Mattawa residents are bracing for significantly higher flood levels tomorrow.
"Water levels along the Ottawa River Watershed below Otto Holden Dam are seeing an increased rate of flow well above normal conditions," says the MNRF. "These higher than normal water levels will continue to increase from the current level of 155.28 m and forecasted to increase significantly to a peak that could exceed 155.70 m on Friday at the Town of Mattawa."
"The forecast from the Ottawa River Regulating Committee is that the water level for the Ottawa River at the Town of Mattawa is expected to increase 53cm (21") to 155.7m above sea level by Friday," says the North Bay Mattawa Conservation Authority. "It is anticipated that upstream water will be released from the Otto Holden dam sometime today. Levels could potentially reach historical levels. In July 1957, Hurricane Audrey struck and the Mattawa River reached a recorded high level of 155.7m."
Flooding in the low-lying areas in the Town of Mattawa and along the lower Mattawa River is a result of backwater from the Ottawa River. Substantial flow is being passed downstream from Temiskaming, due to the melting of unusually high snow depth to the north.
The Otto Holden dam is passing through the flow it receives from Temiskaming, which has a strong effect on the Ottawa River downstream and thus the backflow into the Mattawa River up to the Holdman Dam which can affect properties in Mattawa, Papineau-Cameron Twp and Mattawan Twp along the Mattawa River.
Lake Temiskaming water levels are currently sitting at 179.70 m and are forecast to rise another 0.5 m reaching 180.20 m over the next five days.
