Winning the fight against marine pollution

January 6, 2021

Unless you live, work or spend your leisure time on or beside the sea or a river, these bodies or water can be easy to ignore. It might be nice to take a walk along the river or spend a day at the beach, but beyond that, you may barely think about them at all. Even if you’re concerned about climate change and the environment, your focus might be on urban issues such as electric cars, emission-free zones, solar panels for your roof and trying to ‘buy local’.


But the health of our oceans and waterways has a bigger impact on our planet, our environment and therefore, our lives, than you might think.


Why are clean, healthy rivers and oceans important?


Water covers 70% of the Earth’s surface. But it’s not just a surface entity; it has depth, and when its volume is factored in, we find water provides 99% of the habitable space on this planet. Suddenly, we begin to get a sense of why it might be important.


Living in that habitable space, we find phytoplankton: microscopic plants that cover vast areas of the ocean, especially near the nutrient-rich coasts, and which also exist, to a lesser extent, in freshwater rivers and streams. Why should we care about that?


Firstly, phytoplankton is an important part of the marine food chain, providing nutrition and energy up the chain to eventually feed the ocean’s largest residents, such as whale sharks. Of course, within that food chain are the fish and seafood species we eat. Nearly half of the world’s population—around 3.1 billion people—are estimated to rely on fish for 20% of their daily protein intake, and that rises to over 70% in some coastal communities.


And secondly, while the Amazon Rainforest is often called ‘the lungs of the world’—lungs that are, incidentally, getting smaller and less healthy at an alarming rate—that’s a title water deserves too.


Peter Thomson, the UN Special Envoy for the Ocean, famously said, “Every second breath of oxygen that we take comes from oxygen produced by life in the ocean.”


That’s no exaggeration. Water provides more than half of the oxygen we breathe, and it does so mainly thanks to phytoplankton, which, just like plants on land, produces oxygen. But also just like land plants, phytoplankton needs light, so it struggles to survive in murky, polluted waters.




Clean water is vital for our basic survival.


Water is also a major climate control component and prevents the wildly fluctuating climate conditions we observe on other planets. How does it do that? Well, water absorbs over 90% of the heat that enters our atmosphere. Without it, our planet wouldn’t be habitable. Our separate ‘seas’ and ‘oceans’ are really just one big ocean; it’s estimated that over the course of around 1,000 years, a water molecule travels around the whole world.


The thermohaline conveyor belt, which connects deepwater currents to surface currents, distributes nutrients, food, and marine life around the world, and transfers heat from the equator to the poles. But obviously, this is a delicate balance easily disrupted by environmental changes and extra heat. Ocean warming, if left to continue, may affect this process, and it’s already affecting the distribution, population size, food chains and habitats of some species. The ocean also produces ingredients that we’ve used to develop medications to tackle cancer, Alzheimer’s and heart disease, as well as painkillers.


Clean water is vital for a stable climate, a habitable planet and a marine ecosystem that provides what we need.


Finally, not only do our oceans and rivers provide a transport medium for a huge portion of global trade, but also a medium for a host of recreational activities, both on the water, under the water, and on their coasts and banks. These recreational pursuits are vital for our economy. Our seas and waterways support a global tourism industry worth an estimated £8 billion and watersports continue to grow in popularity.


However, polluted water poses risks to human life as well as marine life. When Surfrider Europe surveyed its blue community in 2019 and 2020, two out of five respondents said they had already suffered health impacts from spending time in the water, and recently, a new environmental report released by ocean conservation charity Surfers Against Sewage (SAS) revealed that water companies are routinely discharging untreated sewage into UK waters. The charity said that they had had 153 health reports submitted by water users who had fallen ill after being in the water. There’s also been a worrying rise in antibiotic-resistant organisms found in the digestive tracts of swimmers. If our waters are no longer seen as a safe place to spend our time, people will turn away from aquatic activities and look elsewhere for opportunities for recreation and exercise.


Clean water is vital for our leisure and tourism industries and our economy.



As Europe ground to a halt during the first Covid-19 lockdown, the media began to fill with stories of reduced pollution and increased wildlife in urban areas, and soon after, the positive effects on oceans and waterways too. With cruise ships in dock and a general reduction in marine traffic, the seas and rivers were not only less polluted by fossil fuel engine emissions, but less disturbed by marine traffic, resulting in less sediment churn from the seabed and clearer waters. This allowed more light to reach underwater plant life, vital to the aquatic food chain. The ESA's the Copernicus Sentinel-2 captured pictures of the deserted, clear waters of Venice where the waters were clearer than they had been in 60 years and marine life was once again visible. Imagine a world where these world-famous waterways always look like that.

IMAGE: contains modified Copernicus Sentinel data (2019-20), processed by ESA, CC BY-SA 3.0 IGO

IMAGE: Peter Ma

What’s causing water pollution?


Sadly, many of the things we do while using or enjoying our seas and waterways can cause an issue for the underwater world. Aquatic plants and animals have specific requirements for light, temperature, oxygenation, pH level and nutrient balance, so anything that upsets these variables can cause these organisms to suffer—and the minute one part of the chain is affected, a domino effect can cause repercussions throughout the whole marine ecosystem.


First, let’s quickly consider the polluters that we, as individuals, can do little about unless we’re in positions of power in the related industries. These include agricultural run-off (toxic pesticides, and fertilisers that may dump nutrients, damaging the aquatic balance), industrial run-off of heavy metals and numerous other toxic chemicals, oil spillage and particulates. Untreated sewage still has problems too. It often contains hydrophobic compounds that bind with the sediment on the sea floor. There are also several diseases shared between aquatic animals and humans. These can contaminate sediment and the creatures that live within it can become ‘disease reservoirs’, leading to accumulation in fish and the passing of the disease up the food chain to humans.


There are also the multiple types of pollution caused by freight shipping and cruise boats. According to the EU, maritime transport is responsible for about 2.5% of global greenhouse gas emissions. Cargo vessels emit sulphur and nitrogen oxides, particulate matter, and carbon dioxide. Even though they’re fuel-efficient, 80% of them use carbon-intensive heavy fuel oil.


And cruise vessels have similar issues.



IMAGE: Robert Ashley

With aeroplanes portrayed as the Big Bad Wolf of green travel, you might think cruises are a much eco-friendlier way to see the world. However, cruise ships aren’t the gentle ‘green’ giants you may believe they are.


“These ships usually operate close to the coast with long port calls at major tourist destinations,” points out a 2019 report by sustainable transport group Transport & Environment, which raises concerns about the large amounts of sulphur oxide (SOx) and nitrogen oxide (NOx) cruise ships produce. Both can cause serious health risks and acidification on land and at sea.


The report looked at emissions from various cruise companies, including the Carnival Corporation, the world’s largest cruise operator. It found that in 2017, around European coasts, Carnival's ships emitted nearly 10 times more SOx than all of Europe's 260 million cars. Even in sulphur emission control areas (SECAs) like Denmark’s coasts, air pollution from cruise ships is still unacceptably high, and Barcelona, Palma Mallorca and Venice were named as the most polluted ports.


However, these gases aren’t the only issue. Many cruise ships use heavy, toxic fuel and produce vast quantities of dangerous, ultra-fine particulates. They also produce a huge amount of waste, including plastics and sewage, that’s sometimes dumped in the ocean. Last year, the Carnival Corporation and its subsidiary, Princess Cruise Lines, were fined $20 million for environmental violations, including dumping plastic waste—just the latest in its long list of environmental crimes, which includes falsifying records to conceal violations. But many other cruise lines have faced fines too.


So, what can be done?


Under International Maritime Organization (IMO) rules, as of 1st January 2020, all international vessels have to use lower sulphur fuel, with some cruise lines also installing scrubbers. But this isn’t enough. Tougher, consistent environmental controls need to be introduced in line with what’s happening on land, and more ports need to take a stand, limiting cruise ship numbers, providing green electricity and setting their own standards to ban the worst environmental offenders. And we need a greener way to power these floating cities.


But which types of polluters can we take direct action on?


Well, atmospheric pollution caused by land-based activities is a significant polluter of the marine environment, as is the huge microplastics problem, and these are things we can help to prevent. However, the main polluter we have control over is our use, on our waterways and in the sea, of the ICE: the internal combustion engine.




IMAGE: Alfplant

The Culprit We Can Catch: The I.C.E.


You may think that the pollution caused by private boats, jet skis, jet boards and other motorised watersports is just, if you’ll excuse the pun, a drop in the ocean compared to environmental disasters like oil spills. But that’s far from the case.


Gary Fooks, a researcher and adviser to governments and industry and chairman of the Blue Sky Alliance to promote low emission engines, has worked for years to bring people’s attention to the damaged caused by old two-stroke engines. He compared the fuss made when a ship hit by Cyclone Hamish in 2009 dumped 250 tonnes of oil in Australia’s Moreton Bay—sparking a huge, headline-grabbing clean-up mission—to the scant attention paid to the 3000 tonnes of fuel and oil dumped into South-East Queensland waterways each year by weekend boating. He points out that because outboard exhaust pipes are under the water, they contaminate the water before contaminating the air, too, as the toxic gases they produce bubble up.


Emissions testing done by the US Environmental Protection Agency (US EPA) found that one hour of boat operation, even with a relatively ‘clean‘ engine meeting EPA 2006 regulations, produced the same pollution as about 50 cars at a similar ground speed. Older outboard engines that weren’t compliant with those regulations could emit around 10 times more pollution than compliant ones—the equivalent of 500 cars! The International Water Ski Foundation also estimates that pre-1997 two-stroke engines deposit around 30% of their partially burned fuel in the water.


There’s a direct relationship, too, between CO2 production and fuel use, so older, less-efficient outboards that guzzle fuel also produce far more CO2—one of the culprits causing water acidification. Our best estimates are that the average pH of the ocean has dropped from 8.25 in pre-industrial times (pre-1800) to 8.14, which may not sound very much until you consider that pH is measured on a logarithmic scale; this 0.1 represents a 30% increase in acidity. Shellfish (scallops, oysters, whelks), crustaceans (crabs and lobsters), and echinoderms (starfish, sea urchins) are among the groups most vulnerable to ocean acidification. Many of these species are not just of great commercial and consumable value, but also play key ecological roles in the ocean.


Internal combustion engines are also a lot noisier and smellier than electric engines, which makes them far more disruptive and damaging to both underwater creatures and those that make their homes or nests on coasts, lakeside areas and riverbanks.


Aside from the issues caused by ICEs, the chemicals used to clean, protect, and run watercraft often leach into the water and cause problems too. Detergents, paints, petroleum products, batteries and antifreeze can all contain toxins and metals that have a disastrous effect on water and its wildlife.


IMAGE: Solbian

The Pollution Solutions


Research into ways to use sustainable sources to supply some of the energy needed by freight ships is underway, but many of these vessels are massive, with huge energy requirements. However, the Organization for Economic Cooperation and Development predicts that with new technology, alternative fuels and renewable energy sources, the industry could be using carbon-free fuel by 2035. Companies working on this include:


  • Methanex, which produces cost-effective marine-grade methanol from renewable sources, reducing emissions of sulphur oxides (SOx) by 99%, nitrogen oxides (NOx) by 60%, and particulate matter by 95%.
  • IPCO Power, whose FID Injector creates a stable water in fuel emulsion—a higher efficiency fuel with reduced NOx, HC, and PM pollutants
  • Eco Marine Power, looking for innovative ways to replace fuel consuming engines with solar and wind power, which has already designed a system expected to cut emissions by up to 10%, (equivalent around four tonnes of fuel saved every day on a large cargo ship).


Large cargo ships also discharge ballast water, bilge water, grey water, and black water, all of which can decrease negatively impact aquatic environments and human health. Again, firms are working to tackle this: Alfa Laval’s ‘PureBilge’ is a high-speed centrifugal oily water separator, Genoil’s ‘Crystal Sea Separator’ requires no filter or maintenance and can even be used for fuel spills, and Wartsila’s ‘Super Trident’ system offers safe and effective sewage treatment at sea.


But if you’re asking yourself what you can do to limit river and ocean pollution, let’s look at where your actions can make a significant difference.




IMAGE: Lampuga GmbH

Making a Difference


You can live a greener lifestyle on land, buying organic produce to help change farming practices and lessen the outflow of harmful pesticides and fertilisers, eliminating plastics from our lives as much as possible and choosing more sustainable ways to travel, eat and live.


However, the major way in which you can positively influence the marine environment is to make sure that when you use rivers and the sea for recreation, you do so responsibly—and without the help of an internal combustion engine. You can try to avoid driving your fossil-fuelled car to the beach, throw away your litter and avoid the use of single-use plastics while you’re there. But even more importantly, you can look for the companies that rent electric jet skis and jetboards. You can choose to take the river cruises that are on electric boats. And if you’re buying boats, jetboards, jet skis or any other powered watersports equipment, you can go for the greener options, buying electric jetboards like those produced by Lampuga, exploring electric outboard motors from companies like ePropulsion, adding a solar power source by investing in Solbian solar panels or harnessing wind power via an efficient marine wind turbine, such as those sold by Leading Edge. In this issue, we’ve looked in detail at how these innovative companies are making a difference to the watersports industry, sustainable energy technology and the marine environment.



IMAGE: Felix Brönnimann

Electric propulsion and a greener future


Electric propulsion is a disruptive and positive technology that’s increasing in efficiency and performance all the time, while reducing in cost as more people adopt it.


Electric engines don’t leak fuel or oil. They require less maintenance than internal combustion engines and have a longer life. They don’t emit greenhouse gases, or toxic gases, liquids or particulates into either the air or the water, and they are much, much quieter than a conventional engine. They’re also cheaper to run, and often run for longer than a conventional engine on a full tank, too. This makes them kinder to humans, aquatic environments and the planet as a whole. So why isn’t everyone using them?


Due to the cost of boats and personal watercraft, purchasers of boats, jet skis and jet boards tend to be among the wealthier members of society. Simple socioeconomics means that many of them are therefore likely to be well-educated, and so more environmentally aware. But this environmental awareness must extend to our lakes, rivers and seas. Solar panels on our roof and an electric car on our drive are important and commendable commitments to sustainability, but as we’ve seen, the health of humans and the health of our planet are indivisible from the health of our oceans and waterways. It’s vital we don’t just look inwards to our polluted cities, but outwards, too, towards our oceans and waterways. Otherwise, there’s a real danger that the very environment and nature that watersports allow us to enjoy up-close will be destroyed forever.

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