FLOOD WARNING Mattawa River subwatershed including the Town of Mattawa

FLOOD WATCHLake Nipissing shoreline areas in NBMCA watershed including parts of nearby creeks

(North Bay May 12, 2023). A FLOOD WARNING continues for the Mattawa River subwatershed including the Town of Mattawa, according to the North Bay-Mattawa Conservation Authority (NBMCA).

A FLOOD WATCH continues for the Lake Nipissing shoreline in the NBMCA watershed including areas in North Bay along Parks Creek from Marshall Avenue to the Lake; Chippewa Creek from Main St to the Lake; and La Vase River from Riverbend Rd to the Lake. Note that a Flood Watch has ended for other areas in the NBMCA watershed.

“The Ottawa River water level at Mattawa has decreased by around 92 cm since May 8, but water levels remain high. A Flood Warning is extended for the Mattawa River subwatershed including the Town of Mattawa,” said Angela Mills, NBMCA Flood Duty Officer. “The water level on the Ottawa River at Mattawa is expected to decrease further this week, based on information from the Ottawa River Regulation Planning Board.” Some low-lying areas in and around the Town of Mattawa may continue to be affected. Caution is urged, as the flows are still high on the Ottawa River. The Ottawa River water levels are managed by dams and reservoirs operated by provincial and federal governments. The Ottawa River Regulation Planning Board posts current data and forecasts on their website https://ottawariver.ca/

For comparison, when river-based flooding occurred at Mattawa in May 2019, the water level on the Ottawa River at Mattawa reached a maximum level that is about two metres higher than the present level. Flows from the Otto Holden dam in May 2019 at their maximum were around 80% greater than present.

“A Flood Watch continues for the Lake Nipissing shoreline area and the nearby parts of Parks Creek, Chippewa Creek, and La Vase River, as these areas are influenced by high lake levels,” said Chitra Gowda, NBMCA CAO. “The lake water level is not expected to increase; however strong winds and wave action are a concern while lake levels remain high,” she added. The water level on Lake Nipissing is regulated by dams operated by the federal government. Current water levels can be viewed by searching Station Name “Lake Nipissing” at https://wateroffice.ec.gc.ca/search/real_time_e.html

The Flood Watch for all other areas in the NBMCA watershed has ended.

Residents, especially those in low-lying areas, are encouraged to monitor the conditions as they develop, and prepare accordingly. Shorelines of creeks and rivers will be 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 shorelines. 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 – North Bay District.

As part of the NBMCA Flood Forecasting and Warning Program, staff will continue to monitor weather and watershed conditions and update this message based on the changing weather/streamflow conditions. Staff remain in contact with municipalities and other partners as required.

The general public is advised of these messages through the www.nbmca.ca website with the flood status icon and a link to information about current conditions. NBMCA also circulates these messages to local media and social media, posting on Twitter (@theNBMCA), Facebook (@theNBMCA) and Instagram (nbmcainfo).

This message will be in effect until (or updated before) Wednesday, May 17, 2023 at 4:00 pm.

-30-

CONTACT:

Angela Mills, Duty Officer, cell: 705-497-4668
Chitra Gowda, CAO, cell: 705-477-0372

Terminology: Notification Levels

Spring Freshet 2023 & Flood Bulletins