Lake Simcoe Shoreline
Water Levels and Shoreline Flooding
The Lake Simcoe Shoreline Hazard Watch and Warning messages are issued when there is a potential for high water levels and waves along the Lake Simcoe Shoreline that could lead to flooding and erosion. The shoreline hazard warning can be issued with, or independent of, the riverine flood messages.
Lake Simcoe Shoreline Hazards - Definitions

Normal Conditions
No flood conditions exist.
Low Risk:
- potential for minor localized shoreline flooding due to high lake levels with minimal impact or disruption
- minor local drainage issues

Shoreline Hazard Watch - Moderate Risk
- broader shoreline flooding due to high lake levels
- impacts to local drainage in low lying areas due to high lake levels and inability for effective drainage
- localized minor storm surge / seiche and wave damage may occur
- moderate risk to dike failures in the Keswick, Kolbar and Bradford polders impacting agricultural lands
Shoreline Hazard Warning - High Risk
- significant shoreline flooding due to extreme lake levels
- significant storm surge/seiche causing flooding in low lying shoreline areas exposed to prevailing winds
- high risk for dock, boathouse and shoreline damage for areas exposed to prevailing winds
- high risk to dike failures in the Keswick, Kolbar and Bradford polders impacting agricultural lands
Riverine Flooding
Lake Simcoe Conservation Authority also issues riverine messages to advise municipalities and watershed residents of the potential threat to public safety or property damage.
Learn more about our Riverine (rivers and streams) flood forecasting.