The Oldman River is running faster on Canada Day 2026 than it did at the height of June's flooding events, and the City of Lethbridge is asking residents to stay away from its banks.
The City issued an update at 9:45 a.m. July 1 reporting the Oldman River is flowing at 900 cubic metres per second. That is above the flow rates seen in early June, when the city's previous high reached 746 m³/s before dropping back. Normal flow for the Oldman at this time of year runs between 200 and 250 cubic metres per second. Today's reading is roughly four times that.
The city was direct: "The river is extremely fast and dangerous and the banks are unstable. Do not go near the river's edge."
What is closed right now
Four parks have been closed until further notice due to the safety risk: Pavan Park, Popson Park, Alexander Wilderness Park, and Cottonwood Park.
All four sit in the river valley where fast-moving water, unstable banks, and debris make conditions dangerous. Check the City of Lethbridge website before heading to any river valley parks today.
No flood risk to homes but conditions are still serious
The City confirmed water and wastewater treatment plant operations remain stable. At 900 m³/s, the river is well below the threshold at which overland flooding begins threatening homes and infrastructure in Lethbridge. Alberta's flood hazard study for the Oldman River sets the design discharge for a major flood event at 3,320 m³/s above the St. Mary River confluence. The city is nowhere near that threshold.
What 900 m³/s does mean is that the river is moving fast enough to be immediately lethal for anyone who enters it. The banks are softened by weeks of above-normal rainfall and can give way without warning. Debris including trees and branches swept downstream reduces visibility and creates entrapment hazards. Water temperature remains cold.
Charles Schoening, Water Rescue Team Lead with Lethbridge Fire and Emergency Services, warned consistently through the June flooding that it is the banks that kill people, not just the water itself. "Riverbanks may be unstable; trails and access points may be slippery and debris in the water can create serious hazards," he said during those events. Those conditions are back today in a more serious form.
Why the Oldman River moves so fast so quickly
The Oldman River drains a massive watershed covering much of southwestern Alberta, including the Rockies and the foothills south and west of Lethbridge. When significant rainfall hits that catchment area — as it has repeatedly this summer — water from hundreds of square kilometres funnels into the river system within hours. The Oldman does not need it to be raining in Lethbridge itself for the river to spike. Rain falling in the Crowsnest Pass, the Porcupine Hills, or the Castle River watershed all drains toward Lethbridge eventually.
That is why the jump from normal to dangerous can happen fast and why the city's warning today specifically says conditions have risen quickly. The 160 mm that fell across the Lethbridge area between May 28 and June 2 saturated the ground. Every rainfall event since then runs off faster than it would into dry soil, adding volume to the river with less absorption along the way.
How this fits into Lethbridge's wet summer
This is not an isolated event. Lethbridge and southern Alberta have been dealing with above-normal precipitation since late May. The Oldman River peaked at 746 m³/s in early June during that event, prompting a boating advisory, park closures, and voluntary water conservation measures. The river dropped back and parks began reopening before today's new rainfall pushed it above that previous peak.
The pattern mirrors what has happened across central and southern Alberta this summer. Edmonton broke a 112-year June rainfall record. Calgary issued a River Safety Advisory covering the Bow and Elbow Rivers ahead of Stampede. Canmore and Kananaskis both declared states of local emergency in late June as precipitation continued to push rivers well above seasonal norms.
What to do if you are in Lethbridge today
Stay away from the Oldman River and St. Mary River. Keep children and pets away from the river's edge. Avoid river valley parks, including the four now officially closed. Obey all posted signs and barricades.
If someone falls into the river or you witness an emergency, call 911 immediately. Do not attempt a water rescue yourself.
For current conditions and park closure updates visit lethbridge.ca. For provincial flood information and river level data visit floods.alberta.ca.
Sources:
City of Lethbridge, July 1 Oldman River update, 9:45 a.m. July 1, 2026 (lethbridge.ca/news/posts/july-1-oldman-river-update)
City of Lethbridge, Higher streamflow but low risk update, June 2, 2026 (lethbridge.ca/news/posts/higher-streamflow-but-low-risk)
City of Lethbridge, June 3 Oldman River update (lethbridge.ca/news/posts/june-3-oldman-river-update)
Charles Schoening, Water Rescue Team Lead, Lethbridge Fire and Emergency Services, June 2026 statements
Government of Alberta, Lethbridge Oldman River Flood Hazard Study (open.alberta.ca)
