SUSTAINABILITY

CONSTRUCTION EFFECT ON MARINE LIFE

WHEN WE TALK ABOUT CONSTRUCTION, WE HEAR PROGRESS BEING MADE, BUT WHAT DOES IT SOUND LIKE TO MARINE LIFE?

UMAH GANESHALINGAM MENG, MSC PROJECT MANAGER AT TURNER & TOWNSEND, UN VOLUNTEER WITH A BACKGROUND IN AUDIOLOGY

Images courtesy of Oman / The Ocean Agency

Glacial ice sheets were a natural acoustic refuge for marine mammals such as whales and dolphins. With water temperatures on the rise, these cetaceans are already under threat, but there is also a ‘silent killer’ on the loose.

With the rapid melting of the ice sheets forcing marine mammals such as whitebeaked dolphins to leave their expanse causing loss of species as it tips the biodiversity balance, noise pollution, a lesser-known threat, is now on the rise and similarly threatens the biodiversity of our oceans.

Many aquatic and terrestrial species use sound to communicate, find prey, avoid predators, mate and navigate their way around the great blue sea. This echolocation process is crucial to their existence, yet interference from noise pollution is causing marine life to lose their way and starve to death.

Cetaceans have strong herding instincts. Whales for example, often refuse to leave a member of their pod behind if they are sick or jeopardised. In efforts to support a distressed member, a whole pod could strand themselves, despite human intervention to push them back out to sea.

Regrettably, anthropogenic noise produced from the construction industry is increasingly being linked to cetacean strandings all over the world.

According to the US Environmental Protection Agency, sounds below 70 dBA (decibels) are considered safe. In construction, our activities are often deafening, even to us!

Welding averages at around 100 dBA, impact guns used in oil and gas exploration are approximately 120dBA, and sonar used in submarine navigation and communication, measures a whooping 235dB in water, which can cause internal haemorrhaging.

A 2020 study found a strong association between both sonar used in military exercises and ocean exploration, and the death of beaked whales.

If we don’t want scuba diving and coral reefs to be a thing of the past, we need to take action to minimise our noise footprint now! Reducing our noise pollution. The UAE’s Net Zero by 2050 strategic initiative visualises a green future, it is a mammoth undertaking and focuses on a holistic approach to investing 600 billion dirhams in clean and renewable energy. But are we proposing the right solutions?

For example, offshore wind farms may not be the silver bullet we thought it to be. Its operation is quiet, however, the construction is not. Current construction methods use piling, drilling and dredging to anchor the monopole wind turbines to the ocean floor. …And what about noise we make indirectly, are we factoring the supply chain into our sustainability plans? Shipping cargo for example, produces loud noise that is at the same low frequencies used in the songs of male whales. With increasing demands for construction material due to the rise of mega programmes, are we taking into consideration the additional threat that shipping activities pose to the survival of our marine life?

With the UAE hosting COP 28, I hope to see noise pollution on the agenda. There’s a need for investment in a sound observatory to; research sound-related data capture, monitor noise pollution, and develop more stringent noise regulations.

Act now Outlined below are steps we can take to play our part in protecting our sea life.

> Short term: we can immediately make a difference by carrying out risk assessments on our sites, recording sound levels during construction activities, and by using sound barriers and bubble curtains to attenuate sound.

> Medium term: Mega programmes need noise impact assessments and noise reduction strategies. Major programmes should also consider bringing in programme advisory consultants to implement noise strategies and explore innovative practice and construction methods.

> Long term: Not only do we need to build quietly, we also need to influence our supply chains to also take a greener approach in their own activities. If cargo ships were to reduce speeds by just six knots, the noise intensity would be halved! Designated marine protected areas are also necessary, with the added advantage of keeping tourism alive for decades to come.