Canada Day storm: City of Ottawa says some areas received 167 mm of rain

The Ontario government says help for flood-stricken residents is coming, but there’s still no timeline for it. CTV’s Katelyn Wilson reports.

The Canada Day storm that flooded hundreds of basements and streets in Ottawa’s west end was a one in 200-year rainfall event, with some areas receiving more than 140 millimetres of rain, according to the City of Ottawa.

The clean-up continues after a series of thunderstorms hit Ottawa on July 1. The city has received 5,423 reports of basement flooding and collected more than 1,700 tonnes of storm waste since the storm. The city’s 3-1-1 line has received 5,423 service requests related to the flooding and extreme weather.

Environment Canada reported 118 millimetres of rain was recorded at the Ottawa Airport on July 1.

City council will receive an update on the city’s response to the Canada Day storm and flooding on Wednesday.

In a memo to council on Saturday, Infrastructure and Water Services general manager Tammy Rose said the city’s rain gauges show the rainfall totals varied across the city, from 15 mm at Trim Road in the east end to “as much as 167 mmm at the Britannia Station in the west end.”

“The highest rainfall amounts were concentrated in central and western Ottawa, including Britannia (167 mm), Colonnade (151 mm), Nepean (144 mm), Mooney’s Bay (117 mm), and St. Gabriel (114 mm), while many eastern and rural locations recorded substantially lower totals,” Rose said.

“This pattern demonstrates the highly localized nature of the storm, with some neighbourhoods receiving more than ten times the rainfall recorded at other locations within the city.”

According to the city, rainfall totals varied from 95 to 104 mm in Kanata, 104.4 mm at the Walter Baker Centre, 99 mm in Riverside South, 68 mm at Brewer Park, 61 mm at Lemieux Island, 48.4 in the Lees Avenue area and 15 mm to 19 mm in the east end.

Ottawa rainfall The City of Ottawa released a map showing rainfall totals from the July 1 storm. The totals vary from 15 mm at Trim Road to 144 mm in Nepean, 151 in the Colonnade neighbourhood and 167 mm in Britannia. (City of Ottawa memo)

Rose says a common storm in Ottawa between the spring and fall is often in the range of 5 to 15 mm of rainfall, with peak storm intensities of 5 to 15 mm per hour.

Rose notes Ottawa received a peak rainfall volume of 167 mm in five hours, with many areas experiencing a storm “close to or exceeding a 1 in 200-year event.”

By comparison, some areas of Ottawa received 107 mm of rain on Aug. 10, 2023 in five hours, which exceeded the 1 in 100-year event. A storm on Oct. 29, 2017 saw peak rainfall of 142 mm over 24 hours, which also exceeded the 1 in 100-year event, according to the memo.

Flooding in Ottawa Municipal garbage contractors remove garbage from homes that flooded during the storm on Canada Day, in the Qualicum – Graham Park neighbourhood of Ottawa, on Tuesday, July 7, 2026. THE CANADIAN PRESS/Justin Tang Flooding in Ottawa Belongings damaged after a storm on Canada Day flooded basements are seen on lawns to await disposal, in the Qualicum – Graham Park neighbourhood of Ottawa, on Tuesday, July 7, 2026. THE CANADIAN PRESS/Justin Tang Flooding in Ottawa Mike Dumond throws out material from his basement that was flooded in a significant storm on Canada Day, in the Qualicum – Graham Park neighbourhood of Ottawa, on Tuesday, July 7, 2026. THE CANADIAN PRESS/Justin Tang Flooding in Ottawa Municipal garbage contractors remove garbage from homes that flooded during the storm on Canada Day, in the Qualicum – Graham Park neighbourhood of Ottawa, on Tuesday, July 7, 2026. THE CANADIAN PRESS/Justin Tang Flooding in Ottawa Belongings damaged after a storm on Canada Day flooded basements, are seen on a lawn awaiting disposal, in the Qualicum – Graham Park neighbourhood of Ottawa, on Tuesday, July 7, 2026. THE CANADIAN PRESS/Justin Tang Your Morning Ottawa Update: Flooding clean up still underway Latest on Ottawa flooding cleanup efforts Crystal Beach Trash and construction materials outside homes in Crystal Beach. (Dylan Dyson/CTV News Ottawa) Crystal Beach Trash put outside of homes in Ottawa’s Crystal Beach neighbourhood after July 1 flooding on July 6, 2026. (Dylan Dyson/CTV News Ottawa) Garbage in Ottawa following flooding Garbage piled high outside the homes of residents affected by flooding in Ottawa. July 3, 2026. (Tyler Fleming/CTV News Ottawa) Theresa Kavanagh Ottawa councillor Theresa Kavanagh is among the residents affected by flooding. Her home’s basement filled with nearly a meter of sewage water. July 3, 2026. (Tyler Fleming/CTV News Ottawa) Flooded parking lot in Ottawa A flooded parking lot near a McEwen Avenue apartment building in Ottawa. July 2, 2026. (Courtesy: Becky Maracle) Flooded basement An Ottawa resident took this photo of the flooding in their basement on July 1, 2026. (Submitted) Garbage after flood Garbage is placed outside a home in Ottawa on Thursday, July 2, 2026, following a record-breaking rainstorm on July 1, leading to flooding across the city. (Tyler Fleming/CTV News Ottawa) Ottawa rain A car submerged in water outside a high-rise apartment building on McEwen Avenue in Ottawa. Ottawa received 118 mm of rain on Wednesday, causing flooding across the city. (Hydro Ottawa/X) Ottawa rain Ontario Provincial Police shared an image of flooding on Highway 417 at Holly Acres Road in Ottawa’s west end on Wednesday. Environment Canada says Ottawa received 110 mm of rain. (Michael Fathi/OPP) Canada Day Ottawa Heavy rain and severe storms caused flooding in parking lots and on streets across Ottawa on Canada Day. (Camille Wilson/CTV News Ottawa) Canada Day A car drives through a giant puddle at a gas station in Ottawa’s west end. Ottawa received more than 100 mm of rain on Canada Day, causing flooding on several roads across the city. (Camille Wilson/CTV News Ottawa) Canada Day rain A car with Canadian flags stops in flood water on Highway 417 in Ottawa’s west end on Wednesday. Ottawa received more than 100 mm of rain on Canada Day, causing flooding on several roads across the city. (Camille Wilson/CTV News Ottawa) Ottawa rain Ottawa received more than 100 mm of rain on Canada Day, causing flooding on several roads across the city. (Camille Wilson/CTV News Ottawa) Canada Day rain Ottawa received more than 100 mm of rain on Canada Day, causing flooding on several roads across the city. A tow truck operator works to help a driver submerged in Ottawa on Iris Street in Ottawa’s west end. (Camille Wilson/CTV News Ottawa) Canada Day ScreenA car is submerged in water on Highway 417 in Ottawa’s west end on Wednesday. Ottawa received more than 100 mm of rain on Canada Day, causing flooding on several roads across the city. (Camille Wilson/CTV News Ottawa)shot Highway 417 Flooding was reported in the eastbound lanes of Highway 417 at Pinecrest Wednesday evening as heavy rain hit Ottawa. (Ministry of Transportation/cameras) Ottawa infrastructure

The heavy rainfall on July 1 caused flooding on roads and in basements and sent millions of litres of untreated sewage flowing into the Ottawa River from the sewer system.

Rose says the city’s drinking water system, wastewater treatment plant, pump stations and emergency response systems “continued to function and provide core services,” but the “extraordinary volume and intensity of rainfall” exceeded capacity.

“The storm sewer systems across the city were operating over capacity, resulting in some stormwater travelling across the surface rather than through the pipe system,” Rose said.

“This led to significant surface ponding in low-lying areas and a significant number of basement flooding incidents and substantial combined sewer overflow.”

Rose says there are “several possible entry points for water to enter basements,” including stormwater backing up through storm service connections, groundwater penetrating foundations through cracks and joints and surface water entering through doors and window openings.

The City of Ottawa has launched a “comprehensive review of this extreme weather event,” to look at system performance and identify opportunities for improvement, according to Rose.

The memo says staff will undertake the following activities and studies:

Review previous flooding studies, historical flood records, and recommendations from past events. Document infrastructure and operational improvements that have been implemented and assess how they performed during this event. Prepare a summary report of flooding impacts across affected neighbourhoods, including an analysis of approximately 5,500 service requests. This will be supported by an engineering consultant, Rose said.3-1-1 requests

Residents of College Ward and Bay Ward filed the most requests to 3-1-1 about flooding following the storm.

The city received 5,423 calls for service following the July 1 storm.

The data shows there were 2,282 service requests from Ward 8 (College) and 1,512 service requests from residents in Ward 9. There were also 684 service requests from Knoxdale-Merivale and 427 requests from residents in Kanata North.

Storm cleanup

The city says 1,700 tonnes of storm waste has been delivered to the Trail Road Waste Facility since the storm on July 1.

A second round of storm-waste collection will begin on Monday in all impacted wards.

The three-item garbage limit has been lifted for residents living in the area.

Residents in Ottawa’s west end continued the cleanup on Saturday.

“It has been heartbreaking and a whirlwind and just trying to stay strong for my family,” Megan Fyfe told CTV News Ottawa’s Natalie van Rooy.

“I am just working day-to-day. I can’t even think beyond this afternoon.”

Fyfe said work was underway to pull out the drywall in her flooded home to begin the repairs.

Brent Gavin was dropping off items at an electronic waste location the city set up.

“I’m not going through any insurance claims or anything, it’s just not worth it,” Gavin said.

“I’ve done all the clean-up myself and I want that time and energy to be spent on those who need it a lot more than I do right now.”

Ottawa flooding Contractors carry furniture out of a home that was flooded during the heavy rain on Canada Day. (Natalie van Rooy/CTV News Ottawa) Information sessions on Sunday

The City of Ottawa is hosting a community information session at Ben Franklin Place on Sunday.

The city says residents impacted by the storm can drop by between 1 p.m. and 5 p.m. to speak with city staff, the Insurance Bureau of Canada and the Canadian Red Cross.

Information on the following topics will be available:

Waste disposalHealth and safety when cleaning flooded homesBuilding codes and permitsReporting basement flooding or damaged infrastructureSupport programsInsurance processing

The city will also be holding community information hubs on Sunday from 10 a.m. to 4 p.m. at the following locations:

Carleton Heights Community Centre – 1665 Apeldoorn AveNepean Sportsplex, Entrance 1 – 1701 Woodroffe AvenueMaki House – 19 Leeming DriveJohn G. Mlacak Centre – 2500 CampeauRon Kolbus Centre – 102 Greenview Avenue