After a reprieve from rain in the form of two sunny, warm days, water levels keep rising on the Ottawa River and its tributaries, raising concerns about worsening flooding in the days ahead.
On Saturday, April 18, 2026, an orange level flood watch was in effect for the lower Ottawa River.
According to the Ottawa River Regulation Planning Board, as of around 9 pm on Saturday, April 18, water levels and flows continued to rise at all locations along the main stem of the Ottawa River as significant runoff from rainfall and snowmelt. Reservoirs—the various lakes created by dams along the river and its tributaries, are retaining spring runoff to reduce flooding in the downstream river system. Minor flood levels have been exceeded in most flood prone areas.
Levels should continue increasing over the next few days in all locations and start stabilizing on Monday. On April 18, peak level estimates were generally above 2025 peak levels but below 2023 peak levels. Over the next two weeks, levels are expected to plateau or slowly decline depending on weather.
According to Board data from the Hydro-Québec water level monitoring station at Grenville, the water level of the Ottawa River was 42.2 metres/138.5 feet on Saturday, which was an increase from 41.94 metres/137.6 feet on Friday, April 17.
