Forecast for 2023-05-02

River conditions forecasts posted on 2023-05-02 by Ottawa River Regulating Committee

Flows and levels on the Ottawa River continue to rise due to increased runoff from significant rainfall over the entire basin received over the last few days. Levels are expected to peak in all locations on Wednesday or Thursday from Mattawa down to Chats Lake, and on Thursday or Friday from Lake Deschenes down to the Hawkesbury / Grenville area. Levels should remain 40 cm to 70 cm below the historical levels of  2019 (correction: 10-15 cm below at Pembroke) depending on locations. Levels in Mattawa and Pembroke are now expected to slightly exceed the major flood threshold. Levels are above major flood threshold in Lake Coulonge since April 19 and are expected to exceed that threshold in Chats Lake and Lake Deschenes today. Please refer to the forecast section of our website for more information about the expected peak levels. Between Ottawa/Gatineau and the Hawkesbury / Grenville area, levels are expected to exceed the major flooding thresholds starting today in flood prone areas. The major flood threshold is defined as the level at which one or several streets are beginning to flood, with several houses/buildings or neighbourhoods being affected.