By 2050 there will be an increased likelihood of extreme weather events such as flooding, heat waves, ice storms and severe winds.

Ottawa’s weather is becoming more variable and unpredictable. In recent years we have experienced more extreme heat, wind, rain and winter storms. Some examples of extreme weather events in Ottawa include:

• Five successive ice storms in January 1998, which caused massive damage to trees and electrical infrastructure causing widespread power outages and a shutdown of activities across Ottawa and the region for several weeks. The storm is the second most expensive natural disaster in Canadian history with $2.3 billion in insurance payouts.
• Over 50 cm of snow in February 2016, which caused closures throughout the city and set a new record for the biggest snowfall in a single day
• Significant flooding along the Ottawa River in the spring of 2017 and 2019 resulted in extensive property damage and health concerns
• Tornadoes in 2018 and 2019 caused extensive damage to property and prolonged power outages.
• A prolonged extreme heat event that lasted six days in July 2018. On Canada Day, at the hottest time of the day, humidex levels made it feel like 47 degrees Celsius.
• The Ontario-Quebec derecho in May 2022 that killed 10 people, caused widespread property damage and left hundreds of thousands of people in Ottawa without power for several days. The storm is the sixth most expensive natural disaster in Canadian history.

What we are expecting

By the 2050s, under a high-emission scenario, we can expect:

• Favourable conditions for ice storms or severe snow storms, tornadoes and high wind gusts, droughts and wildfires
• Increase in freezing rain and ice storms – the colder months will likely see more freezing rain due to the increase of days around zero degrees Celsius.

You can find out more details of what to expect in the 2030s and 2080s in the Summary of the Future Climate in Canada’s Capital Region.

What are the top risks from an increase in extreme events?

• Increased winter maintenance of roads, sidewalks and pathways due to freeze-thaw cycles and freezing rain
• Increased risk of slips and falls and isolation due to icy sidewalks
• Reduced ability of City and community services to effectively respond to simultaneous or repeated extreme events
• Extended power outages when electrical infrastructure is damaged
• Reduced access to essential services such as healthcare, education, food banks and transit during extreme weather impacting residents

More information about the climate impacts facing Ottawa is available in the Climate Vulnerability and Risk Assessment.

Who is most vulnerable?

Extreme events put everyone at risk, but they disproportionally impact populations such as Indigenous Peoples, older adults, low income, homeless and racialized people. More remote rural populations may have reduced access to roads and utilities. Persons with disabilities or mobility issues may be homebound as they wait for snow and ice to be cleared. Those living in communities that have experienced past emergencies may also experience increased anxiety.

How can you prepare?

We all have a role to play in preparing for the impacts of changing weather patterns and extreme events. Find out what you can do, what the City is doing and visit the Resource Hub (coming soon) where we have additional resources that can help communities prepare for climate change.

Thank you to everyone who has provided input into the Climate Resiliency Strategy. We received over 500 responses to the surveys. A summary of responses can be found in the What We Heard Report. The key findings are summarized below. This is an updated version of the Interim What we Heard Report that was released in June, 2021.

Key findings from Ottawa residents, businesses, institutions and organizations:

• 92% of respondents are very concerned or concerned about climate change
• The top three concerns about climate change are:
  • The increase in the number of heatwaves and the number of hot days above 30 degrees Celsius (78%)
  • Changes in the natural environment (71%)
  • Increased risk of flooding (70%)
• The most common impacts experienced by respondents are heatwaves (77%), changes in the natural environment (50%) and high winds/tornadoes (49%)
• When asked to describe how they’ve been affected respondents told stories of their property, health, operations or lifestyles being impacted by extreme weather events (heatwaves, drought, flooding, tornadoes, ice storms), Lyme disease and increased winter temperatures
• Just over half (50%) say they are very prepared or somewhat prepared for the impacts of climate change. 31% say they are not prepared
• Taking steps to keep safe in the sun and keep homes cool were the most common actions that respondents are already taking followed by protecting against ticks and mosquitoes. Developing an emergency preparedness plan, checking in on neighbours during extreme heat events and protecting against ticks and mosquitoes were the most common actions that respondents are planning to do.

Input from the surveys was considered during the Climate Vulnerability and Risk Assessment and will be used to help inform the Climate Resiliency Strategy.

We look forward to hearing more from residents and stakeholders as we develop the Climate Resiliency Strategy. We encourage you to stay engaged and informed by:

• Signing up to the climate change e-newsletter
• Regularly checking this page for updates

The Climate Resiliency Strategy will review the impacts of climate change, assess where the City is vulnerable and prioritize solutions. The City has been addressing climate change risks for many years, including the following initiatives:

• An Emergency Management Plan to prepare and respond to the needs of the community during a major emergency such as flooding, while still ensuring continuation of essential services
• Environmental health education, awareness and response plans to reduce climate related illnesses and deaths associated with ultra violet radiation, extreme heat and humidity, cold weather, poor air quality (including wildfire smoke), flooding, Lyme disease and West Nile virus.
• Applying a climate and health lens to the new Official Plan (policies that guide the building of the city) and its supporting documents to build energy and climate resiliency into future growth and development. The new Official Plan integrates climate change mitigation and adaption policies throughout. For example, it includes revised policies to reduce the impacts of the urban heat island effect, reduce risks in areas vulnerable to flooding and protect our natural and agricultural areas.
• Raising awareness of the link between health and the built environment and highlighting how residents can get involved to make changes in their communities to become more resilient to climate change.
• Using urban heat island maps to better understand what areas are impacted by hot weather, and to inform policies that will reduce the urban heat island effects to better protect public health.
• Supporting community gardens to encourage local production of food
• Building our infrastructure to be resilient in future climate conditions such as extreme weather, greater rainfall and higher temperatures. For example:
  1. new City sewers are designed to handle larger rainfall events to reduce the risks of flooding.
  2. the City’s wastewater treatment plant is being upgraded to permit the plant to operate independent of the utility grid, using power produced on site to so it can remain operational in the event of a sustained power failure.
  3. using asphalt that is more resistant to temperature fluctuations for roads, pavement and parking lots
  4. the new Combined Sewage Storage Tunnel will greatly reduce the frequency of sewage overflows during storms from entering the Ottawa River and reduce the risk of basement flooding in downtown neighbourhoods.
  5. flood response plans are in place at the City’s two water purification plants to protect this critical infrastructure during a flooding event along the Ottawa River, in order to ensure continued drinking water supply
• Growing Ottawa’s urban forest and making it healthier, more diverse and resilient through the Urban Forest Management Plan.
• Supporting homeowners with grants for backwater valves through the Residential Protective Plumbing Program
• Supporting farmers to adopt new technologies that protect soils and enable them to manage variable rainfall events through the Rural Clean Water Program
• Promoting sustainability and building resiliency in the agriculture and agri-food industry through innovation and knowledge transfer at the Ottawa Smart Farm, which focuses on leveraging technology to help producers optimize their efforts and overcome challenges such as changes in growing seasons and extreme weather events.