Watershed Conditions Statement – Water Safety
With warm temperatures and rain in the forecast, Maitland Conservation is issuing a Watershed Conditions Statement – Water Safety for the Maitland and Nine Mile River watersheds.
Recent surveying indicates that the water content in the snow pack is averaging 80 mm across the watersheds. The highest level is in the Harriston area where there is approximately 100 mm of water content. The warm temperatures forecast for Sunday and Monday will melt most of the snow pack except in forested areas. The rapid snow melt means that a fast runoff and river response is expected.
The extent of flooding will depend on how much rain falls on Monday evening. Currently the forecast is for 10 to 15 mm of rain. If rainfall is less than 15 mm, watercourses are expected to be bankfull with flooding restricted to traditional flood prone areas. Municipal staff have been asked to monitor local problem areas and be prepared for the closures of low lying roads.
Rainfall exceeding 15 mm could lead to significant flooding. If the watersheds receive 25 mm of rain on Monday, municipal staff should expect flooding to be similar to that experienced in December 2008. Maitland Conservation staff are carefully monitoring the forecast and an update on watershed conditions will be provided if warranted.
People should stay away from rivers, ditches, and streams. The combination of slippery banks, broken or unstable ice and fast moving cold water will be dangerous. Any remaining ice cover on the river is not safe to be out on.
Flows are expected to remain high throughout next week. This message will remain in effect until 10:00 a.m. on Friday March 13, 2020.
Stephen Jackson, Flood and Erosion Safety Services Coordinator
Jayne Thompson, Communications and GIS-IT 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.