Watershed Conditions Statement – Water Safety
Significant rainfall is expected over the next 48 hours. An approaching system will bring with it unseasonably warm temperatures, and significant moisture into Southern Ontario from the Gulf of Mexico.
Light showers are expected throughout today, followed by steady to heavy rain overnight and through Saturday. The current forecasted rainfall total across the Maitland and Nine Mile River watersheds is estimated at 50 mm through Saturday. An additional 25 mm of precipitation in the form of freezing rain is also expected on Saturday.
Current warm temperatures combined with rain will melt the snowpack adding an additional snow water equivalent of 10 mm of runoff to the rainfall totals. Based on current weather and streamflow forecasts, levels in watercourses will exceed bank-full conditions, resulting in minor flooding of traditional low-lying floodplain areas.
It is important to note that there remains some variability in the current forecast regarding the amount of precipitation that our watersheds will receive. At the moment the temperature is expected to drop below freezing by early Saturday afternoon. This will cause the rain to change to freezing rain, reducing the threat of flooding. If the temperature does not drop, and rainfall exceeds 75 mm, flood levels will be more significant and could be similar to those experienced in late Dec. 2008. Maitland Conservation will be monitoring conditions very closely over the next 48 hours and will provided an update if required.
Residents are reminded to use caution near all watercourses. Slippery and unstable streambanks, and extremely cold and fast-flowing water will combine to create hazardous conditions.
Jeff Winzenried, Water Resources Technician
Jayne Thompson, Communications Coordinator
519-335-3557 ext. 226 Cell: 519-357-6670
Types of Flood Messages:
Watershed Conditions Statement – Water Safety – General watershed conditions are being assessed for high runoff potential that could lead to flooding, and to remind the public of general river safety issues.
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. Municipalities and individuals should take action to deal with flood conditions. This may include road closures and evacuations.