About Midtown ravines
Two significant ravines extend from Mt. Pleasant Cemetery and south to the Don Valley: the Yellow Creek ravine just east of Yonge Street and the Mud Creek ravine to the east of Moore Park. A third major ravine runs from Ramsden Park down Rosedale Valley Road to the Bayview extension in the Don Valley.
A smaller midtown ravine – Cudmore Creek — – runs beside Bayview Avenue near Crothers Wood, emptying in the Don near the Pottery Road bridge. All creeks in midtown ravines are tributaries of the Don River.
The ravines were originally formed by melting glaciers. The ravine system began to take shape approximately 12,000 years ago at the end of the Last Glacial Period, when the glaciers that once covered Toronto retreated. As the kilometre-thick ice melted over the space of several thousand years, the huge volume of water gradually carved out the valleys and rivers that eventually formed deep ravines.
The glaciers originally drained into a lake — Lake Iroquois — that was much larger than Lake Ontario because a thicker glacier to the east blocked drainage through what later became the St Lawrence River. Until that thicker glacier also melted, Lake Iroquois drained into the Atlantic through the Hudson River.
Midtown Toronto’s ravines, including those carved by Yellow Creek and Mud Creek, have been part of an Indigenous cultural landscape for thousands of years. The first occupants were nomadic hunter-gatherers who arrived 10,000 to 11,000 years ago as the glaciers melted.
By the 14th century, Wendat and Haudenosaunee peoples lived in the region, and in the 17th century, the Mississaugas of the Credit First Nation became the dominant Indigenous group. While no major evidence of settlements has been found in the midtown ravines, archaeological surveys in adjacent areas of the Don Valley have uncovered Indigenous artifacts.
French explorers arrived in the 17th century, followed by British colonists in the 18th century. The British established the Town of York (later Toronto) in 1793, initially populated by British settlers fleeing the American revolution.
The Yellow Creek and Mud Creek contained rich deposits of red and yellow clay, originally deposited in the lakebed of Lake Iroquois. This clay was ideal for brickmaking, and major brickworks were established in the areas such as Ramsden Park and the Don Valley.
Brickmaking at the smaller brickworks was relatively short-lived, declining by the 1880s due to increasing residential development along with competition from larger brickworks in Milton and the Don Valley Brickyards (now a major urban park and community center, the Evergreen Brickworks). The Don Valley Brickyards continued to operate until 1984.
The ravines were carved by water and that continues with every rainstorm. Their sandy, silty and clay-rich soils are prone to erosion, especially when vegetation is disturbed. Urbanization, and climate change have only accelerated this natural process.
Thanks to climate change (human-induced global warming), summertime water temperatures in the Gulf of Mexico and the Caribbean can reach over 30 degrees Celsius, causing much-increased evaporation, worse hurricanes, and water-saturated atmospheres over Eastern North America. The result is much more frequent extreme weather events over Toronto, further exacerbating the erosion.
The loss of native vegetation that held soil in place has also played a significant role. Invasive species such as Norway maple create dense shade and prevent undergrowth, leaving soil bare and vulnerable. Garlic mustard and other invasives spread aggressively, displacing native species and altering soil chemistry so that natives won’t grow.
And we have made this worse by paving over farmland. Back in 1900, most land north of St Clair Avenue was farmland that absorbed a considerable portion of most downpours. Now, most of the area draining into the midtown ravines is paved over, draining quickly into the storm sewers that empty into midtown ravines.
About the Midtown Ravines Group
The MRG began in 2016 as an informal cooperative effort of several midtown residents’ associations (Summerhill, North and South Rosedale, and Moore Park). The group was initially formed to lobby City Council to address the deplorable state of the Vale of Avoca (Yellow Creek) ravine. Our lobbying included presentations to Council committees, supporting the City’s emerging Ravine Strategy and advocating for the establishment of a Vale of Avoca Working Group.
The group quickly expanded to include the Deer Park Residents Group and subsequently the Governors Bridge Residents Association and later grew to include the ABC Residents Association and South Eglinton Davisville RA as well as the Bloor East Neighbourhood Association and a new RA set up by Avoca Vale.
It was incorporated as a non-profit organization in September 2019 to serve as a financial conduit for donations to improve the state of the Midtown Toronto ravines. The first use of this conduit was to invest a grant from Toronto Hydro in funding a pollinator garden at Rose Avenue Public School. Currently, the group’s websites and other outreach are funded primarily by grants from its member RAs.
We work in cooperation with Toronto Nature Stewards to foster citizen participation in stewardship activities. The scope for this is limited by what City staff permits. We are seeking to expand this scope, which currently (and surprisingly) does not include the ecologically sensitive ravine areas that are most in need of stewardship.
For an excellent review of what is required and how the ecological challenge has increased, see the 2017 submission to a City committee by the Toronto Ravine Revitalization Study (https://www.toronto.ca/legdocs/mmis/2017/ex/comm/communicationfile-72084.pdf). That report summarizes a privately funded 40-year research study by the University of Toronto Faculty of Forestry of the evolving ecological state of the Park Drive Reservation component of the Yellow Creek ravine.
Enhancing the ecological integrity of the Yellow Creek ravine is a major component of the MRG’s Community Vision for the Vale of Avoca ravine.
Through cleanup efforts and other activities to help maintain the ravines.
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If you’re willing to help, please volunteer. We need and welcome all the help we can get.
We are currently applying to the Canada Revenue Agency for recognition as a charitable agency so that we can issue tax-creditable donation receipts.
What else does the MRG do to connect with the community?
We organize walks and talks, promoting awareness of what is happening in our ravines. We also reach out to members of participating RAs at AGMs and other meetings, as well as through our website and other social media.
The Vale of Avoca Master Plan
As a result of our lobbying in 2015 and 2016, our local City Councillors — then Krystyn Wong-Tam and Josh Matlow — formally requested the formation of a joint City/citizen working group in 2016. City staff reported on the request in October 2017 after the City’s Ravine Strategy was made public. City Council formally established the working group in February 2018.
The key purpose of the working group was to develop an interdepartmental Master Plan for the restoration of the Yellow Creek/Vale of Avoca ravine, overcoming the silo-based planning by City divisions (Parks, Toronto Water, and the TRCA), each of which is responsible for different aspects of what needs to be done in the ravine. The Midtown Ravines Group has been an active participant in the working group, along with staff from each of the public agencies, since it was set up.
Good question!
Back in 2016 and 2017, it was recognized that an engineering survey (a hydrogeomorphic study) needed to be undertaken to recommend how to control the accelerating erosion in the ravine. At that time, the study was expected to be undertaken in 2018 and last three years. Its start was postponed to 2020, and it lasted longer.
A summary of the initial results of the hydrogeomorphic study was finally made available for public review in the fall of 2023, but the full study was not released until February 2025. For details of the study and the MRG response, see https://valeofavoca.ca/2025/05/30/mrg-comments-on-vale-of-avoca-gmsp/. The geomorphic study set out a timetable for Toronto Water investments in the ravine in which its share of erosion control work would not occur before the mid-2030s.
The City set out a timetable for subsequent planning in a report to a City Council committee in June 2023 (see https://www.toronto.ca/legdocs/mmis/2023/ie/bgrd/backgroundfile-237424.pdf). That timetable projected completion of a park trail Master Plan in 2027, with no commitment to funding the required work.
We have decided we cannot wait for the City to act. With the encouragement of our local councillors (Josh Matlow and Dianne Saxe), we chose in 2024 to organize a private/public partnership to galvanize a speedy restoration of the Vale of Avoca ravine. The first result is the Community Vision report published in March 2025, a 10-page document produced by the Midtown Ravines Group board.
We are currently working with the City to accelerate the development of a detailed Master Implementation Plan based on our Vision plan. This plan will include a detailed phasing and costing of the work that will be required. Our aim is to have this plan completed over the next year.
We are also working with the City and the Evergreen Foundation to organize a major fundraising program once the detailed Master Plan is completed.
This is not easily answered. Our first priority is to complete the detailed Master Implementation Plan. We are working with the City to achieve this, hopefully by mid-2026. Once this has been completed, we will begin our fundraising campaign. How quickly we can raise funds will determine how fast work in the ravine can proceed.
The required work will be implemented in phases and will necessarily be spread over several years. Our aim is to schedule the major construction work for winter months as much as possible, so that the ravine remains open to the public in the summer. Please sign up to receive our newsletters so that we can keep you informed.
Other Midtown ravines
Partly in response to requirements of the Evergreen Brickworks, considerable work has been done in the Mud Creek ravine over the past two decades to upgrade drainage and protect against erosion. Two recent projects have recently been completed by the TRCA: a stream erosion control project just north of the CP Rail bridge and an upgraded access ramp from Moore Avenue down into the ravine.
The bottom of the Mud Creek stream is higher than the Brickworks. A major rainstorm, on July 16, 2024, breached the armour-stone-reinforced wall that kept Mud Creek from draining into the Brickworks. Unfortunately, the creek flows through an underground pipe in the section below the switchback down from Chorley Park, and the pipe was not sufficiently large to be able to handle the stormwater flow. As a result, the stream overflowed and undercut the wall. The result — a mass of earth and stones that formerly made up the wall — can still be seen in the Brickworks pond.
Thanks to many years of lobbying by the Bloor East Neighbourhood Association, there is to be a major upgrading of the pedestrian and cycling trail adjacent to the road. This work is expected to start later this year.