April 17, 2023 — This FLOOD WARNING statement is an update to the Flood Watch issued for areas along the Lower Ottawa River (Arnprior to Hawkesbury) on April 14th, 2023.      

      
Water levels are expected to continue rising within the Ottawa River Basin due to increased snowmelt associated with above normal snowpack and high temperatures over the weekend. 
 
Most of the water currently entering the Ottawa River is originating in areas where there are no reservoirs or retention capacity. The Ottawa River Regulating Committee is managing principal reservoirs to reduce river flows to downstream areas.  
 
The Ottawa River Regulating Committee anticipates that water levels along the main stem  
of the Ottawa River are expected to exceed major flood levels, impacting several streets, lawns and houses in low-lying areas. Flood levels are expected to remain well below historic high flood levels.  
 
Impacted locations include flood-prone areas at Chats Lake, Constance Bay area, Britannia /  
Lac Deschênes, Cumberland, City of Clarence-Rockland, Township of Alfred Plantagenet and 
other vulnerable areas down to Montreal. 
 
MVCA - Areas of Concern: 
•    Water levels in the Constance Bay area are expected to rise by about 0.70 m above the current elevation* over the next 2-3 days. 


RVCA - Areas of Concern: 
•    Water levels in the Britannia area (Grandview Road and the Belltown Community) 
are expected to rise by about 0.65 m above the current elevation* over the next 2-3 days. 
•    Water levels east of Cumberland Village (Boise Village, Morin Road, Leo Lane) 
are expected to rise by about 1.0 m above the current elevation* over the next 2-3 days. 

SNC - Areas of Concern: 
•    Water levels in the Rockland area are expected to rise by about 1.0 m above the current elevation* over the next 2-3 days. 

MNRF - Areas of Concern: 
•    Water levels in the Hawkesbury area are expected to rise by about 0.50 m above the current elevation* over the next 2-3 days. 
* Current elevation as of 9 a.m., Monday, April 17, 2023. 
 
Peak river conditions remain dependent on snowmelt and rainfall amounts. A rainfall event is forecasted next weekend that will add water to the river at a time when flows are near flood thresholds. There is uncertainty on the rainfall amounts and the areas that could be affected. 
 
Residents in flood-prone areas are encouraged to closely follow changing conditions and to take necessary measures. 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 and provide appropriate supervision around all waterbodies.  
 
The Mississippi Valley (MVCA), Rideau Valley (RVCA), and South Nation (SNC) Conservation Authorities monitor water levels and weather forecasts with the Ministry of Natural Resources and Forestry (MNRF) as part of the Flood Forecasting and Warning Program. Updates are provided as conditions change. 
 
The Ottawa River Regulating Committee will be reassessing forecast conditions and  
providing hydrological condition updates on its website daily at www.ottawariver.ca/forecasts
To view current flood warnings across Ontario, visit: www.ontario.ca/law-and-safety/flood-forecasting-and-warning-program.      
 
This FLOOD WARNING STATEMENT is in effect until April 28, 2023 at 5:00 PM.  
      
Mississippi Valley Conservation Authority

Contact: Jennifer North
Water Resources Technologist
613-253-0006 ext. 243
jnorth@mvc.on.ca   www.mvc.on.ca

 
Definitions: 
•    Water Conditions Statement: Water Safety: indicates that high flows, melting ice or other factors could be dangerous for such users as boaters, anglers, and swimmers but flooding is not expected. 
•    Water Conditions Statement: Flood Outlook: gives early notice of the potential for flooding based on weather forecasts calling for heavy rain, snow melt, high winds, or other conditions. 
•    Flood Watch: potential for flooding exists within specific watercourses and municipalities. Municipalities, emergency services and individual landowners in flood-prone areas 
should prepare. 
•    Flood Warning: flooding is imminent or occurring within specific watercourses 
and municipalities.