FLOOD WARNING: Ottawa River – Arnprior to Hawkesbury – Update #10

10-May-2019 10-May-2019

Weather Forecast:

Rainfall amounts of 10 to 15 mm is forecasted today, May 10.

Environmental Conditions:
Water levels along the Ottawa River from Mattawa to Montreal are increasing due to recent precipitation and spring runoff upstream in the Ottawa River basin.

Locations from Point Gatineau down to the Grenville/Hawkesbury area could see water levels rise, without exceeding the initial peak observed last week, depending on the amount of precipitation received.

All flood-prone areas along the Ottawa River from Lac Coulonge down to the Montreal Archipelago are at risk as snowmelt continues along the upper
Ottawa River.

Levels are expected to remain high for the next two to three weeks.

Risk is highly dependent on the amount of precipitation that is received.

Updates to all projections will be provided as they become available.

MVCA areas of concern: 

Water levels in the Constance Bay area are expected to increase over the next 24 to 48 hours but are expected to be 5 to 10 cm lower than last week’s peak elevations

RVCA areas of concern:
Water levels in the Britannia area (Grandview Road, Britannia Village, and the Belltown Community) are expected to increase over the next 24 to 48 hours but are expected to be 5 to 10 cm lower than last week’s peak elevations.

Water levels east of Cumberland Village (Boise Village, Morin Road, Leo Lane) are expected to increase over the next 24 to 48 hours but are not expected to exceed the peak levels observed last week.

SNC areas of concern:
Water level in Clarence-Rockland and Alfred-Plantagenet have risen 0.04m in the last 48 hours. Levels are expected to continue to rise over the next 24 to 48 hours without exceeding initial peaks observed last week.

Due to the forecast uncertainty it is difficult to accurately predict how quickly water levels will rise and when river conditions may peak.

Residents in flood-prone areas are encouraged to closely monitor conditions and take necessary actions. Sandbags are available to residents in flood prone areas. 

Residents are strongly urged to keep sandbags in place for at least the next
two weeks.

Residents are advised to stay away from watercourses where flows are high and where banks might be unstable. Parents are encouraged to explain dangers to children.


This Flood Warning is in effect until Tuesday, May 14, 2019 at 5:00 PM.

South Nation Conservation (SNC) and its Ottawa partners, the Rideau Valley and Mississippi Valley Conservation Authorities, monitor the water levels and weather forecasts with the Ministry of Natural Resources and Forestry as part of the Flood Forecasting and Warning Program. Updates are provided as conditions change.

The Ottawa River Regulation Planning Board will be reassessing forecast conditions and providing hydrological condition updates on its website daily at

Please visit for more information. To provide feedback with respect to changes in water related conditions please email, post on our Facebook (/SouthNationConservation) or Twitter (@SouthNationCA).

For more information regarding the Ottawa River, visit

FOR MORE INFORMATION: Omar Kana’n, SNC Water Resources Analyst,

FOR MEDIA INQUIRIES: John Mesman, SNC Team Lead of Communications,

FORWARDED TO: All Flood Forecasting and Warning Directory