Flood Warning - April 24, 2025

Flood Warning - Pembroke District
Ottawa River

Thursday, April 24, 2025, 4:00 pm - The Ministry of Natural Resources – Pembroke District is advising area residents that a Flood Warning is in effect for areas along the Ottawa River most noticeably from Pembroke to Britannia. until Friday, May 02, 2025 (if not updated/replaced).

Recent rainfall combined with warmer temperatures has melted most of the remaining snow locally. Remnants of the snowpack through the northern portion of the Ottawa river watershed are expected to continue to melt sustaining elevated levels and flows. This combined effect is causing the water levels and flows of the Ottawa River to rise. 

Residents along the main stem of the Ottawa River, for the area of Lac Coulonge (near Westmeath) and downstream to Arnprior should Consider the following:
Accounting for the combined effect of the rapid snowmelt and the forecasted rain event, it is anticipated that these areas will exceed the flooding threshold along the Ottawa River at Lake Coulonge, and areas downstream (Chats Lake, and Lake Deschenes), as early as Friday April 25, 2025.

However, the maximum levels to be reached this week will be well below the historical high of 2019.

Residents that have been affected by high water and flow conditions in the past should take necessary precautions to protect/secure any vulnerable property in proximity to rivers and lakes and closely monitor developing conditions and regularly check for updated messages. 

Residents and visitors should exercise caution while around waterbodies and maintain close supervision of children and pets. The ministry is closely monitoring the weather and developing watershed conditions. Further updates will be issued as appropriate.

Technical Information

Description of Weather System

A low-pressure system is forecast to move into the area Friday. Rainfall and warm temperatures, associated with Friday's system is forecast to bring 10 to 25 mm of rain across Southern Ontario. An additional 5 mm to 10 mm of rain may occur due to thunderstorms today, and again tomorrow, across southern Ontario south of Parry Sound, Algonquin Park, and Pembroke.

Description of Current Conditions
The MNR continues to closely monitor local lakes, rivers and weather conditions. 

Levels and flows are expected to increase due to forecasted precipitation events and spring runoff from the central and northern parts of the Ottawa River basin. Levels are expected to rise over the next few days in all locations.

Flooding in low-lying areas is expected, and those areas currently experiencing high water levels or flooding can expect these conditions to continue. A close watch of local weather forecasts, special weather statements, and warnings is recommended.

The watershed Condition Statement – Water Safety for the remainder of Renfrew County Will be extended until Friday May 2, 2025.

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