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Executive Summary

Marine ports in the United States are major hubs of economic activity and major sources of pollution. Enormous ships with engines running on the dirtiest fuel available, thousands of diesel truck visits per day, mile-long diesel locomotives hauling cargo and other polluting equipment, and activities at marine ports cause an array of environmental impacts that can seriously affect local communities and the environment. These impacts range from increased risk of illness, such as respiratory disease or cancer, to increases in regional smog, degradation of water quality, and the blight of local communities and public lands.

Most major ports in the United States are undergoing expansions to accommodate even greater cargo volumes. The growth of international trade has resulted in corresponding rapid growth in the amount of goods being shipped by sea. Despite the enormous growth within the marine shipping sector, most pollution prevention efforts at the local, state, and federal level have focused on other pollution sources, while the environmental impacts of ports have grown.

Marine ports are now among the most poorly regulated sources of pollution in the United States. The result is that most U.S. ports are heavy polluters, releasing largely unchecked quantities of health-endangering air and water pollution, causing noise and light pollution that disrupts nearby communities, and harming marine habitats.

In March 2004, NRDC and CCA issued report cards for the 10 largest U.S. ports on their efforts to control pollution -- or lack of efforts to control pollution. In the short time since the grades were issued, steps to reduce port pollution have already been made. For example, the first container ship in the world plugged into shoreside power at the Port of Los Angeles. This report discusses solutions to port pollution problems and provides additional information on the health and environmental impacts of port operations; an overview of policies governing U.S. marine ports; and detailed analysis and technical recommendations to port operators, regulatory agencies, and community-based environmental and health advocates.

Air Pollution and Health Impacts from Port Operations

The diesel engines at ports, which power ships, trucks, trains, and cargo-handling equipment, create vast amounts of air pollution that affect the health of workers and people living in nearby communities and contribute significantly to regional air pollution. More than 30 human epidemiological studies have found that diesel exhaust increases cancer risks, and a 2000 California study found that diesel exhaust is responsible for 70 percent of the cancer risk from air pollution.1 More recent studies have linked diesel exhaust with asthma.2 Major air pollutants from diesel engines at ports that can affect human health include particulate matter (PM), volatile organic compounds (VOCs), nitrogen oxides (NOx), and sulfur oxides (SOx).

The health effects of pollution from ports may include asthma, other respiratory diseases, cardiovascular disease, lung cancer, and premature death. In children, these pollutants have been linked with asthma and bronchitis, and high levels of the pollutants have been associated with increases in school absenteeism and emergency room visits. In fact, numerous studies have shown that children living near busy diesel trucking routes are more likely to suffer from decreased lung function, wheezing, bronchitis, and allergies.3,4,5

Many major ports operate virtually next door to residential neighborhoods, schools, and playgrounds. Due to close proximity to ports, nearby communities face extraordinarily high health risks from associated air pollution. Many of these areas are low income communities of color, a fact that raises environmental justice concerns.

Although cars, power plants, and refineries are all large and well-known sources of pollution, Figure E-1 demonstrates that the air pollution from ports rivals or exceeds these sources. In the Los Angeles area, oceangoing ships, harbor tugs, and commercial boats such as passenger ferries emit many times more smog-forming pollutants than all power plants in the Southern California region combined.6 And the latest growth forecasts predicting trade to approximately triple by 2025 in the Los Angeles region mean that smog-forming emissions and diesel particulate pollution could severely increase in an area already burdened by the worst air quality in the nation. The larger contribution of port sources to air pollution can be attributed to the fact that pollution from cars, power plants, and refineries is somewhat controlled, whereas port pollution has continued to grow with almost no regulatory control.

Figure E-1 uses the Port of Los Angeles and the Port of New York and New Jersey as examples because they are the largest ports on the West Coast and East Coast, respectively. The Port of Virginia is comparable in size to other large ports such as Savannah, Houston, and Seattle. Figure E-1 also highlights emissions of NOx and PM, because these pollutants are associated with very severe health impacts.7 Despite very conservative assumptions used to calculate port emissions, ports outpollute some of the largest sources of harmful emissions, raising the question, Should ports be regulated like other large sources of pollution?

Pollution from Ports Compared to Refineries, Power Plants, and Cars

Water Pollution from Port Operations

Port operations can cause significant damage to water quality-and subsequently to marine life and ecosystems, as well as human health. These effects may include bacterial and viral contamination of commercial fish and shellfish, depletion of oxygen in water, and bioaccumulation of certain toxins in fish.8 Major water quality concerns at ports include wastewater and leaking of toxic substances from ships, stormwater runoff, and dredging.

Land Use Problems at Ports

The highly industrialized operations at ports are often in close proximity to residential areas, creating nuisances and hazards for nearby communities. Ports have several available options to avoid developing new terminals near residential areas. They can develop property previously used in an industrial capacity, or they can increase efficiency of land use at existing terminals. The land use patterns at U.S. ports suggest much room for efficiency improvements. Of the 10 largest U.S. ports, even those that are most efficient in terms of land use-Long Beach and Houston-are four times less efficient than the Port of Singapore, a model of land use efficiency.

Port Community Relations

Ports can be bad neighbors. In addition to the air and water pollution they create, they can cause traffic jams and can be loud, ugly, and brightly lit at night. These impacts range from simple annoyances to serious negative health effects. For example, noise pollution has been linked to hearing impairment, hypertension (high blood pressure), sleep deprivation, reduced performance, and even aggressive behavior.9 At ports bordering residential neighborhoods, bright lights at night and the flashing lights of straddle carriers and forklifts can affect nearby residents, disrupting biological rhythms and causing stress and irritation.10,11 Ports can also be bad neighbors by ignoring residents of the communities living next door, or making little or no effort to solicit community input into operational decisions that will directly affect the life of the community and its residents. Many U.S. ports have developed decidedly hostile relations with their neighbors, not only because of the pollution the ports produce but also because they have consistently ignored residents of nearby communities, refusing sometimes even to share critical information about possible effects of port operations.


The fact-finding for this report revealed untenable situations in many communities near ports: freeways and neighborhood streets overloaded with trucks, homes coated with soot, soaring asthma rates, containers stacked high enough to create significant neighborhood blight, piles of dredged sludge forming toxic islands, and prime marine animal habitats gouged by channeling. The following are recommendations to port operators and policymakers on how to clean up port operations. The recommendations, and the problems they seek to address, are described in greater detail throughout the report.

Recommendations for Ports

Ports must commit to protect local communities and the environment, not only during expansions but also during regular operations. Following are suggested measures used by select ports worldwide to successfully decrease impacts on local communities and ecosystems. These measures should be employed at all container ports to clean up their operations, and local activists should be aware of these options to advocate for their implementation. Ports should consider the negotiation of new or modified leases as an important opportunity to require a combination of the mitigation measures, such as the use of cleaner fuels and equipment.

Marine vessels

  • Clean up harbor craft, such as tugboats, through engine repower and retrofit programs.
  • Limit idling of oceangoing vessels and tugboats by providing electric power at docks and requiring ships and tugboats to "plug in" to shoreside power while at berth.
  • Require ships, including oceangoing vessels, to use the cleanest grade of diesel fuel possible, with a sulfur content of 15 to 2,000 parts per million.
  • Where possible, create incentives for, or otherwise promote the use of, emission controls on oceangoing vessels.

Cargo-handling equipment

  • Retire equipment that is ten or more years old and replace it with the cleanest available equipment and fuel choices, preferably alternative fuels.
  • Retrofit existing equipment less than ten years old to run on the best available control technology, including diesel particulate filters (DPFs) with lean NOx catalysts (LNCs) and, if not feasible, with diesel oxidation catalysts (DOCs).
  • Switch to cleaner diesel fuels, such as low-sulfur fuel with sulfur content less than 15 parts per million and diesel emulsions.

On-road trucks

  • Create incentive programs that encourage fleet modernization, the retirement of older trucks, and their replacement with modern lower-emitting trucks.
  • Offer incentives for the installation of pollution controls, including DPFs with LNCs or, if not feasible, with DOCs.
  • Make cleaner fuels, such as diesel emulsions or low-sulfur diesel, available to off-site trucks.
  • Minimize truck idling by enforcing idling limits or by installing idle shutoff controls.


  • Repower or replace all switching locomotives that do not meet the Environmental Protection Agency (EPA) Tier 0 Standards with electric-hybrid or alternative-fuel engines.
  • Install engine emissions controls where possible.
  • Require automatic engine shutoff controls to minimize unnecessary idling.
  • Commit to using cleaner fuels, such as on-road grade diesel.

Stormwater management

  • Take principal responsibility, as the general permittee, for preparing a stormwater pollution prevention plan for all terminals.
  • Provide guidance to all port tenants for development of model stormwater programs, oversight and inspections of individual terminals to confirm implementation of an acceptable program, and education and training of terminal staff.
  • Carefully document and analyze potential water pollution problems, water quality monitoring, and best management practices for the prevention, control, and treatment of stormwater runoff. Other measures recommended include water quality programs; traffic mitigation; land use, light, and noise abatement; improved aesthetics; and other terminal design features.

Recommendations for Policymakers

In addition to the mitigation measures ports should implement on their own, a number of policy and regulatory actions are needed to protect human health and the environment from the large, industrial, and high-polluting operations at marine ports. Ordinarily, such activities would be subject to stringent regulation, but oversight of ports falls between the regulatory cracks, defeated by confusion over jurisdictional authority and the ongoing efforts of a strong industry lobby. While a patchwork of international, federal, state, and local rules apply to various pollution sources at ports, most are weak and poorly enforced.

Marine vessels

  • The U.S. government should officially ratify MARPOL Annexes IV and VI (an international treaty that prevents sewage pollution and sets emissions standards for ships) and the Antifouling Systems Convention, which bans toxic chemical coatings on ship hulls.
  • The EPA should expedite efforts to establish the entire East, West, and Gulf coasts as control zones subject to stricter emission standards under MARPOL VI.
  • The EPA should implement a graduated harbor fee system similar to a program in Sweden that requires more polluting ships to pay higher fees upon entering a port.
  • The EPA should expedite implementation of stricter emission standards for all marine vessels within two years.
  • States and regional authorities should create financial incentives for the cleanup and replacement of older marine vessels.
  • States and regional authorities should require ships to plug in to shoreside power while docked.
  • States should require that ships use low-sulfur diesel while in coastal waters and at berth (until electric power is made available). In the absence of state action, regional authorities should require this.
  • Regional authorities should monitor and enforce ship speed limits.

On-road and nonroad vehicles

  • The EPA must follow through with full implementation of its 2007 emissions standards for on-road, heavy-duty trucks; its 2008 emissions standards for nonroad vehicles and equipment; and the related lower sulfur diesel requirements.
  • The EPA should adopt a series of diesel retrofit rules, similar to those proposed in the California risk reduction program, to establish a cleanup schedule for existing polluting diesel engines. In the absence of federal action, states or local authorities should adopt these programs.
  • The EPA should set uniform federal idling limits for all diesel engines. In the absence of federal action, states or local authorities should require idling limits.
  • States should provide incentive programs to reduce pollution from heavy-duty diesel engines, similar to programs such as California's Carl Moyer and Gateway Cities; in the absence of state action, regional authorities should sponsor such programs.
  • Regional authorities should adopt fleet rules to clean up and require new, cleaner purchases of all heavy-duty engines, similar to those in place in the Los Angeles area.

Inland cargo transport

  • The EPA and individual states should consider fees on each container entering a port to provide funding for mitigation of the environmental impacts of moving those containers.
  • The U.S. government should adopt and support a sustainable transportation system program, similar to the European Union program, facilitating the shift of cargo transport from more polluting modes (such as trucking) to cleaner locomotive and barge transport.


  • The EPA should implement stricter emission standards for locomotives within one year.
  • States and regional authorities should also create financial incentives for the cleanup and replacement of older locomotives.
  • States should negotiate memorandums of understanding that create incentives for cleaner locomotives. In the absence of state action, regional authorities should pursue this.

Land use

  • Regional authorities should improve efforts to protect marine habitats from further infill due to port developments.
  • Regional authorities should work together with local communities and marine terminals to improve efficiency and land use and to minimize impacts of terminals on local communities.

Community relations

  • Neighboring states should work together in coastal alliances to protect their marine natural resources and to share information on programs and technologies, and they should work together to jointly shoulder the neglected responsibility to neighboring communities and their surrounding environment.


  • The EPA should issue effluent guidelines to require a general baseline level of pollutant reduction for port facilities, or for those pollutants typically found in port runoff.
  • States should ensure that anti-degradation provisions of federal and state law are fully implemented in stormwater permits.
  • States should give special attention to the development of total maximum daily loads (TMDLs) for impaired waters around many ports.
  • Local governments should prioritize port facilities when designing inspection protocols in conjunction with local regulatory programs and implementation of municipal stormwater permits.

Oil spills

  • Congress should pass the Stop Oil Spills Act (H.R. 880) to accelerate the phase-in of double-hulled tankers in U.S. waters by 2007.
  • Regional authorities should require ports to take steps to ensure that oil pollution does not become part of runoff and that portwide oil-recycling programs are in place.

Ballast water

  • The U.S. Coast Guard should finalize mandatory national ballast water regulations as quickly as possible, or no later than the expected summer 2004 completion date.
  • States should adopt ballast water regulations, similar to those in place in California and Washington, that ensure a 200-mile buffer from the U.S. coast.

Waste discharge

  • The EPA must consider more stringent requirements on the dumping of wastes containing oxygen-depleting nitrogen and phosphorous, as well as persistent toxic compounds that continue to threaten marine life.


Based on our previous survey of 10 of the largest container ports in the United States, not nearly enough is being done to alleviate the severe impacts of the highly polluting shipping industry despite real and significant environmental and health impacts associated with marine port operations. Ports should take internal measures to reduce pollution caused by port activities. Likewise, regulatory agencies at the federal, state, and local level must provide long overdue safeguards. Further, if port expansions are to continue, all projects must be mitigated to the maximum extent possible, efficiency must be improved, and current operations should be cleaned up.


1. California Air Resources Board, Diesel Risk Reduction Plan, October 2000.

2. RJ Pandya, GM Solomon, A Kinner, JR Balmes, "Diesel exhaust and asthma: Hypotheses and molecular mechanisms of action," Environmental Health Perspectives, Vol. 110, Supplement 1 (2002):103-112.

3. B Brunekreef, NA Janssen, J de Hartog, H Haressema, M Knape, P van Vliet, "Air pollution from truck traffic and lung function in children living near motorways," Epidemiology, Vol. 8 (1997): 298-303.

4. G Ciccone, F Fostastiere, N Agabati, A Biggeri, L Bisanti, E Chellini, "Road traffic and adverse respiratory effects in children," Occupational and Environmental Medicine, Vol. 55 (1998): 771-778.

5. H Duhme, SK Weiland, U Keil, B Kraemer, M Schmid, M Stender, L Chambless, "The association between self-reported symptoms of asthma and allergic rhinitis and self-reported traffic density on street of residence in adolescents," Epidemiology, Vol. 7 (1996): 578-582.

6. Diane Mitchell, "Health Effects of Shipping Related Air Pollutants," California Air Resources Board, Presentation to EPA Region 9 Conference on Marine Vessels and Air Quality, Feb. 1, 2001.

7. NOx and PM emissions for refineries, power plants and cars were taken from total U.S. emissions in EPA's National Emission Trends, 2000. The national emission totals were then divided by the total number of refineries, power plants and registered passenger vehicles in 2000. Emissions per avg. U.S. passenger car were then multiplied by 500,000 to represent that amount of cars. NOx and PM emissions for the ports of Virginia, New York and New Jersey, and Los Angeles were based on the same calculations.

8. The Ocean Conservancy, Cruise Control: A Report on How Cruise Ships Affect the Marine Environment, May 2002.

9. World Health Organization, "Guidelines for Community Noise," 1999. www.who.int/docstore/peh/noise/Comnoise-1.pdf (11 May 2004).

10. Ibid.

11. Health Council of the Netherlands, "Impact of outdoor lighting on man and nature," The Hague: Health Council of the Netherlands, Publication No. 2000/25E, 2000, http://www.gr.nl/pdf.php?ID=321 (11 May 2004).

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last revised 3/18/2004

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