setbacks, height, and the requirements for open space and parking, among other matters. The first comprehensive by-law for the former City of Toronto was enacted in 1952, well before the City introduced protective measures for the Nordheimer Ravine (1983), and substantially after most of the current development abutting the ravine.

The authority for the enactment of the Zoning By-law is derived from the Provincial Planning Act. This Act allows municipalities to regulate the use of land and set standards for most forms of development. As such, the Zoning By-law can be used to ensure that development is set back from the designated Ravine. At the present time, however, there are no specific regulations in the General Zoning By-law restricting development within ravines. With the exception of the lands within and abutting the Park Drive Ravine, the process of regulating development within ravines has only been undertaken by way of the designation of the Ravines within the Official Plan and with the corresponding regulations found in the former City of Toronto Municipal Code.

(e)City of Toronto Act and Ravine Control By-law

In 1971, The City of Toronto Act was enacted giving the City legislative powers to regulate ravine preservation by way of by-laws. The City enacted its first Ravine Control By-law in 1981. It was not until 1983, however, that it enacted By-law 344-83, designating the Nordheimer Ravine limits.

In 1994, the City of Toronto passed By-law 1994-0751, which incorporated the Ravine Control By-law into the City's Municipal Code, under Chapter 276. The Code currently requires Council consent for any development, change of grade or removal of vegetation within Ravines and also defines certain exemptions. Lands which are subject to the Ravine Control process are only those lands wholly located within the ravine boundaries as identified in Chapter 276.

In situations where consent of Council is required under Chapter 276 of the Code, an application is filed with Urban Planning and Development Services and distributed to other civic departments for comment. Once a satisfactory proposal is achieved, the recommendations included within a staff report are presented to the Toronto Community Council and City Council for approval. If approved, the City Solicitor is usually directed to prepare a Ravine Control Agreement.

(f)Site Plan Control

Pursuant to Chapter 165, Article III of the Municipal Code, the proponent of any development within a designated ravine is required to obtain Site Plan Approval prior to being able to obtain a building permit. This requirement allows the City to fully regulate all details of the development and to ensure that appropriate landscaping is undertaken, including all aspects related to grading, drainage and the definition of suitable plant material.

(g)Toronto and Region Conservation Authority

In addition to the municipal approval process, there are two regulations that the Toronto and Region Conservation Authority (TRCA) applies to development proposals within and adjacent to ravines. The first regulation is Ontario Regulation 158 under the Conservation Authority Act which regulates the following:

(i)placement of fill within Fill Regulated Areas;

(ii)the building or renovation of structures within a flood plain; and

(iii)the alteration of a watercourse.

Most lands that back onto a ravine are considered by the TRCA to be within a Fill Regulated Area under Ontario Regulation 158. The TRCA must approve by permit any placing of fill, construction of any sort (e.g. swimming pool, greenhouse, fencing, etc.), renovation, addition or alteration to an existing building and alteration to a watercourse. The intent of the Regulation is to prevent development that could lead to damage by floods or erosion and to protect the public.

The second regulation is the TRCA's Valley and Stream Corridor Management Program (VSCMP) which was put in place in 1994. The TRCA's VSCMP governs the way development is to occur within ravines and aims to protect and rehabilitate ravine corridor landforms, features and functions while being sensitive to development opportunities. The intent of the Authority's VSCMP is to prevent new development that would introduce risk to life and property associated with flooding, erosion and slope stability and/or is not compatible with the protection and rehabilitation of surrounding natural features and functions. In order to afford some protection to a ravine, the TRCA prescribes a minimum 10 metre setback from the stable or predicted long-term stable top-of-bank.

2.6Effectiveness of Current Land Use Regulations

The focus of this report has been to review the currently available regulatory tools to determine their ability to deal with proposed development within and abutting ravine areas.

From a planning perspective, Toronto's ravines are a fundamental feature of the City's infrastructure and a significant determinant in the form of the development within the City. They also represent a resource and an amenity which cannot be recreated or replaced. Accordingly, it is appropriate that the Nordheimer Ravine be protected through the implementation of a buffer zone adjacent to the designated ravine to ensure the stability of the ravine edge and the maintenance of a naturally vegetated area adjacent to the ravine.

With the exception of the Park Drive Ravine, at present the General Zoning By-law does not implement the policies of the Official Plan to encourage at least a 10 metre setback for development proposals adjacent to the Nordheimer Ravine, or as large a setback as possible where a 10 m setback is impractical. This is a "regulatory gap" in the By-law, given the intent of the Official Plan to preserve and enhance the ravine system.

2.7Development Adjacent to the Nordheimer Ravine

The majority of the 92 properties abutting the Nordheimer Ravine are developed with residential buildings within the relatively flat tableland portion of the site and with varying amounts of their rear yards reaching into the ravine slope (see Map 2). This tableland has provided a suitable area for building, while the sloped rear yards have provided a desirable, wooded slope providing significant privacy. This has resulted in a pattern of low density development which respects the natural characteristics of the ravine. Buildings have generally been placed well above any areas of significant slope to ensure slope stability and also to ensure that the scenic value of the ravine is not compromised by development perched on the edge of the ravine. In certain recent instances, however, the pressures of new development have pushed the limit of this traditional pattern of development with the construction of new homes and accessory uses verging at the edge of the ravine slopes, the cutting of existing vegetation and by creating obtrusive and highly visible features from within the ravine. In some instances in other ravines, development close to the ravine edge has caused increased erosion and even failure of the ravine slope.

Restricting development within ravines and establishing a development buffer adjacent to environmentally sensitive areas, such as ravines, is a recognized planning practice in many municipalities. This report recommends that the setback be a minimum of 10 metres, consistent with Section 2.48(c) of the Official Plan and the practice of the TRCA in its Valley and Stream Corridor Management Program. The 10 metre setback is also appropriate from a scenic and visual analysis perspective in that it ensures that most house-form, residential buildings will be set back sufficiently so that the majority of their bulk will not be visible from within the ravine. Obviously, local circumstances, such as ravine slopes and other factors including the density of vegetative cover, determine how much of a building can be seen.

3.Conclusions:

Having regard for the City's Official Plan policies respecting the protection of the ravine system, this report concludes that the City's Zoning By-law needs to be amended to:

-provide greater protection of the natural heritage features of the Nordheimer Ravine;

-maintain its visual and scenic characteristics; and

-minimize the hazardous impact that development may have on the stability of ravine slopes.

It is recommended that the Zoning By-law be amended to indicate those areas of land within and abutting the Nordheimer Ravine where residential development is not permitted. Specifically, it is recommended that the former City of Toronto's General Zoning By-law (Section 12 (2)) be amended to identify a "Ravine Impact Area" for the Nordheimer Ravine and to require that all new development be set back not less than 10 metres from the currently designated Ravine. This 10 metre setback should help to ensure that there is an appropriate physical relationship between new residential development and the designated ravine. The line defining the "Ravine Impact Area" would be consistent with the current line defining the boundary of the Nordheimer Ravine.

So as not to unreasonably impact existing development, which in many cases was constructed prior to the evolution of environmental policy through the 1960's, it is recommended that an exception be provided in the Zoning By-law amendment for existing buildings which are currently closer to the top-of-bank than the minimum 10 metre setback recommended. For example, if a building currently is only 5 metres from the defined Ravine, it is recommended that additions be permitted to that building so long as the addition is no closer to the Ravine than the original building. The addition would have to comply with all other applicable laws.

It should also be noted that the original Ravine boundary was defined based on the best information available about the actual top-of-bank, having appropriate regard for the presence of existing buildings and other changes made to the Ravine over time. The line was plotted and dimensioned to be placed in the Zoning By-law. However, it is clear that the line is an approximate representation of the actual top-of-bank. Accordingly, there may be circumstances where it is appropriate to vary the line based on the findings of environmental analysis and survey. For example, if a property owner can demonstrate by way of a physical survey, vegetation analysis and restoration plan, as well as an accompanying soils analysis that the outside boundary of the Ravine Impact Area is actually farther away from the top-of-bank than defined in the Zoning By-law, then it would be appropriate to grant a variance from the line to allow development to proceed. Such variances should only be granted after careful study and assessment, including corroborating documentation.

Because the exceptions provided for in the proposed By-law amendment relate to existing development and additions, this amendment should not have a significant negative impact on maintaining or adding to existing residential buildings. Non-exempt structures proposed inside the ravine would require consent, site plan approval and variances/rezoning. Non-exempt development within 10 metres would require variances/rezoning. Again, such approvals should only be granted after careful study and assessment. Over time, as buildings are redeveloped, the required 10 metre setback will ensure that all new development is appropriately set back and will create a more sustainable form of development adjacent to the ravine edge.

Contact Name:Angus Cranston

Telephone: (416) 392-4025

Fax: (416) 392-1330

E-Mail: acransto@toronto.ca

Beate Bowron

Director, Community Planning, South District

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