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Resource Issue: Cruise Ships

cruise shipLarge cruise ships began visiting Monterey in 2002. These ships can provide local businesses with economic benefits, particularly if they introduce the region to tourists who may return for later visits. However, both the public and businesses have raised concerns about environmental issues associated with these ships.

Due to cruise ship visitation to Monterey Bay, and concern over potential impacts to marine resources from these vessels, this issue has drawn significant attention from the public. At the February 7, 2003 meeting, the MBNMS Advisory Council passed a resolution recommending that MBNMS staff pursue a regulatory prohibition on harmful discharges from cruise ships.

As a result of the MBNMS Management Plan Initiative the MBNMS regulations were amended to prohibit the discharging or depositing from within or into the MBNMS any material or other matter from a cruise ship except clean vessel engine cooling water, vessel generator cooling water or anchor wash. The Cruise Ship Action Plan was also developed and outlines specific strategies and actions for addressing the threats posed by harmful cruise ship discharges. It includes outreach to the cruise industry regarding Sanctuary policies, developing enforcement and monitoring programs and creating a cruise ship passenger education program.

Under the Clean Water Act and MBNMS regulations, the following prohibitions apply within the sanctuary:

  • MBNMS regulations prohibit the discharge of raw sewage and require that discharges from vessels throughout the Sanctuary occur through a properly functioning Type I or Type II MSD that meets the standards of Section 312 of the Clean Water Act.
  • MBNMS regulations generally prohibit discharges to the Sanctuary, but provide an exception for discharges from routine vessel operations as mentioned above.
  • MBNMS regulations prohibit the discharge of oily wastes from bilge pumping at any concentration.


Environmental Impacts of Cruise Ships and Current Regulation

Sanctuary's Sharkcat monitors cruise shipDue to their sheer size and capacity for passengers, cruise ships can cause serious impacts to the marine environment. The main pollutants generated by a cruise ship are: sewage (also referred to as black water); gray water; oily bilge water; hazardous wastes; and solid wastes.


Sewage includes vessel sewage and wastewater from medical facilities. Sewage from ships is generally more concentrated than that from land based sources, as it is diluted with less water when flushed (three quarts versus three to five gallons). Sewage discharge can contain bacteria or viruses that cause disease in humans and other wildlife. It can present a public health concern, if discharged in the vicinity of marine life harvested for human consumption, or in or near waters used for recreational activities such as swimming, diving, or boating. Nutrients in the sewage can cause eutrophication, whereby excessive growth of algae depletes oxygen and can lead to the death of fish and other organisms. Additionally, chemicals and deodorants including chlorine, ammonia, or formaldehyde are often used in Marine Sanitation Devices (MSD) ( and can present a threat to marine organisms. Volumes of sewage for a typical cruise ship have been estimated at 8.4 gallons per person per day, or 147,000 gallons per week.

Celebrity Cruise ShipGraywater

Graywater consists of wastewater from sinks, showers, laundry, and galleys. It can contain a number of pollutants including: suspended solids, oil, grease, ammonia, nitrogen, phosphates, copper, lead, mercury, nickel, silver and zinc, detergents, cleaners, oil and grease, metals, pesticides, and medical and dental wastes. A typical cruise ship produces an estimated 1,190,000 gallons of graywater per week.

Bilge Water

Bilge water consists of fuel, oil, and wastewater from engines and machinery that collects, along with fresh water and seawater in the area at the bottom of the ship's hull, as a result of spills, leaks, and routine operations. It may also contain other materials such as rags, cleaning agents, paint, and metal shavings. A typical cruise ship generates an estimated 18,500 gallons of bilge water per week.

Ballast Water

Cruise ships take in millions of gallons of ballast water, in order to stabilize the vessel for safe and efficient operation. During the process they take in thousands of species of marine organisms, including various types of larvae, fish eggs, and microorganisms. The water is often drawn in from coastal waters in one area, and discharged at another location. This process has led to the introduction of invasive species, which disrupt marine ecosystems, and cost the U.S. billions of dollars per year.

Ballast water operations are currently regulated by Marine Invasive Species Program administered by the State Lands Commission. The California Marine Invastives Species Program ( requirements vary depending on whether the vessel arrives from inside or outside of the Pacific Coast Region, and whether ballast water is from inside or outside of the Pacific Coast Region.

Hazardous Materials

Hazardous wastes produced on cruise ships include by-products of dry cleaning and photo processing operations, paints and solvents, batteries, fluorescent light bulbs containing mercury, and wastes from print shops. A typical ship produces an estimated 110 gallons of photo processing chemicals, five gallons of dry cleaning wastes, and ten gallons of used paints per week. These substances can be toxic or carcinogenic to marine life.

Solid Wastes

Plastic debris can be ingested or cause entanglement to marine life including marine mammals, seabirds, and sea turtles. Solid wastes generated by cruise ships include large volumes of food waste, cans, glass, wood, cardboard, paper, and plastic. In some cases the wastes are incinerated on the vessel and the ash is discharged at sea; other wastes are disposed of on shore or recycled. The Marine Plastic Pollution and Control Act regulate the disposal of plastics and garbage pursuant to ANNEX V of MARPOL. Under these regulations the disposal of plastics is prohibited in any waters, and floating dunnage and packing materials are prohibited in navigable water within twenty-five nautical miles from land. Other garbage including paper, glass, rags, metal, and similar materials is prohibited within twelve nautical miles from shore (unless macerated, in which case it can be disposed of on land).

ResidenSea cruise ship in Monterey Harbor

Cruise Line Industry Violations

The cruise line industry historically has had a relatively poor record regarding environmental violations. The vast majority of cruise ships are foreign flagged. According to a report published by the Government Accounting Office, there were eighty-seven confirmed illegal discharge cases from cruise ships between 1992 and 1998 in U.S. waters. Eighty-one of these cases involved oil, and six involved plastic or garbage. Seventy-five percent of these violations were accidental (human or mechanical error).

Cruise Line Industry Initiatives

A number of cruise lines have made significant improvements to address environmental concerns in recent years. The Cruise Lines International Association (CLIA) ( is the main trade association that represents 16 of the world's largest cruise lines (95% N American Market, 85% worldwide), and serves as a consultative organization to the International Maritime Organization (IMO) ( CLIA lines reported a reduction in waste by more than 50% between 1992 and 2002. In 2001, the Cruise Industry Waste Management Practices and Procedures document was adopted by CLIA members, and is now a mandatory condition for membership in the organization. Several cruise lines have adopted even more stringent voluntary measures, including Celebrity cruises, whose vessels are required by corporate policy to discharge black water no closer than 12 miles from shore.





URL:    Reviewed: November 20, 2017
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