July 2026 Flooding Response and Recovery

The City of St. Catharines recognizes the significant impact this week’s extreme rainfall event has had on residents, families and businesses across our community. We know many are now dealing with flooded basements, damaged belongings and the stress and disruption that comes with recovery. The City continues to work through its recovery and response alongside its partners, and this page will be updated as new information and supports become available.

What happened?

Overnight July 27-28, 2026, St. Catharines experienced an extraordinary rainfall event that resulted in widespread flooding across the City, with a concentration in the north end. The storm system stalled over the north end of the City, resulting in heavy rainfall in the area. Rainfall totals reached approximately 138 mm in Port Dalhousie and 126 mm in Port Weller, with the heaviest rainfall occurring within only a few hours. That volume of precipitation over just a short period was significantly higher than the average rainfall for our community for the entire month of July, causing overland flooding.

The City declared a Significant Weather Event on July 28 and partially activated its Emergency Operations Centre to coordinate the response. Since the event began, City crews from across the organization have been working around the clock to respond to flooding impacts, assess municipal infrastructure, address priority health and safety concerns and support residents through the recovery process.

No indication of infrastructure failure

We understand residents have questions about what caused the widespread flooding, including concerns related to infrastructure, blockages, construction and growth.

Based on inspections completed to date, flooding was predominantly the result of the extraordinary volume and intensity of rainfall.

Municipal crews have inspected affected areas and, while localized concerns continue to be investigated, there has been no indication that a single blockage or isolated infrastructure issue was responsible for the widespread flooding. The Region of Niagara has indicated the same for their infrastructure, and says their water and wastewater infrastructure is operating normally. Reports of flooding have been received from neighbourhoods across much of the city, reflecting the widespread nature of this weather event.

The City's stormwater system is designed, maintained and operated to established engineering standards. However, no drainage system can be designed to eliminate flood risk under all conditions. The volume and intensity of rainfall experienced during this event placed significant stress on drainage systems across the city and contributed to widespread overland flooding impacts.

The causes of basement flooding can differ significantly from one property to another and may include surface water intrusion, elevated groundwater levels, sewer system surcharging, or a combination of factors. The City continues to investigate reported incidents; however, the geographic extent of impacts reported across the community suggests that multiple flooding mechanisms were likely contributors to this event.

The state of City infrastructure

Much of the infrastructure in our communities was designed based on historical weather patterns and standards that did not anticipate the frequency and severity of some of the extreme weather events we are experienced this week.

Stormwater systems are designed using a combination of underground sewer infrastructure and surface drainage routes. During exceptionally intense rainfall events, these systems can become overwhelmed, resulting in surface ponding, roadway flooding and water accumulating in low-lying areas.

The City continues to take a proactive, long-term approach to managing, renewing and improving infrastructure. Through the City’s Asset Management Plan, staff maintain a roadmap that guides infrastructure replacement, rehabilitation and investment decisions. These investments are made annually and prioritized based on asset condition, risk, community needs and available resources to ensure infrastructure continues to serve residents today and into the future.

Infrastructure capacity is also a key consideration as the community grows. New development and redevelopment projects are required to meet current stormwater management standards and demonstrate how water and will be managed to minimize impacts on surrounding properties and existing infrastructure.

What’s happening now?

The City recognizes that many residents are looking for answers as they continue the recovery process. As this continues, staff remain focused on supporting residents, responding to service requests and working with Niagara Region and provincial partners to identify available supports. The City has also been reviewing opportunities for additional assistance, including waste collection support for flood-damaged materials and other recovery resources that may become available.

Residents who experienced basement flooding are encouraged to:

• Contact their insurance provider as soon as possible to begin the claims process.
• Document any damage to their property.
• Remove standing water safely where possible.
• Visit the City’s basement flooding webpage for cleanup guidance, available resources and information about the Flood Alleviation Program (FLAP), which helps eligible homeowners install a sewer backup protection valve on their sanitary lateral.
• Report the incident to Citizens First if you haven’t already by calling 905.688.5600 or citizensfirst@stcatharines.ca

We will continue to update this page and our social media with other supports as they become available.

Additional Resources

The following additional links and resources are available to assist impacted residents and businesses:

·    211 Niagara

·   Red Cross Niagara Region Branch Emergency and Disaster Services

·   Province of Ontario flooding information and resources

·    Health Canada Flood cleanup safety information

·    Insurance Bureau of Canada Water Damage and Flood Protection

·    City of St. Catharines Flood Alleviation Program (FLAP)

·    Basement Flooding Prevention Guide (provides vital information on the sewer system, flood prevention, and more)

·    Niagara Region Emergency Management

·    Niagara Region Public Health

Niagara Region Waste Management