Researchers find speed cuts don’t always protect belugas from ferry noise, as unique hull designs can complicate sound levels.
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East Coast Ferries
Canada’s East Coast has different ferry providers along the St. Lawrence River and Gulf, among the Maritime provinces, and around Newfoundland and Labrador. Several East Coast ferry routes pass through designated critical marine mammal habitat, such as that of Endangered belugas in the St. Lawrence and Saguenay Rivers and of Endangered North Atlantic right whales in the Gulf of St. Lawrence. Other at-risk whale species, such as blue, fin, minke and sperm whales, also frequent these waters. The “Quieter ferries in critical whale habitat on Canada’s East Coast” infographic displays route data gathered from the different ferry operators as well as critical habitat areas from map layers created by Fisheries and Oceans Canada and regulatory slowdown zones created by Transport Canada.
Characterization of the acoustic signatures of ferries operating in the summer habitat of the beluga population of the St. Lawrence Estuary
The University of Quebec in Outaouais (Université du Québec en Outaouais) undertook a Quiet Vessel Initiative project in partnership with ferry operator Société des Traversiers du Québec (STQ) that sought to characterize ferry noise in an area frequented by beluga near Gros-Cacouna – a deepwater port located in eastern Quebec on the St Lawrence River. For economic and operational reasons, Gros-Cacouna will become the home port of the Bas-Saint-Laurent ferry service in 2028. Led by researchers Clement Chion and Dominic Lagrois from the LISSÉ laboratory, this project includes measuring underwater noise generated from ferries and assessing the relative contribution from ferries to the overall noise levels in the St. Lawrence River using the 3MTSim simulator tool.
In fall 2023, the research team deployed a listening station on the seabed consisting of hydrophones positioned on metal tripods in shallow-to-intermediate waters approximately 6 km northeast of the port of Cacouna. The hydrophones were used to measure noise levels produced by ferries in the STQ fleet operating at speeds ranging from 8 to 15 knots in the St. Lawrence beluga habitat.
The results reveal that the ferries’ noise profiles do not align with generally accepted conventions for commercial vessels. The noise from the ferries did not consistently decrease with reductions in speed and in fact, travel at 14 knots was found to be quieter than at 8 knots for one of the vessels. The ferries assessed were of different sizes and configurations and had considerably different noise profiles. One finding relevant to ferry operational decisions was that the sudden acceleration of the ferry when departing the berth can negatively impact the marine environment, especially for marine species sensitive to low-frequency noise near the ferries’ berths.
Work on this project was supported by partners including Group for Research and Education on Marine Mammals (GREMM), Parks Canada, and Fisheries and Oceans Canada, and is ongoing. Alongside providing background data to assess noise risks in this critical beluga habitat, this project will also support the development of a new standard for assessing noise at the source of vessels operating in intermediate-depth environments.
Quieter Canadian Ferries Beyond the Quiet Vessel Initiative
While not part of the Quiet Vessel Initiative-funded projects, Marine Atlantic’s new ferry is a noteworthy Canadian initiative in advancing quiet ferry technology. Delivered in 2024, Marine Atlantic’s new passenger ferry, MV L’Ala’suinu, one of the Stena E-Flexer class of ferries, was designed to achieve Det Norske Veritas (DNV)’s “Silent-E” class notation. The notation recognises that underwater noise from the vessel is controlled to protect sensitive marine environments. Achieving a “Silent-E” class requires careful design and configuration of propulsion and onboard equipment to reduce noise while maintaining high efficiency.
What’s next for quieter ferries?
There is no single solution to reduce noise from ferries. Replacing ageing vessels at the end of their service life with quieter ones, retrofitting the noisiest vessels using a phased approach, and reducing noise through operational changes informed by noise monitoring, especially in critical habitat areas, all form part of the solution.
Embracing computer models and simulations will help ensure that new and retrofitted ferries run as quietly and efficiently as possible. Artificial intelligence is one area of development that is already showing promise for reaching these targets. For example, the European naval architecture community has developed a half-AI, half-simulation software that will automatically test design iterations to find an optimal design for a set of competing design targets.
In Canada, further research investment could support the development of such software for Canadian vessel operators. Continued collaborations between research institutions and the maritime industry, such as BC Ferries has undertaken with the University of Victoria, and greater data sharing of vessel design and operational details will help bolster these efforts.
This article was prepared by Clear Seas on behalf of Transport Canada as part of the Quiet Vessel Initiative and is part of a four-article series on ferries and underwater vessel noise.
Continue learning about the new discoveries and challenges in making vessels quieter with the other topics in this series here
The Quiet Vessel Initiative is a federally funded program through Transport Canada. Industry partners and researchers interested in potential research and development collaborations to advance innovative solutions in marine technology are invited to contact the Quiet Vessel Initiative team at Marine-RDD-maritime@tc.gc.ca.
Frequency: sound moves through a medium like water as a wave, thus the term sound wave. Frequency, also known as pitch, indicates how often a sound wave repeats within a single second. Measured in Hertz (Hz), also known as cycles per second, higher numbers signify higher-pitched sounds and lower numbers mean lower-pitched sounds.
