May, 2026 - CANUE

Montreal’s Nature-Based & Equity-Oriented Response to Heat

Image source: City of Montreal – Jonathan Bélisle

Text by Kim Perrotta

Montreal’s Climate Change Plan

Adopted in December 2020, Montreal’s Climate Change Plan 2020-2030 was developed with a commitment to making the city greener, fairer, more resilient, and carbon neutral. The plan was designed to meet the city’s new climate target “to reduce its greenhouse gas (GHG) emissions by 55% by 2030” and to enable the Montreal community to reinforce the city’s climate resilience. The 52 measures in the Climate Plan will set Montreal on the path to being a resilient, inclusive and carbon-neutral city.

This plan is consistent with the Montreal strategic Plan, Montreal 2030, which is guided by four key goals:

accelerating the ecological transition;
reinforcing solidarity, equity and inclusion;
amplifying democracy and participation; and
stimulating innovation and creativity.

Nature-Based Goals and Indicators for Climate Resilience

In order to increase resilience to climate hazards such as heat waves, heavy rain, and destructive storms, the climate plan commits the city to “increasing protected natural areas and the resilience of urban forests, reducing heat islands, restoring the riverbanks and favouring the development of healthy and dynamic urban agriculture”.

The plan includes eight indicators that are to be monitored and reported on annually. Four of those are dedicated to the city’s climate adaptation:

“The number of trees planted by the city and its partners with priority given to vulnerable areas to heat waves with the goal of planting 500,000 trees by 2030;
The area of land to be protected as a natural area or natural environments that contribute to biodiversity with the goal of increasing that area to 10%;
The status of climate hazards with the goal to decrease overall vulnerability; and
The area of heat islands with the goal to decrease that area.”

All of these indicators are pertinent to extreme heat and the heat resilience of the City of Montreal, although some have goals related to biodiversity, flooding and other climate-related events.

Nature-Based Interventions: Increasing the Ratio of Greenspace

“The climate plan identifies several nature-based solutions that can increase the heat resiliency of the city,” said Claudia Atomei, Planning Consultant with the Adaptation, Resilience and Biodiversity Division in the Office of Ecological Transition and Resilience with the City of Montreal. “First, Action 17.1 aims to develop the necessary means to curb the use of impermeable artificial surfaces such as pavement and concrete, particularly through urban planning and regulations. Montreal’s Land Use and Mobility Plan aims to increase the ratio of greenspace from 38% at present to 40% by 2050. This will help reduce temperatures while increasing the absorption of water from rain and snow.”

“This may not sound like an ambitious target, but it is when you consider how much development will happen across the city over the next 25 years and the fact that Montreal is situated on an island with hard boundaries for growth,” noted Rachel Mallet, Research Geomatic Analyst on Climate Change Adaptation, in the Adaptation, Resilience and Biodiversity Division with the City of Montreal.

“This action will require mapping the physical properties of surface materials across the Agglomeration of Montreal for their reflectivity and heat storage capacity,” Mallet noted. “We want to map these surfaces so we can evaluate the vulnerability of different neighbourhoods to heat waves and monitor our progress over time.”

“Second, Action 17.2 in the climate plan aims to increase green spaces in vulnerable and priority areas in the city by promoting the removal of pavement and concrete on streets and lots surrounding schools, low-rent housing, and seniors’ residences,” said Mallet.

Nature-Based Interventions: Increasing Tree Canopy within Vulnerable Areas

A third action in the climate plan, Action 20, requires the City and its partners to plant, maintain and protect 500,000 trees in neighbourhoods vulnerable to heat waves between 2020 and 2030. It aims to reduce indoor and outdoor air temperatures to protect people, while also decreasing energy costs, air pollution, noise levels, and the risk of flooding.

The trees are to be planted on public and private property. The City has set aside funds in its Ten-Year Capital Expenditures Program to reach 50% of this target and expects the private sector and senior levels of government to provide the rest.

The trees are to be selected for their climate resilience and with an eye to encouraging biodiversity. Policies are to be developed to prioritize the planting of trees in the neighbourhoods that are most vulnerable to heat waves. The city is supporting the boroughs by identifying potential planting sites, including sites that need to be de-paved, which are very often located in urban heat islands.

Nature-Based Intervention: Other Actions that Increase Heat Resiliency

The climate plan includes several other actions that are directed at increasing biodiversity or flood resiliency that will also improve the city’s heat resiliency:

Action 19 commits the City to increase the proportion of protected natural areas and areas that contribute to biodiversity from 6.1% to 10%. To achieve this goal, the City is creating new parks and green corridors that connect natural spaces. The primary goal of this action is to support wildlife movement and the dispersion of plants but it will also cool neighbourhoods.
Action 19.2 aims to optimize the ecological contribution of municipal green spaces in ways that support biodiversity such as reducing mowing frequency.
Action 21 commits the city to restoring the public riverbanks in the large parks network and will add green and blue spaces in the city that can help reduce air temperatures.

“We are working to naturalize the city’s greenspaces,” said Atomei. “We are promoting the replacement of tightly-trimmed green grass with indigenous mature plants that have deeper roots, absorb more water, and support a more diverse mix of insects, birds, and mammals. This type of vegetation also has a greater cooling effect on air temperatures, especially during night-time.”

“Montreal is also committed to becoming a ‘Sponge City’ that has parks, streets, and boulevards that use vegetation and containment systems to absorb and capture rainfall and snow melt,” offered Atomei. “While these surfaces and structures are designed to manage stormwater, reduce flooding, and improve water quality, they will also help cool air temperatures.”

Assessing Climate-Related Risks and Tracking Progress

The climate plan commits the city to develop a decision-making tool to analyze the land across the Montreal Urban Agglomeration for its vulnerability to climate-related impacts. This analysis, which has been integrated into the 2050 Land Use and Mobility Plan, helps to identify the areas most vulnerable to extreme events. It is also used to monitor progress using the indicators identified above.

“I have been tasked with the job of developing tools that can be used to identify vulnerable neighbourhoods that should be prioritized for action to protect people at greatest risk of harm from climate-related events,” explained Mallet. “The index for greening, for example, is based on data related to urban heat islands, the tree canopy index, areas vulnerable to heat for health reasons such as age, neighbourhoods that are vulnerable to harm for socioeconomic reasons, and living environments where people live or congregate. The Large Parks, Mont Royal, and Sports Department use it, among other things, to adjust their program for creating and enlarging designated areas for planting trees”.

Assessing the Efficacy of Climate Resiliency Measures

The vulnerability index is also used to assess the urban planning policies and interventions that can be used to protect people from extreme events such as heat.

“Our Division is assessing various climate resiliency interventions for their efficacy under different circumstances,” said Mallet. “For extreme heat, this includes the gathering of existing data and the collection of data that is missing such as surface and air temperatures in local areas, to analyse how well various resiliency measures reduce surface and air temperatures, decrease the area of urban heat islands, or reduce the exposure of residents.”

“When it comes to heat, these assessments will likely be directed at interventions that have been employed in the boroughs such as white roof by-laws and green laneways, as well as those that have been employed by other jurisdictions,” added Mallet. “This will be particularly important for priority neighbourhoods where tree planting is not feasible because of space constraints.”

✅ Montreal Governance Structure

The City of Montreal and 15 reconstituted cities are part of the Montreal Urban Agglomeration which provides common services such as water treatment, waste management, and policing for the whole region. The City of Montreal, which is composed of 19 boroughs, has a population of approximately 1.7 million people. The central office in Montreal provides data, policy support, and funding to the boroughs, but the boroughs can and do develop and implement programs and policies independent of the central office.

This project is carried out with funding from the Federation of Canadian Municipalities’ Green Municipal Fund
and the Government of Canada.

Sponge parks in Montreal

Image source: City of Montreal – Parc Dickie Moore

Text by Marie-Claude Allard, M.A.

Overview

In 2021, the City of Montreal launched a program to promote two complementary initiatives: green street drainage infrastructure and sponge parks. The team responsible for these initiatives, led by Marie Dugué, Section Head of Planning and Major Projects, Water Services, was tasked with providing tools, advice, and financial assistance to boroughs and central services regarding green infrastructure for street drainage and sponge parks. Although these two components were developed simultaneously, they have distinct characteristics in terms of their scale and functions.

Green infrastructure on streets includes, among other things, vegetated curb extensions located at a lower level than the roadway that capture and infiltrate runoff during light rainfall. The main purpose of such interventions is to reduce sewer overflows by managing small amounts of precipitation. This also promotes greening, reduces heat islands, and improves pedestrian safety.

For their part, sponge parks temporarily capture large volumes of water during heavy storms. Water from surrounding streets is directed at the surface toward a low-impact area (the park), held there, and then returned to the sewer once capacity becomes available again. The purpose of sponge parks is to reduce the frequency of flooding for the surrounding neighbourhoods.

Referring to the severe storms that hit Montreal in recent years, Dugué explains, “Every time it rains, water enters the street drains. Recently, we’ve had some very severe storms. We had two in 2024, we had others in 2023, and for several years now, we have been experiencing events that exceed all the statistics we usually have. And now, in the sewer system, the water can no longer get in because there is too much water falling on the street. That’s when we try to direct these rivers of water flowing along the streets toward these parks. We want to flood an area of lesser impact in order to protect or reduce the frequency of flooding in residential and commercial areas. So we often hold the water temporarily until the sewer has capacity again. Then, we return the water to the sewer system.”

Since 2022, the City of Montreal has implemented 23 sponge parks. Here is a list of the five largest sponge parks as of 2025, along with their retention capacity:

Pierre-Bédard Park / 5,735,000 liters
Pilon Park / 1,373,000 liters
Park at the intersection of Joseph and Dupuis streets (name to be determined) / 1,067,000 liters
Howard Park / 750,000 liters
Pierre-Dansereau Park / 627,000 liters

As for green infrastructure, since 2022 the City of Montreal has reached 2,500 “cells” (meaning individual units or functional modules that make up a stormwater management system), either built or under construction, for a total area equivalent to about 6 soccer fields, or roughly 45,000 m².

Related benefits

Although these two components bring greenery to the city and reduce heat islands, one aspect of this project that should not be overlooked is the effort and motivation of the teams. As part of a project that is now proving its worth, each team involved is proud to be part of such an initiative. As Dugué explains, “What also helps a lot is when you have good examples. Then things start to fall into place.”

During this period, Ms. Dugué’s team not only carried out pilot projects in urban areas, but also thought strategically about how to continue the actions thereafter.

Hugo Bourgoin, media relations officer with the City of Montreal’s Public Affairs and Protocol Department added, “What’s wonderful about sponge parks is that 99% of the time, they provide co-benefits. These spaces are used by citizens. Children can go play there, families can picnic in these parks, they use them. And the 1% of the time when rain is too intense and the sewer system can’t keep up, the park is partially flooded to accommodate that volume of water and relieve some of the pressure on the sewer system.”

A now quantifiable goal

In 2022, the city set a quantitative target: to build 8,500 m² of green infrastructure on streets between 2022 and 2025 and to provide 9,000 m³ of retention capacity in parks over the same period.

These projects would not have been possible without funding from the Ministry of the Environment. Through the green economy program, the city obtained $117 million for various elements, including $15.5 million dedicated to water services. This made it possible to assemble a team of experts to support the boroughs and central services carrying out the projects, producing tools, and conducting research.

As Dugué explains, these projects are cross-sectoral: “Of course, the project leaders are mostly in the boroughs; they are either in the boroughs or the central service, which is actually the Urban Planning and Mobility Department. The Parks and Sports Department also own these spaces and initiate the projects, commission consultants or design them internally, and supervise the work afterwards. My team is really there to support these teams in integrating water management. One of the interesting players is the Office of Ecological Transition and Resilience, which helps us find funding and increase various benefits.”

Finally, other sources of funding came from the Green Municipal Fund, the Flood Resilience and Adaptation Program (Programme de résilience et d’adaptation face aux inondations – PRAFI in French only), and the Sustainable Stormwater Management Program (Programme pour la gestion durable des eaux de pluie – PGDEP in French only), which are programs of the Ministry of Municipal Affairs, as well as the Disaster Mitigation and Adaptation Fund (DMAF), which is a federal program.

Implementation approach

To properly analyze the environment targeted by the project, the team used topographical data. This made it possible to assess street slopes, catchment areas draining towards a park, and vulnerable low-lying zones.

As Dugué explains, “It’s important to understand that we took a very opportunistic approach, which may be a little different from other municipalities. In other words, the City carries out a great deal of rehabilitation work to maintain its assets, including its sewer and water systems under the streets. So we are rebuilding the entire street with sewers and water mains, and we are also doing a lot of work to refurbish our parks. So whenever work was planned, we tried to integrate water management into it as well as we could.”

The goal is to better understand the basin areas in the city in order to identify the most vulnerable areas. Subsequently, the structures built in Montreal’s database are listed for asset management purposes.

Challenges and governance

The main challenge in this project is to train and coordinate a multitude of stakeholders across 19 boroughs. These stakeholders may include planners, landscape architects, engineers, planning and specification teams, contractors, maintenance workers, and external professionals. The team chosen must therefore consolidate and coordinate all of these stakeholders, which can be a challenge in itself.

Tools have been put in place to strengthen the capacities of those involved in this project. Approximately 200 training sessions have been provided citywide, as well as internal and external webinars on planning and design, developed by the Regional Council for the Environment (Conseil régional de l’environnement – in French only). In terms of published tools, catalogs, design and construction checklists, and videos documenting maintenance have been used to support those involved.

Outreach and external exchanges

The sponge parks project in Montreal attracts many visitors and encourages the sharing of experiences. In fact, many municipalities in Quebec, as well as countries such as South Korea and New Zealand, are interested in this project.

“We also participate in pan-Canadian working groups to share our experiences. We were recently invited to Singapore to present our projects. This has helped raise our profile,” explains Dugué.

The comments from Montreal citizens about sponge parks are generally very positive. There is increasing use of these spaces by the population. However, the current issue hanging over this project, an issue that could be described as a challenge, is its popularity.

“We are actually victims of our own success! The workload is increasing significantly,” says Dugué.

The success of sponge parks and green infrastructure on streets in the City of Montreal demonstrates an innovative approach that can inspire communities here and elsewhere. With this growing interest, it will be interesting to see where new collaborations will emerge to build a more sustainable urban future.

This project is carried out with funding from the Federation of Canadian Municipalities’ Green Municipal Fund
and the Government of Canada.