Sound probe

05 May 2017
Listening: Vancouver is trying to understand the impact of ship noise on at-risk whales. Credit: Vancouver Fraser Port Authority

Listening: Vancouver is trying to understand the impact of ship noise on at-risk whales. Credit: Vancouver Fraser Port Authority

Dave McIntyre examines the emerging trend to monitor underwater noise levels at ports

As if having to plan for berthing, cranes, marshalling space and hinterland connections is not enough for port management, a new trend emerging is to monitor underwater noise levels with either financial incentives - or possible costs - to reflect how well ship operators are keeping to prescribed targets.

The commercial realities of underwater noise pollution came home to roost late last year when the US National Fisheries Service required the Port of Gulfport to install a bubble curtain to prevent pile driving noise from harming fish and turtles. The device creates a wall of bubbles to reduce the impact of underwater sound waves.

At the heart of the issue is protection for at-risk marine life such as whales. Sound is critical for the survival of many marine animals. It's a primary means of communication, orientation and navigation, finding food, avoiding predators, and mate selection.

Most underwater noise from large vessels is caused by propeller cavitation. The noise interferes with the ability of marine animals to transmit and receive acoustic information.

Vancouver first

The Vancouver Fraser Port Authority is leading the way with its EcoAction initiative, an incentive programme for marine vessels. Since 2007, the EcoAction program has recognised a variety of fuel, technology and environmental management options that make ship operators eligible to receive discounted harbour dues.

This year, the authority added new incentive criteria to include harbour due rate discounts for quieter ships, making Canada the first country in the world with a marine noise reduction incentive.

The new criteria include three quiet-vessel ship classifications and three propeller technologies shown to reduce underwater noise. Ships obtain up to 47 per cent off the basic harbour due rate for meeting voluntary industry-best practices.

This follows research undertaken by the port authority-led Enhancing Cetacean Habitat and Observation (ECHO) program. Acoustic disturbance was identified by ECHO as one of the key threats to whales in this region.
To further understand impact of ship noise on at-risk whales, Vancouver Fraser Port Authority, with support from Transport Canada, the University of Victoria's Ocean Networks Canada and JASCO Applied Sciences, deployed a hydrophone listening station in the Strait of Georgia to monitor underwater vessel noise in 2015.

The station monitors and reports on ambient noise levels, marine mammal detections and passing vessel noise.

Deepsea vessels are manoeuvred over designated way-points in order to capture associated vessel noise accurately. Since 2015, more than 3,100 vessels have been measured by the hydrophone. This also allows for testing mitigation solutions, for example the cleaning of ship hulls to potentially reduce underwater noise.

Performance indicators

On the other side of Canada, Green Marine is adding performance indicators dealing with underwater noise from ports. Green Marine is a voluntary environmental certification program for the North American marine industry. Among the 38 ports currently participating in the program, 20 are Canadian and 18 American, including ports such as Halifax, New Orleans, Seattle and Gulfport.

To receive certification, participants must benchmark their annual environmental performance through the Green Marine environmental program's self-evaluation guides. They also need to have their results verified externally and agree to publication of their results.

The new indicators, which apply to shipowners and ports operating in salt water, encourage the maritime industry to manage underwater noise sources during ongoing activities, development/construction and/or port maintenance activities to reduce impacts to marine mammals.

Level 1 seeks to monitor regulations. Level 2 seeks to raise awareness of the problem, promoting the provision of marine mammal sightings data, understanding the zone of impact of activities, and using a trained marine mammal observer during port-related in-water construction.

Level 3 requires the adoption of an Underwater Noise Mitigation and Management Plan or offering a recognition program to shipowners for vessel noise reductions. Level 4 includes such targets as developing incentive programs for ship operators such as fee reductions.

Level 5 requires meeting reduction targets on underwater noise or demonstrating continuous improvement in implementing the Underwater Noise Mitigation and Management Plan.

Voluntary drive

The new underwater noise performance indicators will be optional during the first year of assessment in 2017, but will subsequently be mandatory to obtain Green Marine certification.

Executive director David Bolduc says underwater noise is being recognised as increasingly important by numerous national and international agencies. “It is important to underline that the maritime companies and ports that are certified by Green Marine have voluntarily accepted to adopt the new underwater noise evaluation criteria with no regulations obliging them to do so.

“These participants made the commitment to address the issue more easily. For others, it was a relatively new issue; they needed to learn about noise, its sources, its potential impacts, and the mitigation measures.
“The indicator is a great tool to help them understand underwater noise and, most importantly, address this emerging issue. [It] is the result of collaboration among the industry, environmental organisations, the scientific community, and government representatives. Two intensive years of research and discussions were necessary to develop the five-level criteria.”

While Green Marine is ahead of the curve on this emerging issue, it not linked with any upcoming regulations/grading scheme. As a voluntary initiative, participants willingly commit to go beyond regulations.

Broader scale

On a broader scale, research is going on internationally with the idea of producing parameters which ports will be able to follow.

The US National Oceanic and Atmospheric Administration (NOAA) has developed an Ocean Noise Strategy Roadmap, which looks at the effects of ocean noise on marine life.

The roadmap is intended to serve as a high-level guide, rather than a prescriptive listing of program-level actions. It summarises the status of the science to support the Ocean Noise Strategy's goals, details relevant NOAA management and science capacities, and recommends cross-agency actions that could be taken to achieve more comprehensive management of noise impacts.

A series of key goals and recommendations are presented to enhance NOAA's ability to manage both species and the places they inhabit in the context of a changing acoustic environment.

NOAA is already taking on some of these recommendations, such as the recent launch of an underwater network of acoustic monitoring sensors. The roadmap suggests key roles for continuing partnerships and starting new ones with other federal agencies, industries, academic researchers, environmental advocates and others.

“NOAA has the scientific and technical expertise to assess what's happening with ocean noise, help identify gaps in knowledge, and use various tools to alleviate or mitigate its effects,” says Richard Merrick, NOAA Fisheries' chief scientist.

Work on underwater noise is also progressing in the UK: The Centre for Environment, Fisheries and Aquaculture Science (Cefas) has teamed up with Marine Scotland Science and the University of Exeter to analyse underwater noise data from subsea sound recorders located around the UK coast.

For the first time, the team has drawn together measurements from around the UK coast to make an assessment of underwater noise pollution. They found many sites were exposed to persistent noise from shipping traffic.

Cefas is currently working in partnership with several UK universities to establish a permanent noise monitoring network, which will become operational in 2017.

The study will inform UK policy on underwater noise pollution, and forms the basis of the UK assessment of underwater noise under the EU Marine Strategy Framework Directive (MSFD), which assesses the status of European seas.



MAKING NOISE INCENTIVES WORK

A Vancouver port spokesperson tells Port Strategy that in 2016, a study identified a range of options that could be considered to receive incentives through its EcoAction Program.

After financial modelling and external stakeholder consultation, the authority selected three quiet notations from ship classification societies: Bureau Veritas, DNV-GL and RINA, and three cavitation and wake flow reduction technologies shown to reduce propeller-generated noise -- Propeller Boss Cap Fins (PBCF), Schneekluth duct and Becker Mewis duct.

The three quiet notations are eligible for a gold level – the highest - discount (47%) in harbour dues and the three cavitation and wake flow reduction technologies are eligible for a bronze level (23%) discount. Vessel operators, or their agents, provide a certificate of the quiet notations in order to qualify for the EcoAction incentive.

How receptive have ship operators been to these incentives? “We've heard anecdotally from some vessel sectors that they plan to upgrade their fleets to meet the new incentive standards,” says the port. “In the first quarter of 2017, two vessels have applied and been awarded a bronze level discount. VFPA hopes to see more vessels take advantage of this program throughout the upcoming months.”

This could be a benchmark for ports internationally to act on their underwater noise pollution levels.