Ottawa River Regulation Planning Board

Flows and water levels on the main stem of the Ottawa River continue to rise due to increased runoff from ongoing rainfall combined with snowmelt from the mountainous areas of the basin. Minor flood levels have been reached in Pembroke, Lake Coulonge and Britannia, and should be reached in Mattawa and Chats Lake on Thursday. Levels may reach or exceed the major flood level from Lake Coulonge to Lake Deschenes depending on the rapidity of snowmelt and precipitation amount received today. From Gatineau (Hull Marina) down to the Montreal Region, levels are expected to exceed minor flood levels but should remain below major flood levels. Our website Forecasts section provides expected water levels over a four-day horizon in your area. Levels are expected to peak starting Thursday-Friday between Lake Coulonge and Lake Deschenes, and starting Saturday from Gatineau down to the Montreal Region. Uncertain weather factors play into estimating peak levels. On April 29 peak level estimates are: Pembroke (113.15 m), Lac Coulonge (108.40 m), Chats Lake (75.45 m), Lake Deschenes (60.05 m), Gatineau -Hull marina (44.00 m) and Thurso (42.60 m).