The Société des traversiers du Québec plans to carry out, year after year, dredging and sediment disposal work in the critical habitat of the St. Lawrence beluga, not far from Cacouna. The government corporation will also carry out the operations at a time of year when females accompanied by their young are present in the sector. But she assures that all measures will be taken to reduce the impacts on this endangered population.
The Société des traversiers du Québec (STQ) manages the Rivière-du-Loup wharf, as part of the ferry service that connects this municipality to that of Saint-Siméon, in Charlevoix. However, the port area on the south shore of the St. Lawrence is subject to significant sedimentation, which forces the STQ to carry out annual sediment dredging work.
Nearly 60,000 cubic meters were thus removed in 2020, before being discharged into the estuary, in an area located three kilometers northeast of the wharf. According to what the STQ points out in a written response to questions from the Homework, the annual average, however, is around 42,000 cubic meters. “This requires nearly 450 sediment transports to the authorized drop zone,” it says.
In order to continue these annual dredging operations, the STQ wishes to obtain an authorization from the Quebec Ministry of the Environment which would be valid for the next ten years. The impact study is currently being analyzed by the ministry, as part of a process that could lead to a review by the Bureau d’audiences publiques sur l’environnement.
Females and young belugas
In its impact study, the state-owned company recognizes that “the work area is located in the critical habitat of the beluga”. According to expert advice from Fisheries and Oceans Canada (DFO), this region of the estuary is even considered a critical zone for “the most vulnerable segment of the population”, namely females and their young. The Cacouna sector, located nearby, is particularly recognized as a real nursery for the species, which has been experiencing significant reproduction problems for several years.
However, dredging work poses real risks for belugas, according to what emerges from the STQ’s impact study. “The noise caused by the works could affect their communication, as well as induce behavioral changes and population displacements. The risks of collisions, [les matières en suspension] and food availability could also affect these populations,” the 246-page document reads. It also emphasizes that “the disturbances caused by noise as well as anthropogenic disturbances are among the main threats to the beluga”.
In order to reduce the risks, the STQ says it wants to avoid carrying out the work, lasting four to six weeks, during “the period of intensive attendance”, which it places from mid-April to September 30. From that date, operations could take place 24 hours a day. The Crown corporation, however, specifies that a request for a “permit” is made each year, under the Species at Risk Act (SARA) of the federal government. This request is necessary to obtain authorization to begin work on September 20.
Are female belugas and their young still present in the sector in September and October? The question is all the more relevant since SARA has prohibited since 2017 any activity that would have the effect of “destroying” an element of the beluga’s critical habitat.
According to what can be read in the impact study filed with the Quebec Ministry of the Environment, the beluga would leave the work area “towards the end of September”. A notice from experts on the species published in 2016 by Fisheries and Oceans Canada, however, states that females and young would be present until October. “The moment of the abandonment of the sector in the fall” is uncertain, indicates this opinion, citing scientific work which testifies to the presence of the species “until the end of October or November”. By way of comparison, speed limit measures in the Saguenay–St. Lawrence Marine Park are in effect until October 31, specifically to protect belugas.
Monitoring
In a written response to questions from the Homework, the STQ also recognizes that the work will take place while belugas will still be present in the area and that they could, therefore, lead to a “disturbance” of the habitat. But she adds that the work could not take place later in the fall, for reasons of staff safety.
The Société des traversiers du Québec therefore promises “surveillance” within a radius of 400 meters and the interruption of work, which can take place day or night, if a beluga approaches within 400 meters. This “program”, approved by Fisheries and Oceans Canada, is put in place “to minimize the impacts of work on the species”.
The dredging project in Rivière-du-Loup will not be the only one to continue in the next decade in this sensitive habitat for the beluga. The Société port du Bas-Saint-Laurent et de la Gaspésie, which manages the port of Gros-Cacouna on behalf of the Quebec government, has also submitted a dredging project which is undergoing an environmental assessment. However, the work will only be carried out from 1er November, since the belugas are then “very few present in the Cacouna sector”, we specify by email.
DFO experts have already pointed out that, for the dredging in Cacouna and Rivière-du-Loup, “land disposal of sediments would be desirable” in order to eliminate habitat loss for the beluga. This option was not retained, since the sediments will indeed be discharged directly into the habitat of the species.