An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Ports Primer: 7.1 Environmental Impacts

1.0 Ports Primer Home   2.0 The Role of Ports   3.0 How Ports Work   4.0 Port-Community Relations   5.0 Land Use and Transportation   6.0 Local and Regional Economy   7.0 Environmental Impacts   8.0 Tools and Resources   9.0 Appendix   Glossary   Endnotes
On this page:

Port operations can lead to environmental impacts on air, water and land. Many communities with environmental justice concerns also experience disparities in health outcomes that they attribute to exposure to emissions from port operations. Ports are required to mitigate port projects and operations.

The Environmental Protection Agency has authority to address some but not all causes of these impacts. For example, EPA has regulated manufacturers to build cleaner engines, but EPA can’t mandate use of clean equipment or control hours of operation of port equipment. EPA also has no authority to regulate land use. EPA can assess the environmental impacts of siting a new highway but has limited authority to prevent that highway from being built.

Climate Adaptation

Ports rely on a wide range of vehicles with dieselHelpdieselA type of fuel typically used in a compression-ignition engine. In common maritime use, diesel can refer to several varieties of fuels including Marine Diesel Oil (MDO) and Marine Gas Oil (MGO). Diesel may also be labeled by its sulfur content, such as the case of LSD (low sulfur diesel with less than 500 parts per million (ppm) sulfur) or ULSD (ultra-low sulfur diesel with less than 15 ppm sulfur). engines, which are a source of greenhouse gas (GHG) emissions and affect climate change. This is discussed further on the Air Emissions page.

In addition, due to their coastal locations, seaports are increasingly devoting substantial resources to address risks associated with extreme weather events. Flooding associated with extreme weather events stands out as one of the most significant risks to ports. Flooding has the potential to damage electrical substations, as well as electrical motors on wharf cranes and ground level electric pumps. It can also destroy cargoHelpcargoThe freight (goods, products) carried by a ship, barge, train, truck or plane.. Ports are developing plans to mitigate the effects of climate change-related extreme weather events.

For more information: Ports Planning for Climate Change Impacts (PDF) (17 pp, 351 K, About PDF) 

Top of Page


Air pollution is a significant concern at port facilities. Mobile sources at ports release pollutants including particulate matterHelpparticulate matterRefers to small particles in the air that can be measured to determine air quality and potential health impacts. Airborne PM can result from direct emissions of particles (primary PM) or from the condensation of certain gases that have themselves been directly emitted or chemically transformed in the atmosphere (secondary PM). PM is often classified by size: PM2.5 and PM10. (PM), nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), and air toxics.

Sources of air pollution at ports can include:

                                                                                            Examples of Sources of Air Pollution at Ports
Transportation Sources Stationary Sources
Trucks Refineries
Marine vessels Oil and gas storage facilities
Trains Power generation
Cargo handling equipment Storage of open piles of coal

" "Air pollution can affect our health in many ways. Numerous scientific studies have linked air pollution to a variety of health problems including: (1) aggravation of respiratory and cardiovascular disease; (2) decreased lung function; (3) increased frequency and severity of respiratory symptoms such as difficulty breathing and coughing; (4) increased susceptibility to respiratory infections; (5) effects on the nervous system, including the brain, such as IQ loss and impacts on learning, memory, and behavior; (6) cancer; and (7) premature death. Some sensitive individuals appear to be at greater risk for air pollution-related health effects, for example, those with pre-existing heart and lung diseases (e.g., heart failure/ischemic heart disease, asthma, emphysema, and chronic bronchitis), diabetics, older adults, and children.

Air pollution also damages our environment. For example, ozone can damage vegetation, adversely impacting the growth of plants and trees. These impacts can reduce the ability of plants to uptake carbon dioxide (CO2) from the atmosphere and indirectly affect entire ecosystems.

Top of Page


" "Port operations can have a significant impact on water quality and the health of marine life. Waste from ships and other port activities can result in loss or degradation of habitat areas and can also harm marine life. Known impacts of port operations include:

  • Wastewater: Ships periodically release sewage, wastewater and bilge water, which is wastewater that is often contaminated with oil. Discharges are regulated by federal state and local governments, including port authorities.
  • Ship paint: Leaching of toxic paint additives, meant to prevent barnacles from clinging to ships, can result in health impacts on marine life.
  • Stormwater runoff: Stormwater runoff gathers pollutants from paved surfaces at the port and deposits them in the water, often bypassing wastewater treatment plants.
  • Nitrogen: Nitrogen is the leading cause of eutrophication in marine systems, where algae blooms use up oxygen in the water and cause fish and shellfish to die.
  • Oil spills: Oil contamination can include chronic pollution from runoff, bilge water, and the loading and unloading of oil tankers, as well as larger spills resulting from overfilling tanker ships or tears in a ship’s hull.
  • DredgingHelpdredgeThe process of removing sediment from harbor or river bottoms for safety purposes and to allow for deeper vessels.: Removing sediment to deepen ship channels can increase the cloudiness of water and disturb contaminated bottom sediment, harm or permanently destroy critical wildlife habitats, and disturb or kill threatened and endangered species.
  • Invasive species: Marine animals can be taken into ships through ballast waterHelpballast waterFresh or salt water, sometimes containing sediments, held in tanks and cargo holds of ships to increase stability and maneuverability during transit. that is used to help maintain ship balance and then transported across the world to new habitats where they may become invasive species that threaten the balance of natural ecosystems.

Top of Page

Risks and Health Impacts2

" "Disparities in health outcomes are often a primary environmental justice concern for near port communities. Characterizing these disparities in health outcomes, evaluating their implications, and managing them is a challenge for communities.

EPA has tools that can help communities characterize these risks. These tools can help communities address:

  • How to conduct a health risk assessment for exposure to an individual pollutant
  • How to conduct a health risk assessment for exposure to a chemical mixture
  • How to evaluate risks from multiple chemical stressors
  • How to evaluate risks from exposures in children, and impacts of early life exposures
  • How to evaluate cancer and non-cancer risks

Top of Page

Select to go forward or back.