Levels predicted to remain stable from Lac Coulonge to Lac Deschênes

Levels predicted to remain stable from Lac Coulonge to Lac Deschênes

The Ottawa River Regulation Planning Board has continued to publish daily updates on the levels and flows of the river throughout this spring freshet period. The latest update, from April 27, notes that while levels from snowpack in the lower portion of the basin may have peaked between April 21 and 23, depending on location, there still is plenty of water still to come down from the upper portion of the watershed.

“Additional spring runoff due to recent rainfall on the western and northern portions of the basin is slowing the rate of level decrease in downstream areas,” the statement reads. “From Mattawa down to Pembroke, levels are expected to continue rising today and tomorrow due to increasing outflow from reservoirs in the Abitibi-Timiskaming region, with minor flooding occurring in Pembroke. Between Lake Coulonge and Lake Deschenes, levels are expected to be fairly stable over the next few days.”

MRC Pontiac also published a press release yesterday from the Ministry of Public Security, giving an analysis of the effects of the rain expected this weekend and early next week.

“Until Sunday evening, the probability of 15mm of rain falling on the southern Outaouais is between 80% and 100%,” the statement reads. “From Sunday evening to Tuesday evening, considering that this is a rapidly changing system, the different models used by meteorologists show a great divergence in terms of quantity. While the European model tends towards total amounts of 15 to 25mm, the Canadian model predicts amounts between 30 and 60mm. It is therefore difficult to predict with any certainty the total amount expected. The high level of uncertainty, both in terms of quantities and the trajectory of this system, makes hydrometeorological forecasts very difficult and uncertain.”