2015_3 follow in my wake master

Follow in my wake

With its growing clout, the cruise industry can help spread environmental sensitivity across the globe. With technology and enforcement – Ocean Rangers now patrol Alaskan ships to make sure waste and effluent don’t reach the sea – cruises can head the green fleet.


The stunning landscapes of Alaska attracted almost a million cruise ship passengers in 2014; the state is also second only to Las Vegas as a domestic tourism destination. Industry group Cruise Lines International Association (CLIA) estimates that the ships have helped create one in 13 jobs in the most northern American state. And as 22% of passengers who cross the Gulf of Alaska also set aside time to travel inland, the industry’s importance to the state can hardly be understated. 

In 2015, Alaska entered the last phase in its transition to a sulphur emissions control area (SECA) – considered an ambitious enforcement of pre-existing regulations of the 2009 marine-pollution convention, MARPOL. 

The cruise industry had expressed worry about the costly upgrade of bunker fuel. The operators got backup from many local entrepreneurs who worried that SECA could impact consumer habits – passengers who face more expensive tickets are likely to spend less cash on shore – but the new regulation was upheld in court in 2013. 

Switching to low-emissions LNG can be an option for certain vessels, while scrubbers can reduce sulphur emissions from the exhaust. Significantly, MARPOL, which is an International Maritime Organization (IMO) convention, does not simply aim to protect the air but also the water. 

“It regulates oil and oily wastes, noxious liquid substances, harmful substances in packaged form, sewage, garbage and certain deleterious air emissions,” explains John Kaltenstein, a marine policy analyst at Friends of the Earth U.S.

When it comes to solid waste, a tally by Lloyd’s Register shows that nature has little talent for dealing with man-made objects. It takes two to four weeks for a paper bus ticket to dissolve in the sea, for example. Cotton cloth, such as clothing or even a towel, takes one to five months. Painted wood won’t degrade unless it spends 13 years in the water. Plastic could well be the worst offender; the currents and the waves need 450 years to break down a plastic bottle. 

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Fluid waste is no less of a problem, and key areas of concern are the effective monitoring and processing of black water (sewage), grey water (effluent from kitchens, laundries – areas without faecal contamination) and oily water (bilge water from the engine rooms onboard large vessels). 

“The vast majority of the cruise ship operators are very particular about not only meeting legislative requirements but exceeding them,” says Kevin Robertson, Wärtsilä Water Systems General Manager.

Robertson and his colleague Wei Chen, Head of R&D at Wärtsilä Water Systems, point out that industry leadership and enforcement both play important roles. The Alaskan authorities, for example, now have Ocean Rangers onboard cruise liners who keep tabs on the ships’ compliance with state and federal requirements regarding marine discharge and pollution. 

 “For the technologies to serve their purpose of actually protecting the environment, the regulations should have better enforcement schemes. We start to see this in Alaska,” says Chen.

It was the Alaskan authorities – who live with the painful memory of Exxon Valdez – that first grasped the nettle of marine pollution with real determination. In 2000, the new Commercial Passenger Vessel Environmental Compliance programme (CPVEC) became the only independent monitoring and sampling system in the global marine industry at the time.

That same year, working with cruise operators, Wärtsilä developed a new generation of Advanced Wastewater Treatment (AWT) systems. An Alaska Cruise Ship Initiative Report estimated in 2000 that a typical large cruise ship generates an average of 8,434 litres of oily bilge water during 24 hours of operation. An advanced oily water separator (OWS), such as Wärtsilä’s, can treat up to 5 m3 of bilge water each hour. The OWS is thus capable of guaranteeing a maximum oil content in the effluent of 5 ppm (parts per million), such a low level that it clears with bravura the 15 ppm limit set by MARPOL.

Grey water is also a serious area of concern. More than 3 million litres are typically produced on a seven-to-10-day cruise, making it the industry’s largest source of liquid waste.

Along with black water (30,000 to 79,000 litres per day), grey water has to be efficiently managed. The Wärtsilä Hamworthy Membrane BioReactor uses a natural biodegradation process free from harmful chemicals or UV to render the grey and black wastewater harmless before the ship discharges it. During this process, harmful phosphates and nutrients are also greatly reduced. 

Despite the availability of trustworthy technology, incidents of pollution and even malpractice still have made headlines. The sinister nickname “magic pipes” refers to the practice of piping pollutants directly into the ocean.

In 2004, a vessel released 20,000 gallons of untreated sewage into the harbour of Juneau, the Alaskan capital. It lead to the maximum USD 200,000 fine, and the operator paid an additional USD 500,000 to the non-profit National Forest Foundation, agreed to community service and spent a further USD 1.3 million on implementing an internal compliance plan that included training its staff.

What happens in Alaska and other regions with environmental controls will have a significant and positive spill-over effect worldwide, argues Robertson.

“The cruise industry is the fastest-growing leisure activity in the world. The single biggest market for the cruise sector to grow into is China,” he says. “They will take those standards into every market they go.”


Waste water management

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