Forecast Schedule and Frequency:
Forecasts will resume for the spring freshet of 2024 or if unusually wet weather leads to increased flood risks.
During the spring freshet, forecasts are updated Monday to Friday (and weekends when conditions may change rapidly).
During the spring freshet period, you may click on any marker to see additional information for this location and to access a Graph View of the data. Graph View is also accessible by clicking on any location in the table below.
- Level forecasts correspond to predicted level at the end of the day (11:59pm) on the specified date.
- Discharge forecasts correspond to predicted average daily discharges for specified dates.
- Note that water levels are measured in metres above mean sea level.
- The water levels forecasts do not account for local variations due to wind and wave effects.
Please read the important warning at the bottom of the page.
To find out how the Ottawa River Regulating Committee communicates important hydrological information about the Ottawa River to responsible provincial authorities, please click here.
- These forecasts are prepared by the Ottawa River Regulating Committee to inform the collaborative management of principal reservoirs within the Ottawa River basin. These forecasts are used by provincial and federal government responsible authorities to assess flood risks. Only these authorities are responsible for disseminating forecasts to the public.
- These forecasts are based on the anticipated effect of reservoir regulation and on hydrological forecasting of natural inflows for a given weather forecast.
- Absolute accuracy of weather forecasts cannot be guaranteed. In addition, there are inherent uncertainties in the hydrologic models used to estimate inflows and the measurements of water levels and flows at various locations.
- The degree of uncertainty of these forecasts increases with the length of the forecasting horizon.
- Except in unusual circumstances, the table is updated in the afternoon and only on business days.
- The flow rates and actual levels can change rapidly without warning, particularly during the freshet period. We advise those using bodies of water to exercise caution and to always follow established safety guidelines when near water.
- Users of the flow data, water level data, and hydrological forecasts shown on this website must recognize that such information is considered preliminary data. Users must therefore accept that the information provided carries an unspecified level of uncertainty and are advised to be cautious if they intend to use the information for decision-making. Please see the Disclaimer for further details.
About this map
The coloured markers on this map depict conditions (level or flow) as a range of conditions categorized in three groups: for normal conditions, for above normal, for below normal. Click on any marker to see the most recent data from this location and what type of data is measured there. To view data related to the principal reservoirs in the basin, select ‘Reservoirs only’ in the upper right corner. Near real-time and historical data is available for additional locations by selecting ‘Graph View and Advanced Data’. Water levels at 24:00 means at midnight.
The data provided by this web service may not be reproduced or redistributed. Contact the Ottawa River Regulation Secretariat (see Contact us) for information on how to obtain historical data directly from the data owner.
Users of flow data and water level data shown on this website are cautioned to consider the unverified nature of the information before using it for decisions making. Please see the Disclaimer for further details.
The flow rate and actual levels can change rapidly without warning, particularly during the freshet period. We advise those using bodies of water to exercise caution and to follow safety rules at all times.
Understanding Range of Conditions:
The three ranges are based on percentiles, which are computed from the observations of the current day of the year over the last 30 years. The percentile (P) is the percent of all data that is lower than the actual value for the current day of the year.
: normal conditions, between P25% and P75%
: above normal conditions, P is equal or greater than P75%
: below normal conditions, P is lower than P25%