STEPHEN RICCIO
PONTAIC March 31, 2021
While the number of precipitation events is a major factor in whether flooding will be severe this spring, Hydro Québec and the Ottawa River Regulation Planning Board (ORRPB) say that signs are positive so far.
Given the onset of the spring freshet period, levels along the Ottawa River have begun to . . .
rise over the last week. Major rainfall events on both March 26 and March 28 added to those levels, with another significant event expected on March 31.
According to Hydro Québec engineer Annie Marcotte, the rain that falls at this time of year almost immediately runs into the river given how saturated the soil is.
With the snow having melted fairly rapidly, Marcotte said this is a good sign compared to past years.
“We had a good week of snow melt [last] week so there [are] a lot of regions in the southern part of the watershed where there is hardly any snow left, so that is really good,” she said.
Marcotte noted that one of the big factors for catastrophic flooding in 2019 was the continued dose of snow through March and in early April, which created a large amount of runoff.
According to a March 25 press release from the ORRPB, there could be some typical minor flooding in low-lying areas due to rising levels but overall, things look positive.
“While it is not possible to completely rule out the occurrence of a large spring freshet, the factors that are known at this time, namely below average snow water content in all locations and an early spring start, are positive indicators of a year without excessive flooding along the Ottawa River,” the release stated.
Both the release and Marcotte noted that while snow-water content is an important piece to the puzzle, there are other factors that influence the level of the spring freshet, mainly being upcoming snowfalls and rainfalls.
Marcotte said that while there is still some build-up of snow along northern areas of the river, reservoirs will be used to help maintain stable river levels once that snow melts.
