Flood Forecasting & Warning

SNC maintains a flood warning system in the watershed to provide the latest information to municipalities, media, emergency response services, and the Ministry of Natural Resources and Forestry.

Our flood warning system is two-fold:

1. To provide advance notice of flood conditions to member municipalities and the public, so that preparation measures can be taken to minimize the impact on people and property; and

2. To provide on-going updates of flood forecasts and watershed conditions during a flood event.

Ontario’s 36 Conservation Authorities are mandated to provide this flood forecasting and warning service. SNC, in partnership with the Ministry of Natural Resources and Forestry, maintains a network of stream gauges, rain gauges and snow course sites in the watershed. This data is used to quantify the components of the hydrologic cycle. Monitoring can also include visual inspections of watercourses.

Click here to explore the Ministry of Natural Resources and Forestry Ontario Flood Map

Learn more about current water levels and flows in the watershed here.

We perform a daily planning cycle to ensure that the flood potential can be identified in a timely manner. This includes an analysis of the following parameters:

  • Daily calculation of the 7:00 a.m. flows;
  • Daily check of forecasts for weather conditions, precipitation and temperatures; and
  • Snow and ice survey data.

We use this analysis to predict the flood potential and issue the appropriate message.

Learn more about how to be prepared; before and after a flood here.

What do flood messages mean?

Normal: No flood conditions exist.


Watershed Conditions Statement—Water Safety: High flows, unsafe banks, melting ice or other factors that could be dangerous for recreational users such as anglers, canoeists, hikers, children, pets, etc. are present. Flooding is not expected.


Watershed Conditions Statement—Flood Outlook: Early notice of the potential for flooding based on weather forecasts calling for heavy rain, snow melt, high wind or other conditions that could lead to high runoff, cause ice jams, lakeshore flooding or erosion.

Flood Watch: Flooding is possible in specific watercourses or municipalities. Municipalities, emergency services and individual landowners in flood-prone areas should prepare.


Flood Warning: Flooding is imminent or already occurring in specific watercourses or municipalities