Forecast for 2026-05-06

River conditions forecasts posted on 2026-05-06 by Ottawa River Regulating Committee

Spring runoff continues to decrease in the northern part of the basin with the melting of the last patches of snow. Water levels and flows on the Ottawa River from Mattawa to the Montreal Region continue to decline. Over the coming week, since no major rainfall is forecast on the northern part of the basin, water levels and flows are expected to continue declining gradually in all locations. However, because large volumes of water continue to come from the northern part of the basin, water levels along the main stem of the river are expected to remain generally high over the next week. The northern part of the basin will remain vulnerable to heavy rainfall events in the coming weeks; therefore, further increases in water levels from Mattawa to Lake Coulonge due to high spring runoff cannot be ruled out.