Heavy summer rainfall over the weekend has left parts of the Laurentians and Haute‑Mauricie coping with landslides, flooded roads and disrupted services. Local officials have declared a state of emergency in L'Ascension after a landslide damaged as many as 20 roads and reportedly cut power to the entire community.
What happened and where
Ample moisture streaming north from the United States collided with a stalled atmospheric boundary over Quebec, producing a concentrated band of very heavy rain between Sunday and Monday. The intense downpours produced localized "bullseyes" of precipitation that overwhelmed terrain and infrastructure in several places.
According to regional rainfall observations, the worst totals included 96 mm at Papineau‑Labelle, 82 mm in Cold Lake and 76 mm near Windigo River. Lower but still significant amounts were recorded in urban areas: Trois‑Rivières measured 43 mm and Montreal received 31 mm.
| Location | Reported rainfall (mm) |
|---|---|
| Papineau‑Labelle | 96 |
| Cold Lake | 82 |
| Windigo River | 76 |
| Trois‑Rivières | 43 |
| Montreal | 31 |
Damage and disruptions
Municipal authorities reported landslides that have undermined roadways and left some routes impassable. In L'Ascension officials say as many as 20 roads were damaged and the community experienced a power outage affecting the whole municipality. Around La Macaza, several roads were closed because of flooding. Additional landslides were reported along Route 25 in Haute‑Mauricie, the primary connection between La Tuque and Wemotaci.
No injuries have been reported so far, but local authorities and emergency-management teams have warned that the situation remains unstable in some places where the ground is saturated and further slides are possible.
Advice to residents and travellers
Municipal leaders and provincial officials urged people to avoid affected areas. The main public-safety recommendations include:
- Do not travel into zones where roads are closed or where emergency crews are working.
- Stay away from riverbanks, steep slopes and areas where earth movement has occurred.
- Monitor local municipal notices and provincial road-condition bulletins for reopening timelines.
Officials emphasised that even if a road surface appears intact, the underlying ground can be unstable after intense rainfall.
Response and what comes next
Emergency crews and municipal works departments are assessing damage to determine where repairs are most urgent and to map detours. A state of emergency allows L'Ascension to mobilize resources more quickly and request provincial assistance if needed.
At this stage, authorities have prioritised reopening critical links and restoring power. Longer‑term repair work will depend on further assessments of slope stability and the extent of undermining along affected roads.
Context and climate note
Such intense, localized rainfall events have become more frequent in recent years across southern Quebec, posing increasing challenges for road design and slope management. While this report does not attribute any single event to long‑term climate trends, the concentration of moisture and stationary weather boundaries can produce the type of heavy downpours that triggered this weekend's damage.
Residents in affected areas should continue to follow updates from their municipal governments and Quebec's provincial emergency and transport authorities. Travellers are advised to consult road‑condition services and avoid nonessential travel through the Laurentians and Haute‑Mauricie until crews declare routes safe.
Further local updates will follow as officials release repair timelines and additional assessments of infrastructure damage.
