Watershed Conditions Statement – Flood Outlook
A Watershed Conditions Statement – Water Safety is in place for the North Bay-Mattawa Conservation Authority watershed.
Watershed Conditions Statement – Water Safety indicates that high flows, unsafe banks, melting ice or other factors could be dangerous for users such as anglers, boaters, swimmers, children or pets. Flooding is not expected.
If you have a flood emergency, please contact your municipality. If you live in an unincorporated township, please contact the Ministry of Natural Resources and Forestry (MNRF) – North Bay District.
Current Conditions:
In response to this week’s rain and melt event, water levels on many area lakes and rivers are normal for this time of year. The water level and flow on the La Vase River are above normal for this time of year. Moisture content in the snowpack is 61 mm (as of Mar 1), which is below normal for this time of year.
Current water levels can be viewed by searching Station Names “Ottawa River”, “Mattawa River”, “Chippewa Creek”, “La Vase River”, “Wasi River”, and “Lake Nipissing” at https://wateroffice.ec.gc.ca/search/real_time_e.html
Water levels on the Ottawa River are managed by upstream dams and reservoirs operated by provincial and federal governments. Forecasts are available at https://ottawariver.ca/
The water level on Lake Nipissing is regulated by dams operated by the federal government. Forecasts are available at https://www.tpsgc-pwgsc.gc.ca/ontario/eaux-water/renseignement-information-eng.html
Forecasted Conditions:
Weather forecasts indicate temperatures are rising again and are expected to remain above freezing from Saturday (Mar 2) until Tuesday night with temperatures ranging between 3 and 14 ºC. Forecasts indicate 10 to 25 mm of rain are possible Monday (Mar 4) into Tuesday. Daytime highs are forecast to remain above freezing for the remainder of the week with overnight lows returning to below 0 ºC late Tuesday.
The water level of the Ottawa River at Mattawa is expected to remain in the normal range, per the Ottawa River Regulating Committee.
Historic Flood Conditions:
For comparison, when flooding occurred in the watershed around April 18, 2019, the snowpack water content was 123 mm (measured April 15, 2019). Daytime temperatures were between 3 and 12 °C, with overnight temperatures above freezing. Actual precipitation measured on April 18, 2019 was 31.8 mm. When combined with snowmelt, the daily average water level on Chippewa Creek, in North Bay, increased by 57.6 cm in that one day.
Risk:
Forecasted warm temperatures and rain will trigger snow melt and increase hazardous conditions around lakes, rivers, and streams. Rain on frozen conditions may result in rapid changes in water levels on urban creeks in the City of North Bay, especially during and after periods of intense precipitation. Higher flows can break up the ice on streams and rivers. Water levels in the watershed will increase; however, widespread flooding is not expected at this time.
All residents, especially those in low lying areas, are encouraged to monitor the conditions that are developing. Banks adjacent to rivers and creeks are very slippery at this time and when combined with cold open water, pose a serious hazard. The public is encouraged to keep children and pets away from watercourses and off waterbodies.
Municipalities are encouraged to monitor water crossings for debris that may affect the movement of water through culverts and bridges. A close watch on local conditions and updated forecasts and warnings from Environment Canada is also recommended.
Staff at the North Bay-Mattawa Conservation Authority will continue to monitor weather and watershed conditions and update this message based on the changing weather and streamflow conditions.
This message will be in effect until (or updated before) Wednesday, March 6, 2024 at 4:00 PM EST.
