Cruise Ships: Polluting The Ocean's Depths

Cruise ships are a major source of ocean pollution, with a recent study finding that a quarter of all ocean waste comes from cruise ships. Cruise ships dump sewage, food waste, oily wastewater, solid waste, scrubber wastewater, and gray water from sinks, showers, and laundry facilities directly into the ocean. This waste is filled with toxins, bacteria, chemicals, heavy metals, and oily waste, which has a devastating impact on marine wildlife, coral reefs, and the marine ecosystem. In addition to water pollution, cruise ships also contribute to air and noise pollution, with their idling diesel engines emitting high levels of sulphur oxides and nitrogen oxide. The environmental impact of the cruise industry is far-reaching, and new laws and standards are urgently needed to regulate their polluting practices.

Cruise ships dump sewage and greywater into the ocean

Cruise ships generate a range of waste, including solid waste, oily bilge water, scrubber wastewater, sewage, and greywater. While it is against US and international maritime law to release garbage and plastic waste directly into the water, many cruise ships have done so anyway. Carnival Cruise Lines, for instance, was caught dumping food mixed with plastic waste into the waters of the Bahamas, while Royal Caribbean was fined $20 million for its illegal plastic disposal methods.

Cruise ships also dump sewage and greywater into the ocean. Greywater refers to wastewater from sources such as showers, sinks, and laundry facilities that do not contain fecal contamination. Blackwater or sewage, on the other hand, refers to wastewater with fecal contamination. An average-sized cruise ship produces 30,000 gallons of sewage and 255,000 gallons of greywater every day. While US law requires cruise ships to treat waste within 3 to 3.5 miles of the shore, beyond this distance, there are no restrictions on dumping polluted sewage and greywater.

The sewage dumped by cruise ships contains not only human waste but also chemicals, pharmaceuticals, bacteria, viruses, and heavy metals that are harmful to marine life and ecosystems. Greywater can also be highly polluted and contribute to environmental damage. The discharge of sewage and greywater by cruise ships has led to toxic algae blooms, dead zones, and toxic water bodies worldwide, causing wildlife deaths and hurting coastal communities.

The cruise industry has been criticized for its waste management practices, and there have been calls for stronger regulations and the adoption of state-of-the-art sewage treatment technology. While some cruise lines have implemented new technology on ships cruising in Alaskan waters, where higher state standards are required, there is a push for all oceans to be protected. Upgrading waste treatment facilities and adopting new technology can help reduce the pollution caused by sewage and greywater dumping, improving the health of oceans and marine life.

Cruise ships emit sulphur oxides, nitrogen oxide, and other harmful gases

Cruise ships emit sulphur oxides, nitrogen oxides, and other harmful gases, causing air pollution and contributing to global warming. Sulphur dioxide, a key component of acid rain, causes respiratory and cardiovascular problems. In 2019, an air monitoring study in Skagway, Alaska, found levels of nitrogen oxide, an ingredient in smog, to be five to ten times higher than at other sites in the state with fewer cruise ships.

The use of heavy fuel oil, one of the dirtiest fossil fuels available, is a significant contributor to these emissions. Cruise ships burn an estimated 150 tons of this fuel per day, releasing dangerous levels of sulphur and heavy metals into the atmosphere. In addition to air pollution, the burning of heavy fuel oil also impacts the ocean. To comply with regulations requiring the use of low-sulphur fuel, some ships install scrubbers, which work by spraying seawater into the exhaust pipes to reduce sulphur emissions. However, this process creates acidic wastewater that is then pumped back into the ocean, altering its chemical balance.

Cruise ships also emit nitrogen oxides, which are released into the air and contribute to smog formation, as seen in the Skagway study. These emissions can have serious public health implications and impact fragile habitats and species. Venice, for example, saw an 80% reduction in sulphur emissions after implementing a ban on large cruise ships in 2021.

To reduce emissions, ships could lower their speed, as emissions are estimated to decrease by up to 24% with reduced speed. Implementing electrical connections in ports, as done in Hamburg, Rostock, and Kiel, can also reduce air pollution and greenhouse gas emissions.

Cruise ships produce solid waste and oily bilge water

Cruise ships produce a large volume of solid waste, including paper, food waste, glass, and plastic. They also generate oily bilge water, which is water mixed with oily fluids such as grease, lubricants, and other wastes from mechanical sources like engines. These wastes are filled with toxins, bacteria, chemicals, heavy metals, and oily residues.

Oily bilge water is a significant source of ocean pollution, as it is often discharged into the ocean, altering its chemical balance. Vessels are required to maintain an Oil Record Book to record the disposal of oily residues and the discharge of bilge water. However, there have been numerous confirmed cases of illegal discharges of oil and oil-based products by cruise ships, ranging from a few drops to hundreds of gallons.

Solid waste and oily bilge water from cruise ships can have detrimental effects on marine life and ecosystems. The waste dumped into the ocean can impact the food, migration patterns, and overall health of marine wildlife. Additionally, the increased waste contributes to the problem of pollution and oxygen depletion in the waters, further threatening aquatic life.

Cruise ships' solid waste and oily bilge water also affect coastal communities. The destruction of coral reefs, which provide shelter for a quarter of marine species, disrupts fishing grounds and vital habitats. The discharge of untreated waste and the use of anchors by cruise ships further compound the issues, causing irreparable damage to sensitive ocean ecosystems.

While some cruise lines have implemented policies to reduce waste and increase recycling, there is a need for stricter regulations and enforcement to address the pollution caused by solid waste and oily bilge water from cruise ships. The environmental impact of the cruise industry highlights the urgency for sustainable practices and the protection of marine environments and communities reliant on healthy oceans.

Cruise ships destroy coral reefs with their anchors

Cruise ships have been found to contribute to the destruction of coral reefs, which shelter one-fourth of marine species globally. This destruction is caused by a variety of factors, including the anchoring of these massive vessels.

Firstly, the sheer size and weight of cruise ship anchors can instantly obliterate centuries of coral growth. When anchors are dropped in or near reef areas, they drag across the seabed, crushing coral structures and irreversibly disrupting the delicate marine ecosystem. The impact of anchor damage on coral reefs is significant and far-reaching. Recovery from anchor damage may take up to 50 years, if recovery is even possible.

In addition to anchor damage, cruise ships also contribute to coral reef destruction through other means. The construction of cruise ship ports often involves dredging and blasting, which can directly destroy coral reefs and disrupt marine life. Sediment runoff from construction can smother coral, further degrading the health of these ecosystems. Furthermore, cruise ships generate substantial amounts of waste, including sewage, food waste, and oily bilge water, which they often discharge directly into the ocean. This waste can create acid in the waters and decrease oxygen levels, and increase toxic algae blooms, all of which pose a severe threat to coral reefs.

The impact of cruise ships on coral reefs highlights the need for stricter regulations and sustainable practices in the cruise industry. Governments and cruise lines must work together to implement and enforce measures that protect these fragile ecosystems, such as regulating waste disposal, adopting alternative fuels, and establishing marine protected areas.

Cruise ships emit toxic chemicals from batteries, dry cleaning, and industrial products

Cruise ships are a major source of ocean pollution, and their environmental impact is far-reaching. One of the ways in which cruise ships pollute the ocean is by emitting toxic chemicals from batteries, dry cleaning, and industrial products.

Onboard activities such as photo processing, equipment cleaning, and dry cleaning generate hazardous wastes that include batteries, fluorescent lights, medical waste, and expired chemicals. These materials contain a range of toxic substances, including heavy metals, solvents, and hydrocarbons, which can find their way into greywater, bilge water, or the solid waste stream.

Dry cleaning, in particular, produces perchloroethylene, a toxic chemical that can be harmful to marine life. Batteries also contain various toxic chemicals, such as mercury and other heavy metals, which can leak and mix with oceanic water, causing pollution.

In addition to the wastes generated from these activities, cruise ships also emit air pollutants that contribute to water pollution. The burning of heavy fuel oil, a dirty fossil fuel with high sulfur content, releases dangerous levels of sulfur and heavy metals into the atmosphere. This air pollution can alter the chemical balance of the ocean and contribute to acid rain, which has respiratory and cardiovascular health effects on humans.

The toxic chemicals emitted by cruise ships pose a significant threat to marine life and ecosystems. With the cruise industry's rapid expansion, the environmental impact of these ships is an increasingly pressing issue that requires urgent legislative and regulatory attention.

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