Fisheries and Oceans Canada has noted significant increases in the quantities of sediment removed from the harbors of the archipelago in recent years.
The overall volume of sediments mined has seen a staggering increase of 65% between 2020-2021 and 2022-2023, excluding statistics from ports that have been dredged only once in the interval.
At the Millerand wharf, the quantity of sand and gravel excavated has increased by 71% in two years. On the Pointe-Basse side, the increase is 24%, while this statistic rises to 13% in Grosse-Île.
There is an increase in dredging volumes. It depends on the harbors of course, but the general trend is really on the rise and we see that it is accelerating from year to year
says the Quebec director of the Small Craft Harbors Program of Fisheries and Oceans Canada, Boussaad Akrour.
” Silting up on the Magdalen Islands is our main issue in terms of dredging in Quebec. »
Although Mr. Akrour specifies that the increased silting phenomenon is also observed in the fishing ports of Gaspésie and the Maritimes, he is of the opinion that the situation in the Magdalen Islands is more problem
.
A hefty bill and a operational stress
Costs for dredging operations have increased from $2.2 million in 2019-20 to $3.3 million in 2021-2022.
Although the price of the work is strongly influenced by the volumes of sediment to be extracted, Fisheries and Oceans Canada points out that other significant elements enter into the equation, including the management of contaminated sediments that require special treatment.
In addition to considerably increasing the bill, the increase in the volume of sediment causes a race against time for the teams responsible for dredging, before the launching of the lobster traps.
It has operational impacts because with the absence of ice, the opening of the fishery is getting earlier and earlier, but on the other hand, we have large volumes of sediment to extract.
mentions Boussaad Akrour. So we end up dredging a larger amount of sediment in less time. It gives us stress in operational terms to finish in time for the start of the fishery.
Complete dredging of all Madelinot fishing harbors is simply impossible before the start of the season: spring operations are limited to clearing the entrance channel to the wharf to ensure the safe passage of boats.
A second phase of dredging, or even a third, is then planned during the summer to completely free the interior of the ports.
Climate change involved
Although it is still too early to fully understand the phenomenon of accelerating silting, the Quebec director of the Ports for small craft program clearly indicates that climate change is to blame.
” It is clear that climate change really contributes in large part to the phenomenon, it really affects the dynamics of sedimentation »
Before, the ice was really thicker and remained later in the spring, whereas now the banks are often bare in the face of waves and storms. It creates erosion, so we have more sedimentation that comes from the earth.
Mr. Akrour also points out that the extreme wind and storm phenomena
are more and more frequent and that these influence the sedimentary dynamics.
The orientation of harbors in relation to sea currents also has impacts
he adds.
A study in progress at Grande-Entrée
Fisheries and Oceans Canada has already launched a study to better understand theare phenomena causing increased silting and the solutions to consider. The Grande-Entrée harbor was chosen as the study site.
It’s a trend, we can’t sit back and watch volumes and budgets increase endlessly. It is clear that we must understand what is happening first and then look for solutions.
says Boussaad Akrour.
” These are quite special phenomena that we must understand in order to find long-term solutions. »
The latter specifies that a resource specializing in the field will look into sedimentary dynamics and try to target the causes using statistics, readings and measurements taken in the field.
We will look at all of this to better understand where it comes from. Then we can think about solution options, whether it’s engineering solutions on how to redesign our harbors when we’re going to rebuild them based on sedimentation
explains Mr. Akrour.
The departure of Madelinot lobster boats is scheduled for May 7. Fisheries and Oceans indicates that the spring dredging of all harbors should be completed on time, unless several days of bad weather change the situation.
Reference-ici.radio-canada.ca