Forecasts for 2025-05-05

River conditions forecasts posted on 2025-05-05 by Ottawa River Regulating Committee

Spring runoff in the northern part of the basin remains very high. Reservoirs throughout the basin are being used to store runoff and reduce flooding as much as possible. Minor flood levels have been reached in most flood prone locations between Mattawa and Lake Deschenes. Levels may reach or exceed the major flood level in Mattawa and from Lake Coulonge down to Lake Deschenes depending on the amount and location of upcoming rainfall Tuesday and Wednesday. From Gatineau (Hull Marina) down to Hawkesbury / Grenville, 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. Uncertain weather and hydrological factors play into estimating peak levels. On May 5, peak level estimates are: Mattawa (154.65 m), Pembroke (113 m), Lac Coulonge (108.3 m), Chats Lake (75.3 m), Lake Deschenes (59.95 m), Gatineau -Hull marina (43.8 m) and Thurso (42.40 m).