Environmental Social Governance (ESG) Reporting for Large US Airports

Abstract

This paper provides a novel approach to airport sustainability with a comparative analysis of frameworks presented by Airports Council International (ACI) and the World Economic Forum (WEF), a case study on environmental social governance (ESG) reporting for large US airports, a historical perspective and discussion regarding legal considerations, and sustainability metrics. Airport sustainability reporting provides numerous advantages, including enhanced transparency and accountability, and it also supports risk management, regulatory compliance, operational efficiency, risk management, community engagement, and investor relations. There are 30 large hub airports in the US, and each one of these publishes information on sustainability, which may consist of a sustainability report, reports on sustainability related topics, or website information. Eight of these large US airports publish an ESG report. ESG reports are of increasing interest due to their use internationally and due to the role of ESG reports in investment decisions. This paper presents an analysis of the information contained in ESG reports published by US airports and compares the frame of reference used by airports that utilize UN Sustainable Development Goals (SDGs) in their reporting. Case studies of ESG reports for Salt Lake City and Dallas Fort Worth Airports are presented to illustrate ESG reports, and the use of the SDG identified in these reports is compared the framework identified by Airports Council International (ACI) and the World Economic Forum (WEF). The discussion of airport ESG reporting provides a thorough and contextual review of the topic and examines how this framework may evolve to address the increasing interest in ESG reporting for US airports. The information provided may be used by airports to improve their sustainability reporting.

1. Introduction: The Evolution of Sustainability at Airports

Sustainability is a historic concept, and even ancient cultures limited the use of natural resources to ensure preservation of natural resources and a way of life [1]. The evolution of sustainability at airports in the United States (US) began more than fifty years ago with environmental awareness and national supporting legislation and evolved in the next couple decades with individual programs, such as noise mitigation programs and programs that support social objectives. By the turn of the century, the foundation was laid for more formalized sustainability programs, and the Federal Aviation Administration (FAA) and some airports began to initiate broader sustainability efforts. While some airports have developed sustainability plans and a few publish Environmental Social Governance (ESG) reports, sustainability reporting is still relatively immature at US airports.

The modern era of environmental awareness in the US gained momentum in the 1960s and 1970s, which was reflected in 1970 by the creation of the US Environmental Protection Agency (EPA) to ensure protection of the environment as well as human health [2]. As a result of this legislation, US airports were required to assess the environmental impact of their actions, including the construction of new runways and other airport development projects. At about the same time, the Airport and Airway Development Act of 1970 provided federal funds to airports for the creation of airport master plans. Airport master plans address financial and operational considerations and also require public involvement, which reflects the integration of a social component into airport planning. The impact of this legislation increased with the Airport and Airway Development Act Amendments of 1976, which included provisions for federal funding for airport noise mitigation, including airport land purchases to support environmental compatibility. Deregulation via the Air Cargo Deregulation Act of 1976 and the Airline Deregulation Act of 1978 spurred a dramatic increase in air travel and had a significant impact on US airports. Funds to support the development needs of airports continued to be provided through federal programs. Support for environmental impacts also expanded, and activities to further support noise mitigation and compatibility planning for adjacent land uses were addressed by the Aviation Safety and Noise Abatement Act of 1979. A decade later, the Airport and Airway Safety and Capacity Act of 1987 included a requirement that ten percent of the federal funds for airport development support Disadvantaged Business Enterprises (DBE), which are typically smaller firms owned by people who are socially and economically disadvantaged. The Airport and Airway Safety, Capacity, Noise Improvement and Intermodal Transportation Act of 1992 further supported social objectives through requirements that airports comply with the American with Disabilities Act of 1990 and supported environmental objectives through requirements that airports comply with the Clean Air Act and the Federal Water Pollution Control Act.

Airports were increasingly considering the environmental and social impacts of their activities; however, in many cases, their activities were addressed by separate programs, and actions may not have been integrated into a comprehensive sustainability program. This reflects a larger context for sustainability, and the goals to protect the environment as well as human health, combined with the need to have economic success, are reflected in the Triple Bottom Line (TBL) framework, which was introduced in 1994 by Elkington to examine corporate impact [3] and provide a catalyst for broader change [4]. Since then, new sustainability rating systems have been developed, and additional considerations have broadened the concept of sustainability. Sustainability in the aviation industry, including airlines and airports, has increased in recent years. In response to increasing interest and the increasing use of ESG reporting, some airports have begun publishing ESG reports. This reflects requirements in Europe for ESG reporting and investor interest. Airport sustainability reporting provides numerous advantages, including enhanced transparency and accountability, and it also supports risk management, regulatory compliance, operational efficiency, risk management, community engagement, and investor relations. This paper examines the history of sustainability concepts for airports, discusses rating systems and legal considerations, provides a review and analysis of the large hub US airports that currently use ESG reporting, and presents two case studies for large hub airport ESG reports.

This paper presents a literature review of topics related to airport sustainability and analysis of ESG reporting for large hub airports based on publicly available information. Following this section, this paper provides a narrative literature review of the history of sustainability for US airports and the global context for aviation sustainability provided by the International Civil Aviation Authority (ICAO) and the United Nations (UN), discusses commonly used sustainability rating systems and reporting frameworks, and identifies related legal considerations. Details of sustainability reporting frameworks suggested by the World Economic Forum (WEF) and Airports Council International (ACI) are provided, since these may be appropriate for airport use. This literature review provides an important context for airport ESG reporting.

The second component of this paper is an analysis of ESG reports for US airports. This includes the identification of sustainability reporting practices for large hub US airports, and more detailed analysis of the information for those that have published ESG reports. Analysis includes a comparison, content analysis, and case studies of ESG reports for Salt Lake City Airport (SLC) and Dallas–Fort Worth Airport (DFW), both of which reference the UN Sustainable Development Goals (SDGs). The final analysis component is a comparison and discussion of the SLC and DFW SDGs with the framework outlined by the WEF and ACI.

2. Literature Review

Sixteen years after Elkington introduced the TBL, the FAA started the Airport Sustainable Master Plan Pilot Program in 2010. They provided federal funds for sustainability planning through either a stand-alone sustainability plan or a sustainability component incorporated as a new chapter within the airport Master Plan (federal funding for Master Plans was initiated in the 1970s). The focus of the Pilot Program was to develop a Sustainable Management Plan that protects the environment, supports economic growth, and supports social progress [5]. The sustainability plan needed to include a baseline assessment as well as measurable goals and supporting initiatives to reduce the environmental impact of the airport [5]. Airport sustainability planning was initially supported by the Sustainable Aviation Guidance Alliance (SAGA), with hundreds of sustainability practices and metrics [6]. Although this information was endorsed by the FAA’s Guidance in 2010, most of the SAGA information has not been updated in almost a decade, and other resources have been developed and are more widely used. There were a number of valuable lessons learned from the FAA Airport Sustainable Master Plan Pilot Program [7], including the benefits of integrating sustainability planning with other planning activities, involving stakeholders in sustainability planning, and providing a framework for assessment, as described below. It is most effective to integrate sustainability considerations into all aspects of master planning, rather than to consider sustainability as a “standalone topic” and address it as a separate chapter. As with all planning activities, ensuring that all stakeholders are included is critical for a successful plan and to ensure future support for the activities outlined in the plan. Stakeholders that should be involved include airport personnel at all levels as well as regulatory organizations and local community representatives. This need for stakeholder involvement is consistent with practices that are well established for airport master planning activities. Another successful strategy is the use of baseline assessments, combined with appropriate metrics and a system to track progress. This supports realistic goals as well as transparency and accountability. While these lessons learned are useful, the FAA also acknowledges that each airport is different, and it is important that the process allow airports to tailor their approach to their own situation. These lessons learned can be integrated into the sustainability planning efforts for airports that are initiating their sustainability plans.

Given that a core function of airports is to safely serve air traffic, the FAA has expanded the traditional TBL approach to encompass Airport Operations, as shown in Figure 1. The inclusion of airport operations reflects the fact that operational safety and efficiency are key considerations for airports. The inclusion of environmental considerations encompasses a broad array of possible topics, including water, air quality and emissions, and noise. The economic component reflects that US airports are considered a “business enterprise” model, in which the airport is a public entity but is expected to cover costs (whenever possible) and be managed as if it were a business. The social component is referred to as community and may include the local community in which the airport resides, the community of airport employees, and the larger aviation community, reflecting connections to other airports and global aviation goals. The Figure 1 framework is also termed EONS, reflecting economic, operational efficiency, natural resources (aka environmental), and social responsibility [8]; EONS is used by both the FAA and ICAO, and it is applicable to airport terminals as well as cargo buildings, ATC towers, hangars, parking structures, office buildings, fuel farms, and fire stations. The integration of operational efficiency into sustainable development may reflect priorities that already existed at many airports. Many airports have programmed projects that support and enhance operational efficiency, these projects include the end-around taxiways at large airports, such as Hartsfield–Jackson Atlanta International Airport (ATL), Detroit Metropolitan Wayne County Airport (DTW), and Dallas–Fort Worth International Airport (DFW); the pedestrian walkway at Seattle–Tacoma International Airport (SEA), which supports efficiency for passenger movement in the terminal and efficient movement of aircraft; and the construction of a midfield terminal at Indianapolis International Airport (IND), which reduced aircraft taxi times and fuel consumption.

The FAA is committed to airport sustainability, which reflects societal concerns about climate change, energy efficiency, natural resources, and clean water, as well as economic considerations and social impacts. The FAA’s sustainability efforts are often focused on sustainable aviation fuel (SAF), technologies for more efficient aircraft, operational efficiency of the National Airspace System (NAS), and reduced noise impacts [10]. While SAF is critical to meet aviation’s goal of net-zero GHG emissions by 2050 [11], challenges include an inadequate supply of SAF, issues due to different SAF standards in different parts of the world (e.g., Europe vs. US), and concerns that SAF made from corn and soy will increase food prices [12].

The FAA’s framework for airport sustainability has a strong focus on airport development, including airport construction projects. This makes sense given the FAA’s role in funding airport development in the US for the 3287 airports in the National Plan of Integrated Airport Systems (NPIAS) [13]. The FAA provides funding for sustainability planning but does not endorse or require sustainability certification or a rating system, although there are a number of sustainability rating systems and certifications that are used by airports.

In 2012, the FAA suggested that airports should develop a sustainability mission and supporting categories that reflect the needs of their airport rather than use standard language or categories from the FAA [7]. Perhaps this flexible and tailored framework is one reason why there are a variety of approaches to airport sustainability.

There were six recent literature reviews related to airport sustainability, and each review provides a very different approach to the context for airport sustainability. The first literature review published in 2020 suggests that there are five sustainability categories for airports [14]:

• Energy and atmosphere (energy management, renewable energy, and energy emissions);
• Comfort and health (indoor and ambient air quality and building occupant comfort),
• Water and wastewater (conservation and water quality);
• Site and habitat (habitat, transportation, and resilience);
• Materials and resources.

A review by Raimundo et al. in 2023 suggests that airport environmental sustainability should be assessed based on environmental and energy management, and the following categories should be considered [15]:

• Greenhouse gas (GHG) emissions for pavements;
• Energy management strategies for aircraft operations and airport buildings;
• Conservation of water;
• Waste management.

A review by Papagrigoriou et al. (2023) examined strategies that airports have taken and suggested that airport environmental issues include the following [16]:

• Clean energy sources, such as solar panels; energy efficiency, such as green building designs (including LEED certification); and efficient lighting and HVAC;
• In addition to HVAC, information and communication technology is a major energy consumer;
• Quantity of energy used and associated emissions of carbon and greenhouse gases (GHGs);
• Noise, which in some cases limits operation (66% of European airports have restrictions on noise);
• Consumption of natural resources, land use impacts, and impacts on biodiversity and microclimates.

A review by Bahman in 2023 examined the life cycle assessment for airport sustainability and suggested that environmental impacts of auxiliary power units and ground support equipment (GSE) during aircraft turns and alternative fuels should be explored to reduce environmental impacts [17].

A review by Jia et al. in 2023 focused on three methods for assessing sustainability in a broad range of industries, including the airport sector [18]. This research, which focused on methodologies reflecting data envelop analysis, hybrid multi-criteria decision making, and composite index-based assessments, found that more holistic modeling of sustainability is needed, as it is a standard for sustainability.

In 2024, Chen et al. published a review that focused on the environmental sustainability of airport operations, with a focus on operations research [19]. This review identified that environmental issues, such as air pollution and noise, may be addressed through airport traffic flow optimization, specifically identifying the following activities for optimization [19]:

• Aircraft gate assignments and aircraft pushback;
• Taxi and tow operations;
• Runway scheduling;
• Aircraft trajectories.

While these reviews lend some insight into topics and categories that are used to assess and discuss airport sustainability, if anything, the results highlight that airport sustainability can be analyzed and interpreted in many ways, and there is no one approach to airport sustainability.

Table 1. Example categories addressed by various sustainability frameworks and rating systems.

	Economic	Environment	Environment Facilities	Social	Other
Elkington Triple Bottom Line (1994) [3]	Economic	Environmental		Social
ICAO EONS (2019) [8]	Economic Operational efficiency	Natural resources		Social
FAA Interim Guidance on Sustainable Master Plan Pilot Program (2010) [5]	Procedures	Environmental resources Air quality Water Quality Noise	Facilities	Socioeconomic
FAA Sustainable Master Plan Pilot Program Lessons Learned (2012) [7]	Waste management and recycling Energy reductions 1	Natural resource management Emissions reduction Water quality and conservation Air quality	Construction methods Land use
ACI ACERT and Airport Carbon Certification (n.d.) [21]	Emissions due to airport vehicles		Emissions Terminal HVAC Offsite due to energy used by airport Airport supply chain (e.g., airline activities, passenger arrivals)
ACI Sustainability Strategy for Airports Worldwide (2021) [22]	Economic impact (direct and indirect) Market presence and connectivity Sustainable Supply chain Anti-corruption	Climate change Energy and emissions Water and effluents Waste management Biodiversity		Communities and noise Service quality Employment Health and safety	Governance 2
LEED for Commercial Projects [23]	Integrated process	Water efficiency Energy and atmosphere Materials and resources	Location and transportation Sustainable sites	Regional priorities	Indoor air quality Innovation
Institute for Sustainable Infrastructure Envision [24]	Resource allocation	Natural world Climate and resilience	Building assessment for optimal design and operations for people	Leadership Quality of life
WELL [20]		Health and well-being Air Water	Building assessment for optimal design and operations for people		Health and well-being Lighting Fitness Comfort Mind Nourishment

¹ Energy reduction is also applicable to facilities and economic elements. ² Governance could be considered as Social or Other.

presents sustainability topics based on Elkington’s TBL approach and illustrates how more recent frameworks have maintained a strong focus on environmental topics (e.g., clean air, clean water, reduced waste) and energy efficiency, while expanding social components beyond employee resources to community health and welfare; the increased focus on health and well-being includes expanded categories for human health under the WELL framework [20].

Sustainability plans funded by the FAA have now been completed for over 40 airports [9], including large airports, such as Atlanta and Dallas–Fort Worth, as well as smaller general aviation airports. In addition to sustainable master plans, the FAA supports sustainability through the Noise Compatibility program (aka Part 150), the VALE grant program (aka Voluntary Airport Low Emissions, with funds to reduce emissions through geothermal and other initiatives), and detailed Environmental Impact Statements (EIS). The FAA develops an EIS anytime there is an airport project with the potential to have a significant impact on the environment. Example topics included in an EIS are shown in the list below [25]:

• Noise;
• Land use;
• Air quality;
• Water quality;
• Historic and cultural resources;
• Biotic communities;
• Wetlands;
• Floodplains;
• Wild and scenic rivers;
• Light emissions;
• Solid waste and hazardous materials;
• Construction impacts.

2.1. Sustainability Rating Systems

Two widely used sustainability rating systems are Envision, which is used for infrastructure, and LEED, which is used for buildings (and less often airport campuses). Envision has been used at a number of airports [26]:

• Hartsfield–Jackson Atlanta International Airport (ATL) pavement replacement for taxiway and runway 9 L;
• Nashville International Airport (BNA) water source geothermal system;
• Portland International Airport (PDX) rental car quick turnaround facility;
• San Diego International Airport (SAN) Terminal 2 parking plaza;
• Phoenix Sky Harbor International Airport (PHX) Sky Train.

Envision encompasses five categories (quality of life, leadership, resource allocation, natural world, and climate and resilience); these five categories address human well-being, mobility, community development, collaboration, planning, economy, materials, energy, water, siting, conservation, ecology, emissions, and resilience [24].

The LEED rating system can be used for terminals, airport office space, aircraft hangars, and rental car centers [27]. LEED was initially developed for buildings but has expanded to include campuses (e.g., Indianapolis International Airport campus). The LEED rating system reflects design, construction, operations, and maintenance.

New rating systems are still being developed. Recently, some airports have used WELL certification, which focuses on optimal design and operations for people and focuses on factors that impact health and well-being, such as air, water, nourishment, light, fitness, comfort, and mind [20]. WELL can be used for new and existing airport buildings and interiors. Terminal 1 at San Francisco International Airport included both LEED Platinum and WELL certifications. Although not used in the US, Delhi International Airport recently received PEER certification (in addition to LEED). PEER is a rating system for electricity infrastructure that measures power system performance. Rating systems may address a variety of considerations, including quality assurance, environmental stewardship, long-term viability, financial considerations, accountability and public recognition [8].

While many rating systems rely on certification by an independent agency (e.g., the Green Building Council for LEED certification), there are things the airport can do independently. The ACI created the Airport Carbon Accreditation (ACA) program in 2009 and provided the Airport Carbon and Emissions Reporting Tool (ACERT), which allows airports to conduct their own inventory of their baseline GHG emissions level [21]. Emissions are categorized as Scope 1, 2, or 3, reflecting [21]:

• Emissions by the airport operator (e.g., airport vehicles and terminal HVAC);
• Emissions due to electricity generated offsite and purchased by the airport;
• Emissions in the airport’s supply chain (e.g., airline GSE, vehicles for passengers and employees, and aircraft activity).

ACERT leverages an Excel spreadsheet and can be completed with airport personnel in-house without specialized training by operations, planning, or maintenance staff. ACERT supports ACI’s ACA program, which now includes seven levels [28]:

• Footprint measurement (previously called mapping, reflects an inventory of emissions).
• Carbon management towards a reduced carbon footprint (aka, reduction and reflects actively reducing emissions).
• Third party engagement in carbon footprint reduction (previous optimization, reflects widening the scope to include third party emissions and engagement).
• Carbon neutrality for direct emissions through offsets.
• Transforming airport operations with long term strategy to achieve absolute emissions reductions with cooperation from third parties.
• Compensation for residual emissions with reliable offsets.
• Maintains a net zero balance on scopes 1 (controlled by airport) and 2 (indirect, derived from purchase of energy) and actively addresses scope 3 emissions (life cycle emissions from value chain).

The number of airports that are participating in ACI’s ACA program is shown in Table 2, and the distribution of the participating airports in the US and Europe is shown in Figure 2. Globally, in North America and the US, the majority of airports (88%) are participating at Levels 1, 2, or 3. A participating airport may remain at the same level or may move up to a higher level depending on the local priorities and support. In the US, there are 65 airports in the ACA program; this is significant, but it represents only 17% of the 390 primary airports (as designated in NPIAS). The size of the airport does not necessarily correlate with participation in the ACA program or the level of participation. For example, considering the largest US airports in terms of enplaned passengers, Atlanta (ATL) participates at level 1, and Los Angeles (LAX) participates at level 4. DFW participates at level 4+, and O’Hare does not participate. There are no US airports at level 5. There are 20 airports globally at level 5, although they are not shown in Table 2; three of the level 5 airports are in India (e.g., Indira Gandhi International Airport, DEL), one is in New Zealand (Christchurch Airport, CHC), and the remaining sixteen are in Europe (e.g., Amsterdam Airport Schiphol in the Netherlands, AMS). Sweden and Finland have more level 5 airports than any other countries, with four each (e.g., Stockholm–Arlanda Airport, ARN, in Sweden and Rovaniemi Airport, RVN, in Finland) [29]. As illustrated in Figure 2, Europe has more airports participating in the ACI ACA program and also has a greater percentage of airports in levels 3+, 4, 4+, and 5 (12% in the US and 25% in Europe).

2.2. UN Paris Agreement and Aviation

The highest level of ACI’s ACA program, Transition, reflects alignment with global goals for aviation, such as the climate goals of the UN Paris Agreement signed in 2015. The Paris Agreement aspires to limit carbon dioxide emissions to reduce global warming, and aviation’s goal is carbon neutral growth with a baseline reflecting 2020 emissions levels [30]. Aviation emissions include airport and aircraft emissions, and although airports comprise a small component of total emissions, airports can play an important role in sustainability. Many airports have made great strides to become carbon neutral and support sustainability goals. For aircraft, about 65% of aviation emissions are attributed to international trips and 35% to domestic trips [31]. Overall attainment of aviation goals will be accomplished primarily through carbon offsetting; dozens of airlines have initiated carbon offset programs that reduce or remove carbon through wind energy and other programs (International Air Transport Association) [32]. ICAO’s Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) program supports carbon neutral growth for aviation; participation by member countries is voluntary until 2027, when offset requirements will be required for international routes [33].

Table 2. ACI Airport Carbon Accreditation: Accredited Airports.

Level	Number of Airports			Example Airports in US
	Globally	North America	US
Level 1 Mapping	142	29	20	Hartsfield–Jackson Atlanta International Airport (ATL) Boston Logan International Airport (BOS) Charlotte Douglas International Airport (CLT) Harry Reid International Airport (Las Vegas, LAS)
Level 2 Reduction	197	27	17	Tampa International Airport (TPA) San Antonio International Airport (SAT) George Bush Intercontinental (IAH) Pittsburgh International Airport (PIT)
Level 3 Optimization	154	24	20	Los Angeles International Airport (LAX) Philadelphia International Airport (PHL) Salt Lake City International Airport (SLC) Detroit Metropolitan Airport (DTW)
Level 3+ Neutrality	31	2	1	Austin–Bergstrom International Airport (AUS)
Level 4 Transformation	46	7	5	Phoenix Sky Harbor International Airport (PHX) San Francisco International Airport (SFO) Los Angeles International Airport (LAX) Los Angeles Van Nuys Airport (VNY)
Level 4+ Transition	50	3	2	Dallas–Fort Worth International Airport (DFW) San Diego International Airport (SAN)
Level 5 Net Zero	20			None
Total	640	92	65

Source: [29].

Table 2. ACI Airport Carbon Accreditation: Accredited Airports.

Level	Number of Airports			Example Airports in US
	Globally	North America	US
Level 1 Mapping	142	29	20	Hartsfield–Jackson Atlanta International Airport (ATL) Boston Logan International Airport (BOS) Charlotte Douglas International Airport (CLT) Harry Reid International Airport (Las Vegas, LAS)
Level 2 Reduction	197	27	17	Tampa International Airport (TPA) San Antonio International Airport (SAT) George Bush Intercontinental (IAH) Pittsburgh International Airport (PIT)
Level 3 Optimization	154	24	20	Los Angeles International Airport (LAX) Philadelphia International Airport (PHL) Salt Lake City International Airport (SLC) Detroit Metropolitan Airport (DTW)
Level 3+ Neutrality	31	2	1	Austin–Bergstrom International Airport (AUS)
Level 4 Transformation	46	7	5	Phoenix Sky Harbor International Airport (PHX) San Francisco International Airport (SFO) Los Angeles International Airport (LAX) Los Angeles Van Nuys Airport (VNY)
Level 4+ Transition	50	3	2	Dallas–Fort Worth International Airport (DFW) San Diego International Airport (SAN)
Level 5 Net Zero	20			None
Total	640	92	65

Source: [29].

The 2015 UN Agenda for Sustainable Development also identified 17 Sustainable Development Goals (SDGs) to support sustainable development and ensure peace and prosperity for the planet and its people through partnership [34] (note Planet, People, and Prosperity align closely with the Environment, Social, and Economic framework of TBL). Some of these SDGs are more directly relevant to airports than others, and airport goals vary depending on airport characteristics, activities, and aspirations.

3. Environmental, Social, and Corporate Governance (ESG) and ESG Reporting

A growing interest in airport sustainability reflects the growing interest of society, as evidenced by requirements for ESG reporting initiated in 2005 by the UN Principles for Responsible Investing. ESG reporting is currently required in the European Union (EU) as mandated by the International Sustainability Standard Board; this requirement affects companies headquartered in the EU as well as all companies that transact business in the EU [35]. Given aviation’s global sphere of activity and influence, ESG is becoming increasingly relevant for airlines as well as airports that wish to market their bonds to international investors.

For ESG reporting, environmental factors reflect activities to protect the environment, social factors reflect activities to ensure fair treatment with employees and communities (throughout the supply chain), and governance factors reflect leadership issues, such as diversity, pay, internal controls, and shareholder rights [36]; diversity and pay may also be considered social issues, and there is overlap between the categories. Information contained in ESG reports and ESG ratings developed by investment companies may be considered by investors to assess risks and to align their portfolio with companies that support sustainability goals. ESG ratings developed by investment companies are usually calculated using proprietary methods and reflect information found in ESG reports as well as other information, such as investment risk, due to liability related to environmental harm or employee lawsuits related to discrimination.

3.1. Legal Considerations

Although there have not been any published lawsuits against airports regarding ESG reporting or advertising, some airlines have faced challenges. In September 2023, DWS Investment Management Americas settled an investigation into alleged greenwashing for USD 19 M [37]. Greenwashing refers to entities making misleading claims about sustainability activities or impacts. In this case, the company overstated how ESG data was considered in their investment decisions [37]. Other challenges associated with greenwashing in aviation related to advertising include legal cases against KLM in Dutch court [38] and against Delta, facing a class action suit in Los Angeles due to marketing claims that they are “carbon neutral” [39]. Airlines have also been publicly called out for poor practices without lawsuits. Irish low-cost carrier Ryanair, German carrier Lufthansa, and UAE carrier Etihad have all been recognized for misleading advertising related to environmental claims [39], including Ryanair’s claim to be Europe’s lowest emission airline, Lufthansa’s claim to be protecting the future, and Etihad’s use of the term sustainable aviation. Airlines were told to avoid wording that could imply their activities were good for the environment since airline travel is a significant contributor to consumer carbon impacts. These examples illustrate that the impact of sustainability claims extend beyond communication and marketing [39].

Airports are also affected by public concerns about sustainability and have been subject to protests, which can be very disruptive. Members of a climate activist group have protested on the runway at Frankfurt Airport, disrupting airport operations and resulting in cancellation of over one hundred flights [40]. Other airports have also faced disruption and attempted disruption, including Munich Airport, Helsinki Vantaa Airport, Barcelona El Prat Airport, London Heathrow, and Oslo’s Gardermoen Airport [41]. Disrupting airport operations for even a short period of time can be expensive and incur significant costs for the airport as well as for airlines, passengers, and air freight. Disruptions to airport revenues from operational issues is of interest to airport management as well as holders of airport bonds.

Many airports issue bonds to fund infrastructure projects. In some cases, the airport sponsor and bond issuer is a municipality, such as a city or county; in other cases, the airport sponsor and bond issuer is a public corporation, such as an airport authority. The US Securities and Exchange Commission (SEC) does not regulate disclosure requirements for municipal securities (per the Tower Amendment); however, municipal issuers are still obligated to meet antifraud standards and must disclose material facts that could affect investment decision [42]. The SEC also requires brokers and dealers to provide information, although there is no required format as there is for regulated corporate securities [42]. Although the obligations and liability of airport sponsors may be limited, there are still concerns regarding the potential liability associated with ESG reports; for this reason, airports may elect not to publish an ESG report.

This may be one reason many US airports publish a sustainability report rather than an ESG report. Sustainability reports often highlight airport activities and are a good communication tool to support community and public relations. Sustainability reports allow airports to present any information they wish (including qualitative or quantitative information) and may incur less liability related to implications for investment decisions or material facts, including compliance with security laws for complete and accurate reporting.

Regulations regarding ESG reporting are likely to continue to evolve. On 6 March 2024, the SEC adopted rules that require disclosure of climate-related information in annual statements and other required financial reports for public companies that are filed with the SEC beginning 31 December 2025; this ruling affects both US and foreign private issuers [43]; however, this rule may be changed by the new presidential administration. This rule does not affect municipal issuers, so most airports are not directly affected; however, it provides a leading indicator regarding how the SEC may address the issue in the future and illustrates increasing interest in ESG reporting. There have been legal challenges to this rule by a coalition of ten states that allege it presents an undue burden [44] and by environmental groups that allege it does not go far enough. In the long term, the disparity of reporting requirements in different countries may be addressed by international efforts, such as the G20 Sustainable Finance Roadmap, which was developed to support global standards assessment and management of climate and sustainability [45].

There is no “standard” practice for ESG reporting or for sustainability reporting for US airports, however, there are a number of reporting frameworks on which to build. ACI identified ESG management best practices for airports in 2022 and found that most airports used, “sustainability reporting frameworks such as the Global Reporting Initiative (GRI), Sustainable Accounting Standards Board (SASB), and B Corporation, and aspect specific tools such as ACA, and the Carbon Disclosure Project (CDP) for reasons such as annual reporting, stakeholder/investor engagement, and communicating their corporate strategy” [46].

3.2. Global Reporting Index (GRI)

GRI provides a framework to assess ESG and has been used for many years to report corporate sustainability efforts, with information often compiled by consultants, such as KPMG. GRI standards reflect corporate activities for the areas of governance, economic, environmental, and social impacts. GRI has developed a framework for airport operators; this framework has been used by the Metropolitan Washington Airports Authority (MWAA) for Ronald Reagan National Airport (DCA) and Dulles International Airport (IAD) [47]. The GRI is also used by international airports, such as Amsterdam Airport Schiphol [48] and Sydney Airport, which references the GRI Core Option and also reports in accordance with SASB Standards and the Business for Societal Impact for community investment [49].

3.3. Sustainable Accounting Standards Board (SASB)

SASB was created to support standard disclosures to support ESG topics and reporting. SASB provides sustainability accounting standards for 11 sectors, including the transportation sector, although there are no accounting standards targeted specifically for airports. SASB is not widely used in the US by airports; however, it is used by some airports in other countries, including Aukland International Airport and the Beijing Capital International Airport [50]. For example, the SASB primary sustainable industry classification system (SICS) sector and primary SICS industries for airport providers include services, professional and commercial (used by Aukland International Airport Ltd., Auckland, New Zealand), and infrastructure, engineering and infrastructure services (used by Beijing Airport High-Tech Park Co., Ltd., Beijing, China). Other airport sectors and industries include food and beverage, restaurants (used by Noi Bai Airport Services, JSC, Hanoi, Vietnam), and resource transformation, industrial machinery and goods (used by Weihai Guangtai Airport Equipment Co., Ltd., Weihai, China) [50].

3.4. International Integrated Reporting Council (IIRC)

IIRC does not provide guidelines for reporting ESG performance; however, it does support the development of key performance indicators or KPIs. This framework has been used by Airports Company South Africa [51] and may be more relevant for airports run by companies, given the focus on connecting the ESG report with strategy, management, and financial performance. Airports Company South Africa is a company with legal and financial autonomy and majority ownership by the South African Government (much like Royal Schiphol, the owner of Amsterdam Airport Schiphol and other airports).

3.5. Carbon Disclosure Project (CDP)

The Carbon Disclosure Project (CDP) is a global non-profit that focuses on reporting and curbing carbon emissions [52]. It includes disclosure information about risks, opportunities, governance, environmental performance, and financial services. The environmental performance includes information about climate change, forests, water security, plastics, and biodiversity [52].

3.6. B Corporation

B Corporation provides certification for social impact, including social sustainability, environmental performance, accountability, and transparency [53] (B Lab, 2024). No airports in the US have been certified as a B Corporation (aka B Corp), and there is no associated legal status or due diligence. There have been criticisms that its greatest use is for corporate branding.

3.7. ACI

In addition to the ACA and ACERT [28] previously discussed, ACI has developed “Sustainability Strategy for Airports Worldwide” to identify topics that are common to all airports based on an assessment of 80 airports and reported across the three pillars of sustainability (economic, environmental, and social) [22]. Each topic is accompanied by a brief introduction, its relevance to sustainability at an airport level, its contribution to the SDGs, and key examples of leading initiatives undertaken by airport operators. The results of this analysis are shown in Table 3 and Table 4, which highlights the contribution of each pillar to each SDG.

Some of the material issues shown in Table 3 are commonly reported by airports. For example, the direct and indirect economic impact of airports is often reported by airports and state airport system plans. These direct and indirect economic impacts align closely with SDG 8 Decent Work and Economic Growth, SDG 9 Industry, Innovation, and Infrastructure, and SDG 11 Sustainable Cities and Communities. The positive contribution of airports to the economy also would support SDG 1 No Poverty; however, most airports do not track or report the local poverty rate. SDG 1 No Poverty, SDG 8 Decent Work and Economic Growth, SDG 9 Industry, Innovation, and Infrastructure, and SDG 11 Sustainable Cities and Communities are also supported by the social pillar. This may reflect the impact of the airport both on employees as well as community members. SDG 3 Good Health and Well Being is addressed by all three of the pillars at airports. This may reflect operational practices that support the health and well-being of airport employees as well as environmental initiatives, such as noise reduction that have a positive impact on airport neighbors and community members. Some airports are also now considering passenger health in the design of their airports (e.g., as evidenced by the use of the WELL rating system). Initiatives to reduce the environmental impact of airports also supports SDG 11 Sustainable Cities and Communities for all three pillars. Many of the activities related to environmental mitigation are attributed solely to the environmental pillar, including SDG 6 Clean Water and Sanitation, SDG 7 Affordable and Clean Energy, SDG 12 Responsible Consumption and Production, SDG 13 Climate Action, SDG 14 Life Below Water, and SDG 15 Life on Land. These SDGs are supported by waste management programs and the use of renewable energy. Supporting SDG 17 Global Partnerships to Support Sustainability Goals is not included in the ACI Sustainable Strategy for Airports.

ACI has initiated a project to improve ESG reporting for airports, and the Netherlands Airport Consultants (NACO) and To70 have been hired to develop a standardized framework; however, the results of this effort have not been published [54].

3.8. World Economic Forum (WEF)

Although there are not standard reporting requirements for ESG in the US for airports, there have been suggestions that are appropriate for consideration by airports. Table 5 provides one possible framework based on information from the WEF in collaboration with Deloitte, EY, KPMG, and PwC [55]. This table presents four pillars that support sustainable development, principles of governance, planet, people, and prosperity, as well as the SDGs that these principles align with, recommendations for the kind of disclosure that would be appropriate, example metrics, and how this might apply for an airport. Both the ACI and the WEF framework reference suggested SDGs, although they are conceptual rather than proscriptive. ACI references material issues, which may be somewhat analogous to GRI’s material topics.

Table 3. ACI Sustainable Strategy for Airports.

Sustainability Pillar	Material Issue	Example Application for Airport	Related SDGs
Economic Use resources effectively to sustain operations and support the economy (and maybe return a profit)	Direct economic impact	Aviation contributes 4.1% of global GDP	1 No Poverty 3 Good Health and Well Being 8 Decent Work and Economic Growth 9 Industry, Innovation, and Infrastructure 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 16 Peace, Justice, and Strong Institutions
	Indirect and induced economic impact	Collaborate with local firms to support local supply chain
	Market presence and connectivity	Over 48,000 routes globally
	Sustainable supply chain	Consider lifetime costs for procurement
	Anti-corruption	Use data analytics to identify high-risk transactions and provide appropriate control
Social Contribute to well-being of society by supporting employees, customers, and the local community	Community and noise	Noise monitoring and mitigation through operating policies	1 No Poverty 2 Zero Hunger 3 Good Health and Well Being 4 Quality Education 5 Gender Equality 8 Decent Work and Economic Growth 9 Industry, Innovation, and Infrastructure 10 Reduced Inequalities 11 Sustainable Cities and Communities 16 Peace, Justice, and Strong Institutions
	Service quality	Provide current information to passengers
	Employment	Provide skill development for potential employees in community
	Health and safety	Employee initiatives for healthy lifestyles
	Diversity and equity	Inclusive recruitment fairs to support employees with disabilities
Environmental Consume natural resources at a sustainable rate and limit damaging activities	Climate change	Reduce emissions	3 Good Health and Well Being 6 Clean Water and Sanitation 7 Affordable and Clean Energy 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 13 Climate Action 14 Life Below Water 15 Life on Land
	Energy and emissions	Use renewable energy
	Water and effluents	Minimize water usage and use water saving technologies
	Waste management	Waste management and reduce, reuse, recycle
	Biodiversity	Protect local habitats

Source: [22,56].

Table 3. ACI Sustainable Strategy for Airports.

Sustainability Pillar	Material Issue	Example Application for Airport	Related SDGs
Economic Use resources effectively to sustain operations and support the economy (and maybe return a profit)	Direct economic impact	Aviation contributes 4.1% of global GDP	1 No Poverty 3 Good Health and Well Being 8 Decent Work and Economic Growth 9 Industry, Innovation, and Infrastructure 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 16 Peace, Justice, and Strong Institutions
	Indirect and induced economic impact	Collaborate with local firms to support local supply chain
	Market presence and connectivity	Over 48,000 routes globally
	Sustainable supply chain	Consider lifetime costs for procurement
	Anti-corruption	Use data analytics to identify high-risk transactions and provide appropriate control
Social Contribute to well-being of society by supporting employees, customers, and the local community	Community and noise	Noise monitoring and mitigation through operating policies	1 No Poverty 2 Zero Hunger 3 Good Health and Well Being 4 Quality Education 5 Gender Equality 8 Decent Work and Economic Growth 9 Industry, Innovation, and Infrastructure 10 Reduced Inequalities 11 Sustainable Cities and Communities 16 Peace, Justice, and Strong Institutions
	Service quality	Provide current information to passengers
	Employment	Provide skill development for potential employees in community
	Health and safety	Employee initiatives for healthy lifestyles
	Diversity and equity	Inclusive recruitment fairs to support employees with disabilities
Environmental Consume natural resources at a sustainable rate and limit damaging activities	Climate change	Reduce emissions	3 Good Health and Well Being 6 Clean Water and Sanitation 7 Affordable and Clean Energy 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 13 Climate Action 14 Life Below Water 15 Life on Land
	Energy and emissions	Use renewable energy
	Water and effluents	Minimize water usage and use water saving technologies
	Waste management	Waste management and reduce, reuse, recycle
	Biodiversity	Protect local habitats

Source: [22,56].

Table 4. Alignment of UN SDGs with sustainability pillars in the ACI Sustainable Strategy for Airports.

UN SDG		Economic	Social	Environmental	Not Included
1	No Poverty	√	√
2	Zero Hunger		√
3	Good Health and Well Being	√	√	√
4	Quality Education		√
5	Gender Equality		√
6	Clean Water and Sanitation			√
7	Affordable and Clean Energy			√
8	Decent Work and Economic Growth	√	√
9	Industry, Innovation, and Infrastructure	√	√
10	Reduced Inequalities	√	√
11	Sustainable Cities and Communities	√	√	√
12	Responsible Consumption and Production			√
13	Climate Action			√
14	Life Below Water			√
15	Life on Land			√
16	Peace, Justice, and Strong Institutions	√	√
17	Global Partnerships for Goals				√

Table 4. Alignment of UN SDGs with sustainability pillars in the ACI Sustainable Strategy for Airports.

UN SDG		Economic	Social	Environmental	Not Included
1	No Poverty	√	√
2	Zero Hunger		√
3	Good Health and Well Being	√	√	√
4	Quality Education		√
5	Gender Equality		√
6	Clean Water and Sanitation			√
7	Affordable and Clean Energy			√
8	Decent Work and Economic Growth	√	√
9	Industry, Innovation, and Infrastructure	√	√
10	Reduced Inequalities	√	√
11	Sustainable Cities and Communities	√	√	√
12	Responsible Consumption and Production			√
13	Climate Action			√
14	Life Below Water			√
15	Life on Land			√
16	Peace, Justice, and Strong Institutions	√	√
17	Global Partnerships for Goals				√

ESG evaluators use various data collection methods to gather insights on ESG performance of companies; insight may be gained by conducting analysis of publicly available information and ESG reports (which are often prepared using ESG reporting guidelines) as well as by directly interviewing companies of interest. Financial institutions often use their own systems to evaluate the ESG of an organization and rating agencies rarely publicly disclose their ESG assessment methodology and metrics, which are considered proprietary information. Standard reporting requirements and disclosure may help rating companies assess risks related to ESG and balance these risks with the expected benefits.

Table 5. World Economic Forum (WEF) pillars to support sustainable development.

Four Pillars to Support to UN Sustainable Development Goals (SDG) 1	Suggested SDG for Alignment 1,2	Disclosure Recommendations 1,2	Example Metrics 1	Example Application for Airports
Principles of Governance Reflect principals of agency, accountability, and stewardship	12 Responsible Consumption and Production, 16 Peace, Justice, and Strong Institutions, 17 Partnership to achieve SDGs.	Company’s commitment to ethics and the societal benefits it offers.	Board composition	Independence of board Board reflects stakeholders and community
			Stakeholder engagement	Process to receive and respond to stakeholder input
			Ethical Behavior	Ethics training for all employees Mechanism for reporting ethical concerns Manage conflicts of interest
Planet Practice sustainable consumption, production, and management	6 Clean Water and Sanitation, 7 Affordable and Clean Energy, 12 Responsible Consumption and Production, 13 Climate Action, 14 Life Below Water, 15 Life on Land.	Company’s climate sustainability and environmental responsibility matters.	Greenhouse gas (GHG) emissions and air pollution	GHG for airport activities and airport operations and transportation to the airport 3 Fine particulate matter (PM2.5)
			Land use	Noise impacts on adjacent properties
			Fresh water availability	Impact on water quality (e.g., PFAS)
People Ensure people can fulfill their potential in a healthy environment; end poverty and hunger.	1 No Poverty, 3 Good Health and Well-Being, 4 Quality Education, 5 Gender Equality, 8 Decent Work and Economic Growth 4, 10 Reduced Inequalities.	Company’s activities to ensure a safe and healthy workforce that reflects equitable access.	Equality	Gender pay equity Extent to which employee workforce reflects local population
			Health and well-being	Employee recordable injury rate Employee absentee rate Public health impacts for airport neighbors
			Skills for the future	Training provided
Prosperity All people enjoy prosperous and fulfilling lives and economic, social, and technological progress is in harmony with nature.	1 No Poverty, 8 Decent Work and Economic Growth, 9 Industry, Innovation, and Infrastructure, 10 Reduced Inequalities.	Company’s business contributions to equitable, innovative growth.	Employment and wealth generation	Number of jobs created Net economic contribution
			Innovation	Spending on R&D
			Community and social vitality	Community partnerships and investments

¹ Source: [55]. ² Source: [57]. ³ GHG for transportation to the airport and airport operations have historically been excluded; however, trends to require consideration of the entire supply chain suggest this will be an appropriate consideration in the future. ⁴ SDG 8 is included in the people pillar example by Kuratek et al. [57] but not in the WEF document [55].

Table 5. World Economic Forum (WEF) pillars to support sustainable development.

Four Pillars to Support to UN Sustainable Development Goals (SDG) 1	Suggested SDG for Alignment 1,2	Disclosure Recommendations 1,2	Example Metrics 1	Example Application for Airports
Principles of Governance Reflect principals of agency, accountability, and stewardship	12 Responsible Consumption and Production, 16 Peace, Justice, and Strong Institutions, 17 Partnership to achieve SDGs.	Company’s commitment to ethics and the societal benefits it offers.	Board composition	Independence of board Board reflects stakeholders and community
			Stakeholder engagement	Process to receive and respond to stakeholder input
			Ethical Behavior	Ethics training for all employees Mechanism for reporting ethical concerns Manage conflicts of interest
Planet Practice sustainable consumption, production, and management	6 Clean Water and Sanitation, 7 Affordable and Clean Energy, 12 Responsible Consumption and Production, 13 Climate Action, 14 Life Below Water, 15 Life on Land.	Company’s climate sustainability and environmental responsibility matters.	Greenhouse gas (GHG) emissions and air pollution	GHG for airport activities and airport operations and transportation to the airport 3 Fine particulate matter (PM2.5)
			Land use	Noise impacts on adjacent properties
			Fresh water availability	Impact on water quality (e.g., PFAS)
People Ensure people can fulfill their potential in a healthy environment; end poverty and hunger.	1 No Poverty, 3 Good Health and Well-Being, 4 Quality Education, 5 Gender Equality, 8 Decent Work and Economic Growth 4, 10 Reduced Inequalities.	Company’s activities to ensure a safe and healthy workforce that reflects equitable access.	Equality	Gender pay equity Extent to which employee workforce reflects local population
			Health and well-being	Employee recordable injury rate Employee absentee rate Public health impacts for airport neighbors
			Skills for the future	Training provided
Prosperity All people enjoy prosperous and fulfilling lives and economic, social, and technological progress is in harmony with nature.	1 No Poverty, 8 Decent Work and Economic Growth, 9 Industry, Innovation, and Infrastructure, 10 Reduced Inequalities.	Company’s business contributions to equitable, innovative growth.	Employment and wealth generation	Number of jobs created Net economic contribution
			Innovation	Spending on R&D
			Community and social vitality	Community partnerships and investments

¹ Source: [55]. ² Source: [57]. ³ GHG for transportation to the airport and airport operations have historically been excluded; however, trends to require consideration of the entire supply chain suggest this will be an appropriate consideration in the future. ⁴ SDG 8 is included in the people pillar example by Kuratek et al. [57] but not in the WEF document [55].

The need to balance risks and negative impacts with benefits is analogous to the balanced perspective required when considering aviation sustainability in general. The negative environmental impacts of aviation must be carefully considered and balanced with the many benefits of aviation, including increased mobility and economic necessity. Aviation is a powerful economic engine that moves people and goods, and aviation is critical to many local economies as well as the global supply chain. Recognizing the importance of aviation to a robust economy, in 2024, Swedish Infrastructure Minister Andreas Carlson recently announced the end of flygskam (aka flight shaming), which began in 2018 [58]. Although the social movement of flygskam cannot simply be dissolved by an announcement by a government official, his announcement was not empty rhetoric; it was paired with an investment of USD 97 M for airport security screening [58]. These funds were required due to funding gaps associated with reduced travel since COVID. In Sweden and other places, air travel is critical not only for economic reasons but also to ensure the movement of goods and people in remote areas and for trips that cannot be served by other modes.

4. Methodology

The purpose of this research is to present information about ESG reporting practices for large hub airports in the United States. The data used are ESG reports published by large hub US airports that are available on the internet. The data collection process included retrieval of sustainability and ESG reports from the websites of large hub US airports in 2024.

Initial analysis included whether the airport published the report as an ESG report. If the airport did not publish an ESG report (as designated by the title), then it was noted whether they published a sustainability report or sustainability plan or another sustainability resource.

The ESG reports for the large hub airports were then reviewed in detail, and information about the reports was tabulated, with consideration to the kind of information included in the report and references to the use of rating systems related to sustainability.

Case studies with more detailed reporting information are provided for Salt Lake City Airport (SLC) and for Dallas–Fort Worth Airport (DFW), the two large hub airports that explicitly reference the UN SDGs in their ESG reports. These two airports were selected because they represent different characteristics in terms of size, administrative structure, and legacy use of ESG reporting. In terms of size, they are neither the smallest nor largest large hub airport in terms of enplanements but provide differing perspectives with SLC on the smaller side, with 12.9 M passenger enplanements, and DFW on the larger side, with over 39 M passenger enplanements. In terms of organizational structure, SLC is a city-owned airport, and DFW is governed by an airport board that is owned by two cities, Dallas and Fort Worth. In terms of ESG reporting experience, SLC is relatively new to ESG reporting, with their first ESG report published in 2021, and DFW was the first US airport to publish an ESG report in 2016. Examination of these two case studies provides a more thorough perspective on the contents of an ESG report at a large US hub airport. The two airports are qualitatively assessed based on the 20 recommended disclosure elements recommended for inclusion in ESG reports as identified by ACI-NA [59]. The twenty recommended disclosure elements are as follows:

Environmental

• Energy consumption;
• Energy intensity;
• Greenhouse gas emissions (GHG) Scope 1 and 2;
• GHG intensity—Scope 1 and 2;
• Climate risk exposure and adaptation;
• Environmental commitments and progress;
• Environmental non-compliance;
• Waste management;
• Water management;

Social

• Diversity, equity, and inclusion (DEI)—workforce ethnicity and gender;
• Business supplier diversity (DBE/MWBE);
• Concessionaire diversity (ACDBE);
• Workplace/employee safety;

Governance

• Governance/organizational structure;
• Board of directors’ background/ diversity;
• Executive management background/diversity;
• Approach to risk management;
• Cybersecurity—general discussion;
• Reporting and transparency;
• Ethics and compliance.

For each of the 20 disclosure elements, the report is scored from 0 to 3, with a score of 0 when no information is included, a score of 1 when there is minimal information, a score of 2 if a metric is included and reported, and a score of 3 if the metric includes data for multiple years; the resulting highest possible score is 60. This facilitates additional comparison between the ESG reporting for the two airports.

It is also helpful to consider how ESG reporting for these airports compares to a larger context. One method used to address this issue is a comparison of the UN SDGs addressed in the SLC and DFW ESG reports with the frameworks presented by the WEF and ACI. A second way this is addressed is by comparing SLC and DFW ESG reports with sustainability reports for Sydney Airport and the Schiphol Airport Group. This comparison includes SDGs as well as stakeholders that were involved, the standards used, and the disclosure of information that is not favorable. Since all airports have been faced with the issue of possible PFAS (per- and polyfluoroalkyl substances) contamination due to the historic use of aqueous firefighting foam (AFFF) at airports, the inclusion of issues related to PFAS in the report was assessed. AFFF is very effective at fighting aircraft fires, and it was not until relatively recently that PFAS was recognized as a health hazard and environmental concern.

5. Results: Analysis of US Airport ESG Reports for Large Hub Airports

Despite substantial movement toward corporate ESG reporting, US airports have been slower to adopt ESG reporting, as shown in

Table 6. Sustainability reporting for NPIAS large hub airports.

Airport Code	Airport	ESG Report?	Example Sustainability Report or Plan or Resource	Year	Reference
ATL	Hartsfield–Jackson Atlanta Intl	Yes	Future Forward: Environmental, Social, Governance + Prosperity Report	2023	[63]
AUS	Austin-Bergstrom Intl	Yes	AUS ESG Environmental Social Governance Report Fostering Sustainable Growth, Innovation, and Resilience	2023	[64]
DCA DUL	Ronald Reagan Washington NationalWashington Dulles Intl	Yes Yes	2023 Environment, Social and Governance Impact Report	2023	[47]
DEN	Denver Intl	Yes	Denver International Airport Environmental, Social and Governance Report 2022	2022	[65]
DFW	Dallas–Fort Worth Intl	Yes	Creating a Sustainable Tomorrow, Today 2023 Environmental, Social and Governance Report	2023	[66]
SLC	Salt Lake City Intl	Yes	SLC International ESG Environmental Social Governance Report Published 2023 Reporting Period 2021–2022	2023	[67]
PHL	Philadelphia Intl	Yes	Environmental, Social, and Governance Report PHL PNE Philadelphia International Airport, Northeast Philadelphia Airport	2022	[68]
BOS	General Edward Lawrence Logan Intl	No	2020/2021 Massport Sustainability and Resiliency Report	2020–2021	[69]
BNA	Nashville Intl	No	Sustainable Master Plan Pilot Program	2020	[70]
BWI	Baltimore/Washington Intl Thurgood Marshall	No	Green Promotion and Reporting Program	2022	[71]
CLT	Charlotte/Douglas Intl	No	City of Charlotte Aviation Department Comprehensive Sustainability Plan	2020	[72]
DET	Detroit Metro Wayne County	No	Wayne County Airport Authority Sustainability Program	2017	[73]
EWR JFK LGA	Newark Liberty Intl John F Kennedy Intl LaGuardia	No	Net Zero Roadmap Sept 2023 Interactive educational program toolkit Youtube videos
		No		2023	[62]
		No
FLL	Fort Lauderdale/ Hollywood Intl	No	Green Airport Initiative		[74]
HOU	George Bush Intcntl/ Houston	No	Sustainable Management Plan 2018	2018	[75]
LAS	Harry Reid Intl	No	Website		[76]
LAX	Los Angeles Intl	No	2022 Sustainability Report LAWA	2022	[77]
MDW	Chicago Midway Intl	No	Sustainable airport manual (SAM)	2020	[60]
ORD	Chicago O’Hare Intl	No
MCO	Orlando Intl	No	Sustainability management plan 2014–2020 and other reports		[78]
MIA	Miami Intl	No	Webpage		[79]
MSP	Minneapolis-St Paul Intl/ World-Chamberlain	No	Sustainability Annual Report (meets state legislative obligation)	2024	[80]
PHX	Phoenix Sky Harbor Intl	No	2022 sustainability Management Plan Update	2022	[81]
SAN	San Diego Intl	No	2022–2023 Sustainability and DEI Report	2023	[61]
SEA	Seattle-Tacoma Intl	No	Environment and Sustainability report 2023 Annual Report	2023	[82]
SFO	San Francisco Intl	No	2023 Zero Annual Report: SFO’s Journal to Zero	2023	[83]
TPA	Tampa Intl	No	2024 Sustainable Management Plan	2024	[84]

. Only 8 of the 30 NPIAS large hub airports have published ESG reports. However, this does not indicate a lack of interest in sustainability, as all airports in Table 6 provide information on their sustainability efforts. For example, the Chicago Department of Aviation (CDA) has published a Sustainable Airport Manual (SAM) with more than 500 pages of guidance [60]. The current manual (the fourth version) reflects a strong and long-time interest in sustainability as well as partnerships, as evidenced by endorsement from the USGBC and US EPA. Another example of an airport that has a strong commitment to sustainability reporting is the San Diego Airport (SAN). Although The Sustainability and DEI report published by SAN is not labeled as an ESG report, it us very comprehensive, reflects consistency with GRI metrics and alignment with SDGs, presents extensive data, and provides general standard disclosures [61]. In addition to airport sustainability reports and websites, the Port Authority of New York and New Jersey (PANYNJ) publishes videos and educational toolkits to support an understanding of their sustainability activities [62].

There are a wide variety of sustainability resources published by airports, and there is also a wide variety of information presented in sustainability reports, including ESG reports.

Table 7. Example topics addressed in ESG reports for large hub airports in the US.

	PHL	DCA and DUL	DEN	SLC	ATL	AUS	DFW
Airport Information
Enplanements (2023)	23,880,504	DCA: 12,365,030 DUL: 12,073,571	37,863,967	12,905,368	50,950,068	10,833,443	39,246,212
Sponsor	City	Airport Authority	City and County	City	City	City	Cities of Dallas and Fort Worth (governed by Airport Board)
Topics in ESG Report
Solar power	Yes	Yes	Yes	Yes	Yes	Yes	Yes
EV	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Hybrid Vehicles	No	Yes	No	No	No	No	No
LEED	Yes	No	Yes	Yes	Yes	Yes	Yes
ACA	Yes	No	Yes	Yes	Yes	Yes	Yes
Scope 1, 2, 3 Emissions	Yes	No	Yes	Yes	Yes	Yes	Yes
Envision	No	No	Yes	No	Yes	No	No
Green concessions	No	Yes	No	No	No	No	No
SDG	No	No	Yes, but not explicit	Yes	No	No	Yes
GRI	No	Yes	Yes, but not explicit	No	No	Yes, but not explicit	Yes, but not explicit
SASB	No	No	Yes, but not explicit	No	No	No	No
Noise	Yes	No	Yes	Yes	Yes	No	Yes
Demographic characteristics	Workforce gender and race/color	Board by gender and race/ethnicity	Firms by gender and ethnicity; Employees by gender, generation, and race	Employees by gender and white/color	Board gender, color/race, and average age	Employees by gender and race/color	DFW workforce by gender and color
NREL	No	Yes	No	No	No	No	Yes
Human trafficking	No	Yes	No	Yes	Yes	Yes	Yes

Sources: PHL [68], DCA and DUL [47], DEN [65], SLC [67], ATL [63], AUS [64], DFW [66].

provides additional information about the information provided in the ESG reports by large hub airports. This is not intended to be a comprehensive assessment of content but to illustrate that each airport has a different approach to sustainability and sustainability reporting. All airports in Table 7 reported some activities with solar power and EVs, and all airports reported some demographic data (e.g., gender, race and/or color), whether associated with employees, contractors, or the sponsor board. The reporting of demographic data illustrates how information related to diversity, equity, and inclusion (DEI) has often become a component of sustainability reporting, and it may be included in either the social pillar, representing employees, in the economic pillar, representing contractors, and/or in the governance pillar, representing leadership. Certification information, such as LEED and ACA (and associated reporting of emissions), was mentioned in many of the ESG reports; Envision was less often referenced. Although not shown in the table, local certification may also be used.

For example, Denver Airport (DEN) uses local certification for concessions and Colorado Green Businesses through the Certifiably Green Denver (CGD) a city-wide program [65]. Reporting frameworks, such as SDG and GRI, were mentioned in some cases; sometimes there was explicit mapping to specific elements (e.g., SLC mapped specific components to SDGs [67]), and in other cases, there was just a general statement that these frameworks were considered in the development of the report (e.g., the Denver report mentioned that the SDGs, GRI, and SASB were all considered, but there was no explicit or detailed mapping or reporting [65]). Austin Airport (AUS) and Dallas–Fort Worth Airport (DFW) also acknowledged that GRI informed the report [64,66], whereas the report for DCA and DUL included a content index that mapped sections of the report (e.g., introduction, social, governance, environment) to specific GRI General Disclosures (e.g., GRI 102-15, Conflicts of Interest) and Material Topics (e.g., GR 204-1, Supplier Diversity, a component of Economic Performance) [47]. Many airports mention awards they have received, which include airport awards as well as local awards; these awards are often related to the environmental component and may reflect initiatives related to clean energy, but they also may be related to the social component, such as Austin Airport’s (AUS) awards for reflecting the local culture [64]. Some airports mentioned local partners for activities (e.g., local charities and local utilities), and some mention national partners, such as NREL, the National Renewable Energy Lab. Other partners may include government agencies, such as the Department of Transportation and the Department of Homeland Security to combat human trafficking through programs, such as the Blue Lightning Initiative; however, not all airports report involvement in this. The SLC mentions their participation in the program in the ESG [67] but does not feature human trafficking as prominently as ATL [63]. DFW mentions human trafficking but only in the context of a charitable drive to support survivors [66]. Due to a lack of standards for US airport ESG reporting, an omission in the ESG report does not necessarily imply that an activity does not occur.

Table 8. Major topics in ESG reports for large hub airports in the US (per the table of contents).

	PHL	DCA and DUL	DEN	SLC	ATL	AUS	DFW
Introduction
Summaries	Airport summaries	About MWAA	About DEN	Introduction	√	The airport	About DFW; DFW by the numbers
Leadership	√	√	DEN leadership	√	√	√	Leadership and strategy
Mission and Vision	Mission and vision	√	√	√	√	Core values/ vision/mission	√
Strategic Planning	Strategic planning in governance		Strategic planning	Strategy	√	√	√
Awards and Recognition	Awards and recognition	√	Key figures and awards	√	√	√	√
Approach to ESG Reporting	Approach to ESG reporting		ESG reporting	ESG reporting	About ATL’s ESG + P report	ESG approach and process; Materiality approach	2023 ESG highlights
History	√	Year in review		Our history and journey			Year in review
Other	Market position			Transparency
Environment
Sustainability	Sustainability and environmental management	Innovation in sustainability	Sustainable development	Sustainability	√	√	√
Air Quality	Air quality; Managing our carbon footprint	Emissions reduction	Air quality and climate	Greenhouse gas emissions	√	Greenhouse gas emissions	√
Climate	Building toward climate resistance		√	Climate risks and biodiversity	Climate and resilience	Climate resilience and adaption	Climate action
Biodiversity and Natural Resources	Conserving and protecting our natural resources			√	Biodiversity and conservation	Wildlife protection and biodiversity	√
Waste	Working toward zero waste	Waste management	Waste reduction and diversion	Waste	Waste recovery and diversion	Waste and recycling	Zero waste and circular economy
Energy	√	Energy efficiency	Energy	√	√	Energy; Spotlight on alternative fuels	Energy performance
Water	Stormwater management	Water stewardship	Water quality and use	Water	Water quality and conservation	Water resources	Water and biodiversity
Procurement		√	√		Procurement and supply chain	Procurement and resource management	√
Other			Land management; Aircraft noise		Environmental compliance
Social
DEI and inclusive business	Diversity, equity and inclusion; Inclusive business	Diversity and inclusion	Equality, diversity inclusion and accessibility	Diversity, equity and inclusion; DBE participation	√	Diversity, equity and inclusion	√
Employees	Employee wellness	Our People, Employee, health, safety, well-being	Employee investment and engagement;	Employee health and wellness; Education; Training	Employee benefits and professional development	Hiring and retention, Health/ wellness and safety; Healthy connections	Employees
Safety and Security	Safety and security	Safety and security	Safety and security	Employee background and safety	Safety and security	√	Safety and security
Customers	Guest experience; Accessibility	Customers	Customer experience	User experience	Service quality and accessibility	User experience; Healthy here, healthy there (COVID testing)	√
Community	Community outreach and impact	Community engagement	√	Engagement and outreach	Community relations	Stakeholder and community outreach	Community
Other	Noise management		Denver wage laws	Economic impact	Human trafficking
Governance
Airport and Board	Organizational structure	Governance structure	Airport operations	Airport structure; Airport advisory board	Oversight, structure, and strategy	Structure and oversite; AUS ESG commitment	Governance structure
Risk	Risk management	√	Risk management and emergency preparedness	Risks	Enterprise risk management	Risk and emergency management	Risk management
Cybersecurity	Cybersecurity	Cybersecurity	Cybersecurity and privacy	√	√	√	√
Innovation	Innovation	√	√	Innovation, infrastructure, and facilities	√	Innovation	√
Planning	Strategic planning	√	Growth and expansion	√	√	√	√
Financial Reporting	Financial reporting and disclosure	√	Financial performance	√		Financial performance	Reporting, transparency, and assurance
Ethics	√	Transparency, ethics, integrity	Ethics and conflicts of interest		√	Accountability and transparency	√
Service		√	Continuous improvement	√	√	Service and market performance	√
Economic Impact		Economic performance	√	Economic performance	√	√	√
Infrastructure		√	√	√	Infrastructure and facilities	infrastructure and facilities	√
Data management			√	√	Asset and data management	Cyber risks and data management	√
Prosperity					Economic engine; International affairs; Business diversity; Hiring goals; Living wage; Innovation
Look Ahead	Look ahead		A look ahead	Looking ahead	Look ahead	ESG—A Look forward
Data		GRI content index		Data analytics tables

Text indicates heading in report, √ indicates the topic is discussed but not a primary heading. Sources: PHL [68], DCA and DUL [47], DEN [65], SLC [67], ATL [63], AUS [64], DFW [66].

provides an overview of the prominent topics featured in the ESG reports by large hub airports. The text information in this table reflects headings in the table of contents for each ESG report; while it does not provide exhaustive information about the contents, it does illustrate topics that airports wish to highlight or feature. Checks indicate there was information included about the topic, although there was not a section devoted to the topic. For example, although ATL does not highlight its mission and vision and leadership as a primary topic in the table of contents, it includes information about the mission and vision and leadership in sidebars and in the narrative, so there is a check [63].

Similarly, ATL participates in ACA and reports Scope 1 and 2 emissions, but it does not devote a section to air quality [63]. ATL does put a strong emphasis on prosperity and is the only airport to publish an Environmental, Social, Governance + Prosperity Report, including information about economic impacts, wages, and innovation in the Prosperity section. While other reports include similar information, it is included in other sections, such as the Social section (employee wage information) or Governance section (economic impact). In this case, review of the information in Table 8 provides insight into how ESG reports are often structured and the kinds of information that airports may choose to feature and include, which lends insight into their perceptions of importance. While it is useful to consider general information about airport ESG reports, it is also helpful to look in greater detail at airport ESG reports published by large US airports; this is provided in the next section which features two case studies for ESG reports for SLC and DFW.

There are a number of limitations related to current practices for ESG reporting for US airports. The information provided in sustainability reports and ESG reports provides valuable insight into the activities and priorities for an airport. There are limitations, however, to the current reporting framework. Since there is not a standard framework for reporting, airports may selectively include and exclude information, and in many cases, airports may consider ESG and sustainability reporting to be more of a marketing opportunity than an objective assessment report. In this context, airport ESG reports may not be fully representative of the airport’s actual sustainability performance.

Some of the limitations of current airport ESG reporting reflect the fact that each airport tailors their ESG report to their specific circumstance. While this flexible and adaptable reporting framework creates challenges when comparing one airport to another, it also may be necessary given the enormous breadth of circumstances at US airports. A common saying in the airport industry is, “if you have seen one airport, you have seen one airport”. This statement reflects the fact that every airport has unique characteristics that affect its operations, ranging from physical infrastructure (e.g., airfield layout and terminal characteristics), environment (urban, suburban or rural), operations (e.g., commercial passenger service, cargo service, international and/or domestic), and ownership (e.g., city owned, airport authority, port authority). Given this diversity, a one size fits all approach to ESG and sustainability may not be effective or desirable.

5.1. Case Studies of Large Hub Airport ESG Reports

This section presents descriptive case studies for ESG reporting for two airports, Salt Lake City (SLC) International Airport and Dallas–Fort Worth (DFW) International Airport. Descriptive case studies are provided to give a broad overview for the use of ESG reports by US airports. This is appropriate given the relative immaturity of ESG reporting by US airports. SLC serves as a hub for Delta Airlines and is also a NPIAS large hub airport about four miles northwest of the city. SLC published their first ESG report in 2021 (providing information about activities in 2020) [85] and published a second ESG report in 2023 (providing information about activities in 2021 and 2022) [67]. After this analysis was complete, a subsequent ESG report was published [86]; the latest revision is very similar to the report analyzed, with more details about specific initiatives and more detailed data analytics about employee demographics, economic performance, and environmental impact.

The second case study is DFW. DFW serves as the largest hub for American Airlines and is also a NPIAS large hub airport. DFW was the first carbon neutral airport in the US and the first US airport to publish an ESG report (in 2016) and has published an ESG report every year since, with the most recent one covering the year 2023 [66]. All of the DFW ESG reports are available online [87].

These two airports were selected because they both explicitly reference SDGs in their ESG report. They also represent the range of airports that have adopted ESG reporting in the US. DFW is one of the largest and busiest airports in the country (second largest in terms of passenger enplanements) and has historically been one of the most environmentally focused US airports. It is the largest carbon neutral airport in the world and is at the highest-level 4+ Transformation for ACI’s Airport Carbon Accreditation [88]. SLC is also an international airport, albeit a smaller one, with about one-third of the passenger enplanements that DFW serves. SLC is also active in the ACI’s Airport Carbon Accreditation program and is currently at a Level 3 Optimization [29] (note that the ACA program shifted from a six level to a seven-level program, and some of the terms have changed slightly). Administratively, the two airports reflect a contrast as well. DFW is owned by a multijurisdictional airport authority that represents both Dallas and Fort Worth and SLC is owned by Salt Lake City through a corporation. DFW opened in 1973, covers more than 26.9 square miles (17,000 acres) [88], and serves civilian aviation activities. SLC opened in 1911, covers about 11.7 square miles (7500 acres), and is a joint use airport, serving civilian aviation activities as well as the Utah Air National Guard, which operates on the east side of the airport (SLC, 2024) [89].

5.1.1. Case Study: Salt Lake City (SLC) ESG Report

The SLC International Environmental Social Governance Report [67] reflects the strategy to consider issues that may impact the airport as well as areas that the airport can impact (the impact of the organization on the economy, environment and people is the framework for impact as defined by GRI, although GRI is not referenced in this report). The original ESG report was published with support by C&S Companies and was approached with a reference to EONS; the subsequent reports frame sustainability in terms of the 2015 UNSDG targets, and address 12 of the 17 SDGs. SLC has a strong focus on sustainability, and the SLC ESG report builds on previous activities, such as participation in the ACA program and LEED certification. A summary of the report information is shown in

Table 9. Salt Lake City Airport SLC ESG report.

Pillar	Issue	Example Airport Information	Related SDGs
Governance Structure and Oversight Systems, processes, and practices to ensure effective, ethical, and transparent management	Airport Structure	SLC Department of Airports (SLCDA) is a department of the city and works closely with other city departments including the Office of Sustainability	5 Gender Equality 8 Decent Work and Economic Growth 9 Industry, Innovation, and Infrastructure
	Airport Advisory Board	9 voting members appointed by the mayor to serve a four-year term
	Risks	Data Management and Cybersecurity CIO and IT protect the airport and customers from cyber threats. Plan to hire a cybersecurity specialist Orientation includes safe cyber practices Emergency Management Work with TSA to strategize on future response AOC (Airport Operations Center) for daily operations; decentralized for enhanced resilience Updating Continuity of Operations Plan since 2022	9 Industry, Innovation, and Infrastructure 12 Responsible Consumption
	Economic Performance	Annual data from 2017 through 2022 Employment: 43,148 FT jobs, USD 2.1 B in wages and income Contributes USD 3.4 B to Utah GDP 325,000 operations and 12.9 M enplanements Airport revenue: USD 398.7 M	8 Decent Work and Economic Growth 10 Reduced Inequalities
	Innovation, Infrastructure, and Facilities	New SLC terminal and concourses features: Seismic and geotechnical resilience Minimize emissions and resource use Unique aesthetic to reflect regional landscape Aligns with LEED Gold standards Energy tracking	9 Industry, Innovation, and Infrastructure 12 Responsible Consumption 13 Climate Action
Social Contribute to well-being of society by supporting employees, customers, and the local community	Employee Background and Safety	Airport employment data 14,271 employees (including tenants) 519 FT airport employees, 7 PT airport employees Construction employment data 259 unionized construction employees work 919,000 h 9 workers comp days 3.7% lost time injury rate Ramp Safety Enforcement Program	3 Good Health and Well Being 5 Gender Equality 8 Decent Work and Economic Growth
Social Contribute to well-being of society by supporting employees, customers, and the local community	Employee Health and Wellness	38.8% participate in health and wellness Wellness Committee of 22 employees meets monthly Benefits include mental health, fitness memberships, and vaccine clinics Activities include 5 blood drives	3 Good Health and Well Being 4 Quality Education 8 Decent Work and Economic Growth
	Employee Education	SLC Employee University Tuition reimbursement, financial counseling Personal loan program and annual financial fair
	Employee Training	Average employee training hours: 22 per year OSHA safety training and SMS training Triennial diversity training, harassment training, and supervisor boot camp
	Diversity, Equity and Inclusion (DEI)	Programs include apprentice, language access, and human rights. Construction data: Local contractors: 80.2% (27 trades, USD 357 M) Union: 51.6% (14 trades, USD 230 M) Merit shop: 48.4% (21 trades, USD 215 M)	5 Gender Equality 10 Reduced Inequalities
	DBE Participation	Employee demographics 18% women, 82% men 1 represent 145 countries About 86% are white, 16% persons of color Doubled women in senior airport management Dedicated Workplace Equity Manager for City and FT HR Business Partner for the airport DEI considerations in recruiting Programs: Accessibility Inclusivity and Human Rights Commission Airport DEI and employee appreciation events Confirmation of pay equity in 2022 DBE spending on construction: about 11%	5 Gender Equality 10 Reduced Inequalities
	Engagement and Outreach	Community engagement Girls in Aviation, Young Eagles, Tours to local groups Workshop series for Small Disadvantaged Business Utilization Noise PublicVue flight tracking system	11 Sustainable Cities and Communities
	Economic Impact	Economic Impact Report (every 5 years) on website Annual financial reports	10 Reduced Inequalities
	User Experience	Accessibility Artificial Intelligence Remote Assistant (AIRA) for blind and low-vision passengers. Hidden Disabilities Sunflower program Sensory rooms planned for New SLC program Family restrooms and nursing mother rooms ADA Compliance Work with concessionaires to support accessibility Consultants hired to identify non-compliance and problem areas Annual ADA/Section 504 training for concessionaires and monthly meetings Feedback form on website for wheelchair service Human Trafficking Blue Lightning Initiative (BLI) in conjunction with DHS and US DOT (training and restroom signs) ACI ASQ Rankings overall satisfaction: 4.17	10 Reduced Inequalities
Environment Consume natural resources at a sustainable rate and limit damaging activities	Greenhouse Gas Emissions (GHG) Reduce Emissions and Use Renewable Energy	Energy Efficiency and Energy Usage Daylighting analysis Stepped roof system installed LED: 100% runway lights, 20% taxiway lights SkySpark Analytics software: real-time data Reduced use of electric heater 1800 h/mo Energy Usage 7% electricity from renewable sources including 100% solar (from roof panels) at Fire Station 11 Local solar partner to provide 50% of SLC electricity for next 25 years GHG emissions in metric tons include 10,000 Scope 1 and 23,000 Scope 2; Scope 3 are 98% of emissions Certifications include Level 3 ACA and LEED Gold Idling and taxiing time New SLC airfield to reduce 15,000 metric tons GHG EV charging and eGSE 164 charging stations including 123 public stations 339 eGSE and 536 airside charging stations SLC policy requires all eGSE by Fall 2023	7 Affordable and Clean Energy 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 13 Climate Action
	Water Minimize Water Usage and Use Water-saving Technologies	Water Conservation and Efficiency Low flow and sensor-based water fixtures installed for 40% reduction in water use Drought-tolerant landscaping (drip-irrigation) HydroPoint Weather Trak system for landscaping monitors leaks in real time to reduce water loss Rental Car Quick Turnaround (QTA) recycles and reuses 80% of the water used Stormwater protection Recycle deicing fluid for four centralized de-ice pads (129,000 gal glycol recovered in 2022) Future water reduction planning Plan to create Water Conservation Action Plan with low flow fixtures in support buildings	6 Clean Water and Sanitation 13 Climate Action 15 Life on Land
	Waste	Solid waste management Updated Recycling, Reuse and Waste Reduction Plan and 2021: Long-term agreement with recycling processor Terminal and concourses 120 recycling locations, 56 water bottle refill stations Construction waste management Tracking waste diverted from landfill 90% diverted including 474,000 tons concrete and 31,000 tons asphalt reused on-site, and 35,000 tons taken offsite for recycling Following LEED Gold standards	11 Sustainable Cities and Communities 12 Responsible Consumption and Production 13 Climate Action
	Climate Risks and Biodiversity	Climate risk and resilience Airport emission reduction support local efforts: Climate Positive 2040 city resolution for clean, renewable energy Climate Adaptation Plan for Public Health Future: Airport to develop a Net Zero Plan and Electrification Master Plan Resilient to seismic threats (withstood 5.7 magnitude earthquake in 2020) Biodiversity supported by Earth Day and Wildlife Management and Wetlands	13 Climate Action 15 Life on Land
Environment	Climate Risks and Biodiversity	465 acres of wetland mitigation added in 2021 and 2022, now over 1000 acres of wetland in wetland mitigation area created in 1995

¹ Based on information in the Data Analytics table on page 26. In the DEI section, it states that 29% of the employees are women. Source: [67].

.

The report references specific SDGs for the sections on Governance Structure and Oversight and Social and Environment, and broadly links these SDGs with the information presented which often includes data. Some information is repeated, which may reflect that many topics may overlap with multiple areas.

Governance Structure and Oversight provides information about the airport board and acknowledges risks related to data management and cybersecurity, which are primarily addressed by the in-house IT department and emergency management, which is addressed by airport staff through strategies introduced by the TSA. The governance section also discusses the economic performance of the airport, providing annual data since 2017 [67].

The social information includes information about employees and employee-related topics, such as safety, training, diversity and inclusion (DEI) and disadvantaged business enterprise (DBE) participation, economic impact, and user experience. In the DEI discussion, employee demographics are presented based on four groups of employees: senior management, new hires, airport police, and airport fire, HR, and attorneys. Grouping airport fire personnel with HR and attorneys seems unusual since attorneys, HR, and fire fighters do not have similar educational requirements or similar duties; this reflects one area where standard employee groups may be useful. Similarly, grouping general employee appreciation events with targeted DBE activities makes it more difficult to discern the context for activities [67]. Little information and no data are provided for economic impact in the section about social considerations, although there are references to provide information where relevant data can be found, and some economic impact data is provided in the Economic Performance section under Governance Structure and Oversight.

The Environment section discusses GHG emissions, water, waste, and climate diversity [67]. The GHG information reflects the ACA program and reports emissions based on ACI’s Scope 1, 2, and 3 definitions [21].

• Scope 1: airport owned facilities and airport owned vehicles, about 0.6% of total emissions;
• Scope 2: purchased energy and purchased heating and cooling, about 1.4% of total emissions;
• Scope 3: aircraft emissions, tenant emissions, passenger vehicles, waste disposal and processing, about 98% of total emissions.

Scope 1 emissions reflect emissions the airport has the most control over and are the smallest component of GHG; Scope 3 emissions are by far the greatest component, reflecting 98% of all emissions, and reflect emissions that the airport may have less direct control over.

SLC is making progress toward environmental goals with reduced Scope 1 and 2 emissions, reduced water use, and programs for recycling waste. Given its proximity to three fault lines, SLC planning and design integrates seismic resilience, and the airport withstood a 5.7 magnitude earthquake in 2020.

5.1.2. Case Study: Dallas Fort Worth (DFW) ESG Report

DFW has published an ESG report every year since 2016 [90]. The reports have referenced the UN SDGs since 2017 [91], and the report has generally increased in length (about 30 pages in 2016 and about 70 pages in 2023), and transitioned away from the explicit reporting based on the GRI Index. The format has varied somewhat over the years, with the 2018 [92], 2019 [93], and 2020 [94] reports including an index that cross-referenced information to the GRI Index. The 2019 report was “informed by Global Reporting Initiative (GRI) standards but may not be inclusive of all GRI indices” (page 7) [93]. The 2020 [94] and 2021 [95] reports were “prepared in accordance with the Global Reporting Initiative (GRI) Global Sustainability Reporting Standards, specifically the core reporting option” (page 2). The 2022 report was prepared “with input from the Global Reporting Initiative (GRI) and Sustainability Accounting Standards Board (SASB) Standards” (Page 2) and reflects the formation of a DFW ESG Council comprised of five DFW executives, including the CFO and General Counsel [96]. The 2023 ESG report has a similar framework to the 2022 report and includes the acknowledgement that the report “was evaluated from a financial materiality standpoint given the increased significance of the ESG information by the financial community” (page 2) [66]. A summary of the report information is shown in

Table 10. DFW ESG report.

Pillar	Issue	Example Airport Information	Related SDGs
Environment Consume natural resources at a sustainable rate and limit damaging activities Environment Consume natural resources at a sustainable rate and limit damaging activities	Climate Action	Key Initiatives. Committed to net zero carbon emissions for Scope 1 and 2 by 2030 Scope 1: 32,678 metric tons CO2 Scope 2: 101,645 metric tons CO2 Scope 3: 9881,420 metric tons CO2 81% reduction in CO2 emissions since 2010 baseline Transitioning to renewable energy for terminal heating. 100% of electricity purchased from renewable sources Zero emission vehicle footprint for DFW’s fleet of over 1000 vehicles Climate Risk. “Storm Ready” designation by NWS and monthly training sessions for severe weather preparedness	Climate Action 7 Affordable and Clean Energy 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 13 Climate Action
	Energy Performance	Work with NREL (National Renewable Energy Lab) on predictive modeling to assess impact of new technologies. In 2021, DFW began using a digital twin model of facilities for energy predictions Numerous projects identified that support goals such as parking garage LED light retrofit, sustainable roof systems Continuous Commissioning system at Terminal B has lowered energy needs since 2007 (partner with Texas A&M Energy Systems Lab) 69% of energy from renewable sources	Energy Performance 7 Affordable and Clean Energy 11 Sustainable Cities and Communities 12 Responsible Consumption and Production 13 Climate Action
	Zero Waste and Circular Economy	Aspirational goal for zero waste in the next 20 years means at least 90% of waste will be diverted from landfills, incinerators, and the environment 94% construction waste diverted from landfills In-house recycling program for mixed materials (e.g., paper, plastic, cardboard, and metal) and partnership with Dell Computer for electronic waste Food waste is composted, and used cooking oil is converted into SAF. Over 30,000 lbs of used cooking oil collected each month 15.9% municipal solid waste is diverted from landfills through recycling (6600+ tons)	Circular Economy 9 Industry, Innovation, and Infrastructure 12 Responsible Consumption and Production 13 Climate Action
	Water and Biodiversity	Water conservation has saved 226 M gal water through use of water from non-potable sources in partnership with the City of Fort Worth Watershed monitoring program ensures healthy streams through regular data collection and assessment of macroinvertebrates Glycol is captured and stored, sent to a treatment plant, and then released via controlled discharge into the Trinity River Authority Water use includes 90.2 M gallons surface water, 179.1 M gallons reclaimed water, and 1.3 B gallons potable water	Water and Biodiversity 6 Clean Water and Sanitation 12 Responsible Consumption and Production 14 Life Below Water 15 Life on Land
Social Contribute to well-being of society by supporting employees, customers and the local community	Employees	2008 employees 66.1% male, 33.9% female, 54% people of color Average age 45.5, turnover rate 16.5% 25% participate in resource groups 99% completed job specific training Reportable incident rate 7.11, zero fatalities 31 injuries resulted in lost time days Programs include Risk Council (meets quarterly, process to identify and mitigate risks) and Safety Forum (two-day event for airfield and employee safety) 90% participate in wellness program DFW named Healthiest Employer in Texas and received Gold level recognition from the American Heart Association	Health, Safety and Wellness 3 Good Health and Well-Being, 4 Quality Education, 11 Sustainable Cities and Communities 17 Partnership to achieve SDGs Equity 4 Quality Education 5 Gender Equality 8 Decent Work and Economic Growth 10 Reduced Inequalities 16 Peace, Justice, and Strong Institutions 17 Partnership to achieve SDGs
	Community	Community engagement involves education and communication. Engagement and advocacy reflecting FAA’s PBN Blueprint for Engagement Volunteer work. 160 employees logged 2857 h to benefit 150 community organizations DFW is involved in 80 community events and hosted 24 school groups and community organizations. DFW contributed USD 3.3 B in gross product and created 39,425 jobs (annual) between 2016 and 2020. Noise Management includes noise monitoring and complaint monitoring through online complaint buttons (2570 complaints) and email, phone and voicemail (143 complaints). Customer experience is positive; overall customer satisfaction 4.11 in 2022.
Social Contribute to well-being of society by supporting employees, customers and the local community		Customer experience initiatives include autonomous charging for vehicles, new wireless, and express stores that do not require check-out 40% of expenditures through MBE and WBEas well as strong participation by DBE (26% of spend) and ACDBE (airport concessions, 46% of total revenue) with goals exceeded every year DFW has a number of programs to support M/WBE through business development and to recognize and encourage supplier diversity	Wellness 3 Good Health and Well-Being, 4 Quality Education, 11 Sustainable Cities and Communities 17 Partnership to achieve SDGs Equity 4 Quality Education 5 Gender Equality 8 Decent Work and Economic Growth 10 Reduced Inequalities 16 Peace, Justice, and Strong Institutions, 17 Partnership to achieve SDGs
	Safety and Security	7141 service calls for the fire with average response times of 5:30 for structural fires, 6:50 for medical calls, and 3:04 for ARFF units Law enforcement completed ABLE training to encourage peer bystander support and intervention DFW Airport Fire Training and Research Center has supported adoption of fluorine-free foams (F3)
Governance Systems, processes, and practices to ensure effective, ethical, and transparent management	Governance Structure	Laws and Regulations: airport cannot make a profit on airline charges; non-airline profits must be retained and used at the airport Ethics and Compliance: ethics hotline 24/7 by third-party; annual ethics training for all employees and leaders must submit annual ethics certification Board of Directors and Board Diversity: 11 voting members include mayors and representatives appointed by the city councils of Dallas and Fort Worth; 75% people of color and 33% women Strategy: Councils (aka working groups) address critical elements of the strategic plan Financial Management includes 10-year financial plan and annual reports for revenues (USD 12.77/enplanement, non-airline net revenue USD 148 M includes USD 122 M DFW capital account and USD 126 B airfield transfer. Actual was −1.5% of budget in FY23. 78% of capital projects funded through debt in the last five years	No SDGs identified
	Risk Management	Financial risk management: cash on hand to fund 20 months of operations Capital program risk management: USD 9 B of assets and USD 9.2 B capital program through FY29 Cybersecurity managed by in house personnel and contract with third party for detection and response Reliance on key partners including American Airlines, FAA, TSA and CBP
	Reporting, Transparency and Assurance	Complies with Municipal Securities Rulemaking Board Investor website: https://www.dfwairport.com/business/about/investors accessed 13 May 2025.

Source: [66].

.

The chapters on the Environment, Social, and Governance include facts interspersed with example initiatives, partnerships, and graphs to illustrate trends. Trends may be considered over different periods, depending on the topic; for example, FY10 to FY23 for Scope 1 and 2 emissions; FY20 to FY23 for construction waste; 1995 to 2023 for noise complaints. Reflecting the financial materiality considerations, the report includes statements, such as the following in the Environment chapter.

• “No financially material instances of environmental non-compliance occurred in FY 2023” (page 16), in the introduction to the Environment chapter.
• “Potential temporary closures of the Airport do not have a financially material impact on DFW’s ability to repay its bonds due to the cost recovery nature of U.S. airports as promulgated by the Federal Aviation Administration (FAA) and as contractually agreed upon by the signatory airlines as part of the Airport’s Use and Lease Agreements” (page 20). This statement is in the Climate Risk section of the Environment chapter.

6. Discussion

The DFW ESG is similar to the SLC ESG report in that both reference the UN SDG goals, both present topics with supporting data, initiatives, and examples. Both reports discuss emissions in the context of Scope 1, 2, and 3 emissions and reference participation in the ACI ACA program. The DFW report may provide more discussion of goals for the future and discuss activities in the context of initiatives that started a number of years ago; this may reflect the fact that the most recent ESG report is the latest in a series of ESG reports spanning eight years. For example, in the Zero Waste and Circular Economy, the DFW ESG report provides a discussion of recycling that references the cooking oil to SAF initiative that began in 2019 and the food waste composting program that began in 2021. The DFW report also discusses many activities in the context of their partner organizations, such as the US Department of Energy National Renewable Energy Lab (DOE NREL) as a partner for zero-emission vehicle blueprint, the Texas A&M Energy Systems Laboratory for Continuous Commissioning for Green Buildings, and Dell Computer Corporation for electronic waste recycling [66]. All these partnerships reflect DFW’s strong focus on the environment, as evidenced by their early adoption of ACI’s ACA Program and more recent capital project initiatives.

The DFW ESG report does not reference SDGs for the Governance chapter and includes more information for risk management, mentioning their use of enterprise risk management (ERM), a systematic approach to addressing organizational risk through identification, assessment, and mitigation. The DFW report also provides a brief discussion on some prominent risks, acknowledging financial risk, capital risk, human capital risk, natural disaster risk, cybersecurity risk, and the risks associated with reliance on key partners [66].

The SLC report identifies SDGs specifically for each issue (e.g., the issue of Water within the Environment section) [67] whereas the DFW report identifies SDGs for six “Sustainability North Stars” that are the focus areas for DFW’s Sustainability Management Plan [66]. The topic areas of climate action, energy performance, circular economy, and water and biodiversity are addressed in the Environment chapter. For DFW, the topic areas equity and health and safety and wellness are addressed in the Social chapter. A detailed comparison of the SDGs for SLC and DFW as well as for the ACI Best Practices and the WEF is provided in Table 11. These were the only two airports that included specific references to SDGs in the ESG report; although previous versions of the ATL ESG + P report included SDGs [97], the most recent version did not [63].

All of the reporting frameworks shown in Table 11 address the majority of the SDGs. The WEF anchors their reporting with the People, Prosperity, Planet, and Governance framework that aligns verbatim with the UN framework and address all SDGs except 2 No Hunger and 11 Sustainable Cities and Communities [55]. Neither the SLC or DFW ESG plan addresses SDG 1 No Poverty or SDG 2 No Hunger. ACI includes SDG 1 as economic and social and 2 as social components (the 2021 ATL ESG + P report [97] included both of these SDGs, although this information is not shown in the table). The inclusion or exclusion of SDGs 1 and 2 reflects different perspectives regarding the breadth of the social component and whether the umbrella of the social pillar expands to include poverty and hunger in the larger community served by the airport.

ACI addresses 16 of the 17 SDGs, omitting SDG 17 Partnerships; SLC also does not address SDG 17 [22]. DFW addresses partnerships under the social pillar [66], whereas WEF addresses it under the governance issue [55]. SLC is the only entity that does not include SDG 16 Peace, Justice, and Strong Institutions, which is addressed as a social (DFW and ACI), economic (ACI), and governance (WEF) issue [22,55,66,67]. SDGs are open to interpretation and may be framed under different contexts without a standard format.

Table 11. Comparison of Sustainable Development Goals to associated pillars for WEF, ACI, and SLC.

SDG	Description	WEF [55]	ACI [22]	SLC ESG [67]	DFW ESG [66]
1	No Poverty	People Prosperity	Economic Social
2	No Hunger		Social
3	Good Health and Well Being	People	Economic Social Environmental	Social, Employee Safety Social, Employee Health and Wellness	Social
4	Quality Education	People	Social	Social, Employee Health and Wellness	Social
5	Gender Equality	People	Social	Governance, Airport Structure Social, Employee Safety Social, DEI Social, DBE	Social
6	Clean Water and Sanitation	Planet	Environmental	Environment, Water	Environment
7	Affordable and Clean Energy	Planet	Environmental	Environment, GHG Emissions	Environment
8	Decent Work and Economic Growth	Prosperity	Economic Social	Governance, Airport Structure Governance, Economic Performance Social, Employee Safety Social, Employee Health and Wellness	Social
9	Industry, Innovation, and Infrastructure	Prosperity	Economic Social	Governance, Airport Structure Governance, Risks Governance, Innovation, and Infrastructure	Environment
10	Reduced Inequalities	People Prosperity	Social	Governance, Economic Performance Social, DEI Social, DBE Social, Economic Impact Social, User Experience	Social
11	Sustainable Cities and Communities		Economic Social Environmental	Social, Outreach Environment, GHG Emissions Environment, Waste	Environment Social
12	Responsible Consumption and Production	Governance Planet	Economic Environmental	Governance, Risks Governance, Innovation, and Infrastructure Environment, GHG Emissions Environment, Waste	Environment
13	Climate Action	Planet	Environmental	Governance, Innovation, and Infrastructure Environment, GHG Emissions Environment, Water Environment, Waste Environment, Climate Risk and Biodiversity	Environment
14	Life below Water	Planet	Environmental		Environment
15	Life on Land	Planet	Environmental	Environment, Water Environment, Climate Risk and Biodiversity	Environment
16	Peace, Justice, and Strong Institutions	Governance	Economic Social		Social
17	Partnerships for the Goals	Governance			Social

Sources: [22,55,65,66].

Table 11. Comparison of Sustainable Development Goals to associated pillars for WEF, ACI, and SLC.

SDG	Description	WEF [55]	ACI [22]	SLC ESG [67]	DFW ESG [66]
1	No Poverty	People Prosperity	Economic Social
2	No Hunger		Social
3	Good Health and Well Being	People	Economic Social Environmental	Social, Employee Safety Social, Employee Health and Wellness	Social
4	Quality Education	People	Social	Social, Employee Health and Wellness	Social
5	Gender Equality	People	Social	Governance, Airport Structure Social, Employee Safety Social, DEI Social, DBE	Social
6	Clean Water and Sanitation	Planet	Environmental	Environment, Water	Environment
7	Affordable and Clean Energy	Planet	Environmental	Environment, GHG Emissions	Environment
8	Decent Work and Economic Growth	Prosperity	Economic Social	Governance, Airport Structure Governance, Economic Performance Social, Employee Safety Social, Employee Health and Wellness	Social
9	Industry, Innovation, and Infrastructure	Prosperity	Economic Social	Governance, Airport Structure Governance, Risks Governance, Innovation, and Infrastructure	Environment
10	Reduced Inequalities	People Prosperity	Social	Governance, Economic Performance Social, DEI Social, DBE Social, Economic Impact Social, User Experience	Social
11	Sustainable Cities and Communities		Economic Social Environmental	Social, Outreach Environment, GHG Emissions Environment, Waste	Environment Social
12	Responsible Consumption and Production	Governance Planet	Economic Environmental	Governance, Risks Governance, Innovation, and Infrastructure Environment, GHG Emissions Environment, Waste	Environment
13	Climate Action	Planet	Environmental	Governance, Innovation, and Infrastructure Environment, GHG Emissions Environment, Water Environment, Waste Environment, Climate Risk and Biodiversity	Environment
14	Life below Water	Planet	Environmental		Environment
15	Life on Land	Planet	Environmental	Environment, Water Environment, Climate Risk and Biodiversity	Environment
16	Peace, Justice, and Strong Institutions	Governance	Economic Social		Social
17	Partnerships for the Goals	Governance			Social

Sources: [22,55,65,66].

For example, SDG 8 Decent Work and Economic Growth is considered prosperity by WEF [55], economic and social by ACI [22], social and governance by SLC [67], and social by DFW [66]. Overall, SLT provides a much more detailed connection between their SDGs and specific issues, whereas DFW provides much broader categories and does not designate any SDGs related to governance.

The examination of airport SDGs in airport ESG reports reflects larger trends: the diversity of reporting approaches, a lack of standard information, even if the same information is included, it may be categorized under different pillars, and often the information provided is not closely mapped to a standard reporting framework.

Without this standardization, it is much harder to assess an airport’s sustainability in the context of comparison with their historic activities, their goals for the future, and their airport peers. Utilization of standard reporting formats, standard tables and standard data would go a long way toward supporting the provision of useful information that can be benchmarked and interpreted in the context of other activities. A standard reporting framework could still be tailored to individual airports, and it would be possible for airports to feature the information for sections that are relevant and important to their airport and omit sections that are not relevant.

In 2024, ACI-North America (ACI-NA) identified 20 disclosure elements that are recommended for inclusion in an airport ESG report, as shown with descriptions for each element in Table 12. These 20 elements include 9 elements addressing environmental components, 4 elements addressing social components, and 7 elements addressing governance. Of these 20 elements, 7 can be addressed with a narrative discussion in the ESG report, and the remaining 13 of these elements should be addressed with data. The narrative elements include waste and water management in environmental, and governance topics include organizational structure, risk management, cybersecurity, transparency, and ethics and compliance.

The SLC and DFW reports were qualitatively assessed with respect to each of these 20 elements, and each item was given a score between 0 (did not address) and 3 (completely addresses) to reflect the information provided. The score was assessed using the following framework:

0

Elements were not included;

1

Element was briefly mentioned;

2

Element was addressed with a metric for quantitative topics (addressed with some detail for narrative item);

3

Element was addressed with a metric and data for a period of time for quantitative topics (addressed with significant details for narrative item).

The results of this analysis for SLC and DFW are shown in

Table 13. Quantitative assessment of recommended disclosure elements in ESG reports.

	SLC	DFW
Environmental
Energy consumption	2	2
2 Energy intensity	2	3
3 Greenhouse gas emissions (GHG) Scope 1 and 2	3	3
4 GHG intensity—Scope 1 and 2	2	3
5 Climate risk exposure and adaptation *	3	3
6 Environmental commitments and progress	2	3
7 Environmental non-compliance	0	3
8 Waste management *	3	3
9 Water management *	3	3
Social
10 Diversity, equity, and inclusion (DEI)—workforce ethnicity and gender	3	3
11 Business supplier diversity (DBE/MWBE)	2	3
12 Concessionaire diversity (ACDBE)	2	3
13 Workplace/employee safety	2	3
Governance
14 Governance/organizational structure *	0	3
15 Board of directors’ background/ diversity	1	2
16 Executive management background/diversity	1	2
17 Approach to risk management *	2	3
18 Cybersecurity—general discussion *	3	3
19 Reporting and transparency *	1	3
20 Ethics and compliance *	0	1
Total (max score 60)	37	55

* Narrative.

. SLC had a total of 37, and DFW had a total of 55 (out of a possible score of 60); a higher score reflects more alignment between the items in the ESG report and the elements recommended for inclusion per the ACI-NA. DFW’s higher score reflects greater congruence with ACI recommendations and may also reflect a greater maturity in ESG reporting (since DFW was the first airport in the US to publish an ESG report) and a long-standing focus on sustainability (DFW was the first carbon neutral airport in the US) and may be affected by its governance structure, which is more analogous to an independent airport authority rather than a municipal airport that functions within a city or county government. SLC would have a higher score if they had included an environmental non-compliance statement and information about their organizational structure and ethics and compliance policies. The environmental compliance statement may simply be a statement regarding whether there were any spills or fines or other financially material instances of environmental non-compliance.

Table 12. Disclosure elements recommended for inclusion in ESG reports by ACI-NA.

	Description
Environmental
Energy consumption	Total energy consumption.
2 Energy intensity	Ratio of energy consumption and organization-specific metric (consistent metric over time).
3 Greenhouse gas emissions (GHG) Scope 1 and 2	Scope 1 GHG emissions and Scope 2 GHG emissions (market-based and location-based).
4 GHG intensity—Scope 1 and 2	Ratio of GHG emissions and organization-specific metric.
5 Climate risk exposure and adaptation *	Climate change risk exposure analysis and strategies to mitigate risks if financially material.
6 Environmental commitments and progress	Formally announced environmental plans, strategies, and/or targets. May include but not limited to greenhouse gases, zero waste, etc. Track and report progress.
7 Environmental non-compliance	Instances of non-compliance with environmental laws and regulations including spills and pollution if financially material.
8 Waste management *	Activities leading to waste generation and initiatives to address these impacts.
9 Water management *	Activities impacting both water quality and water use and strategy to manage impacts.
Social
10 Diversity, equity, and inclusion (DEI)—workforce ethnicity and gender	Airport workforce diversity and DE&I practices (e.g., staff training, hiring practices, minorities in leadership, etc.). Airport workforce diversity and DE&I practices for recruiting.
11 Business supplier diversity (DBE/MWBE)	Airport business diversity practices (e.g., DBE, MWBE, on-the-job training programs, networking events, etc.).
12 Concessionaire diversity (ACDBE)	Airport’s business diversity practices (ACDBE, on-the-job training programs, networking events, etc.).
13 Workplace/employee safety	Airport workplace safety practices, including the Safety Management System (SMS) and any accreditations and certificates earned.
Governance
14 Governance/organizational structure *	Legal structure (organization’s enabling act or other statutory authority), use agreement, regulatory requirements.
15 Board of directors’ background/diversity	List board members, appointment process, Board committee structures, frequency of meetings, Board responsibilities / approvals, ethnic diversity, types of business experience, financial management, and controls policies approved by Board (could be included in Social with DEI information).
16 Executive management background/diversity	List executive management name and position, diversity, and years of experience.
17 Approach to risk management *	Airport approach to risk management, including enterprise risk management (ERM), if applicable. Discuss major risks and how the airport is mitigating those risks, including ESG risks.
18 Cybersecurity—general discussion *	Describe airport’s approach to cybersecurity. Include discussion of phishing testing, penetration testing, tabletop exercises, insurance (not stating amount), and outside assistance to monitor network. Discuss if airport is complying with Payment Card Industry (PCI) security standards and if it stores any customer credit card information.
19 Reporting and transparency *	Describe investor disclosure practices, timeliness, and accuracy of reporting to Board, transparency of information, including State and Local open records processes.
20 Ethics and compliance *	Describe ethics practices, hotlines, Foreign Corrupt Practices Act compliance, regulatory requirements (if applicable), and training.

* Narrative only. Source: Disclosure Elements: [59]; Descriptions adapted from [59,86].

Table 12. Disclosure elements recommended for inclusion in ESG reports by ACI-NA.

	Description
Environmental
Energy consumption	Total energy consumption.
2 Energy intensity	Ratio of energy consumption and organization-specific metric (consistent metric over time).
3 Greenhouse gas emissions (GHG) Scope 1 and 2	Scope 1 GHG emissions and Scope 2 GHG emissions (market-based and location-based).
4 GHG intensity—Scope 1 and 2	Ratio of GHG emissions and organization-specific metric.
5 Climate risk exposure and adaptation *	Climate change risk exposure analysis and strategies to mitigate risks if financially material.
6 Environmental commitments and progress	Formally announced environmental plans, strategies, and/or targets. May include but not limited to greenhouse gases, zero waste, etc. Track and report progress.
7 Environmental non-compliance	Instances of non-compliance with environmental laws and regulations including spills and pollution if financially material.
8 Waste management *	Activities leading to waste generation and initiatives to address these impacts.
9 Water management *	Activities impacting both water quality and water use and strategy to manage impacts.
Social
10 Diversity, equity, and inclusion (DEI)—workforce ethnicity and gender	Airport workforce diversity and DE&I practices (e.g., staff training, hiring practices, minorities in leadership, etc.). Airport workforce diversity and DE&I practices for recruiting.
11 Business supplier diversity (DBE/MWBE)	Airport business diversity practices (e.g., DBE, MWBE, on-the-job training programs, networking events, etc.).
12 Concessionaire diversity (ACDBE)	Airport’s business diversity practices (ACDBE, on-the-job training programs, networking events, etc.).
13 Workplace/employee safety	Airport workplace safety practices, including the Safety Management System (SMS) and any accreditations and certificates earned.
Governance
14 Governance/organizational structure *	Legal structure (organization’s enabling act or other statutory authority), use agreement, regulatory requirements.
15 Board of directors’ background/diversity	List board members, appointment process, Board committee structures, frequency of meetings, Board responsibilities / approvals, ethnic diversity, types of business experience, financial management, and controls policies approved by Board (could be included in Social with DEI information).
16 Executive management background/diversity	List executive management name and position, diversity, and years of experience.
17 Approach to risk management *	Airport approach to risk management, including enterprise risk management (ERM), if applicable. Discuss major risks and how the airport is mitigating those risks, including ESG risks.
18 Cybersecurity—general discussion *	Describe airport’s approach to cybersecurity. Include discussion of phishing testing, penetration testing, tabletop exercises, insurance (not stating amount), and outside assistance to monitor network. Discuss if airport is complying with Payment Card Industry (PCI) security standards and if it stores any customer credit card information.
19 Reporting and transparency *	Describe investor disclosure practices, timeliness, and accuracy of reporting to Board, transparency of information, including State and Local open records processes.
20 Ethics and compliance *	Describe ethics practices, hotlines, Foreign Corrupt Practices Act compliance, regulatory requirements (if applicable), and training.

* Narrative only. Source: Disclosure Elements: [59]; Descriptions adapted from [59,86].

In both reports, there was significant and meaningful information provided beyond the elements recommended for inclusion. The SLC report discussed that this ESG report utilized input from previous reports that were developed with input from a number of stakeholders, including employees, city representatives, airlines, concessionaires, and rental car companies. This perhaps acknowledges the stakeholder theory for ESG reporting, as put forth by Freeman [98], which suggests that ESG reporting is an opportunity to provide evidence to important stakeholders. The inclusion of these stakeholders may also support the managerial perspective of the stakeholder theory, which suggests inclusion of stakeholders who have a more direct impact on the airport; this may explain why numerous airport stakeholders may have been absent from the process, including local citizens and community members (including voters and airport neighbors), regulatory agencies, investors, passengers, aviation businesses at the airport, and the numerous employees at the airport that are contract employees rather than direct employees of the airport. While the stakeholder theory does have some merit, the legitimacy theory for ESG reporting is more compellingly appropriate. The legitimacy theory suggests that airports may use the ESG report as an opportunity to provide evidence that the organization is fulfilling its duties within appropriate bounds [99]; in most cases, this means the airport is meeting its obligations to provide air mobility for passengers and cargo and support economic development in a context that supports environmental and social expectations with appropriate governance. The legitimacy theory for airport ESG reporting is compelling since airports work to build strong communication and positive public perception, and if there is misalignment with organizational activities and public desires, there may be a legitimacy gap [100] that may have real consequences. The need for an airport to keep the community informed is not merely a good business practice, it is also mandated by the FAA in many cases, such as for FAA-funded airport master planning and noise compatibility programs. Keeping the public informed is such a key component of airport management in the US that it is also one of twelve items included in the Code of Ethics per the American Association of Airport Executives [101]. Airports with a legitimacy gap have also been faced with closure and takeover by other government entities, as evidenced by the Santa Monica Airport (SMO), which will close at the end of 2028, and legislation by the State of Georgia to take over management of Hartsfield–Jackson Atlanta International Airport (ATL) in 2019 (the latter was unsuccessful).

It is also interesting to compare SLC and DFW with airports in other countries where ESG reporting is more established, as shown in Table 14, which provides information about SLC and DFW, as well as Sydney Airport (SYD) in Australia and the Amsterdam Airport Schiphol (AAS) in the Netherlands. Both Sydney and the Royal Schiphol Group have a much more established framework for ESG reporting, and the Royal Schiphol Group is required to provide reporting as part of European Union regulations, and it has the longest report, with 102 pages, included as part of a 301 page annual report. The DFW report is approximately the same length as the SYD report (72 and 74 pages, respectively), and all are significantly longer than the SLC report (42 pages). AAS and SYD both reference more standards and participate in more accreditation programs, with AAS identifying seven accreditations and SYD identifying five standards and initiatives (beyond ACI ACA). Both DFW and SLC reference the ACI-NA framework, and DFW also acknowledges input from GRI. AAS and SYD also address fewer UN SDG goals, with AAS referencing 9 goals and SYD referencing 6 goals, significantly less than SLC’s 12 UN SDG goals and DFW’s 15 SDG goals. DFW actually says their approach advances all 17 SDGs, but their North Star sustainability initiatives address 15 of the SDGs. Both SYD and AAS also have much more clearly mapped connections between the SDGs and the material topics, which are also mapped clearly to key performance indicators (KPIs) and goals.

All airports identify stakeholders and acknowledge that airlines and government entities provided input into the selection of material topics. At SLC, the only government entity acknowledged was the local government, with specific mention of city representatives from other departments. This reflects the fact that SLC is a city-owned airport, and the city is an important stakeholder. DFW included government and mentioned specifically the neighbor cities of DFW since both Dallas and Fort Worth are owners and as such are represented on the DFW Airport Board. Both AAS and SYD recognized government stakeholders, but in neither case were local governments specifically mentioned.

Another notable difference in stakeholders is that both AAS and SYD included financial stakeholders, shareholders, owners, and debt investors, whereas neither DFW nor SLC specifically mentioned financial stakeholders. All airports referenced some kind of business partners, whether concessionaires (DFW and SLC), business partners (AAS), or suppliers (SYD). In some cases, similar stakeholders may have been involved, although they were referenced differently (e.g., DFW acknowledged internal stakeholders but did not specify exactly what this meant; it was interpreted to include employees, although it may be much broader).

AAS not only identifies stakeholders but also provides a detailed description of the matters discussed with each stakeholder group as well as the method for engagement (e.g., regular meetings, financial briefings, collaborative partnerships, feedback surveys). The method of engagement is tailored to the stakeholder and the matters discussed. This provides an excellent framework for stakeholder engagement as well as strong communication.

Table 14. Comparison of DFW and SLC with airports in other countries.

	Royal Schiphol Group Amsterdam Airport Schiphol (AAS)	Sydney Airport (SYD)	Dallas–Fort Worth (DFW)	Salt Lake City (SLC)
UN SDG	9 goals:	6 goals:	15 goals:	12 goals:
Pages in ESG report	102 pages in Sustainability section	74 pages	72 pages	43 pages
ACA Accreditation	ACA Level 5	ACA Level 4+	ACA Level 4+	ACA Level 3
	AAS	SYD	DFW	SLC
Stakeholders Consulted for Key/Material Topics Stakeholders Consulted for Key/Material Topics	Airlines	Business and airline partners	Airlines	Airlines
	Employees	Employees	Internal stakeholders	Employees
	Passengers	Customers	Passengers
	Local residents
	Government bodies	Government stakeholders	Neighbor cities and other third parties	City representatives (from non-airport-related departments)
	Financial stakeholders and shareholders	Owners and debt investors
	Sector partners and business partners and suppliers	Community suppliers	Business partners and owners
			Concessionaires	Concessionaires
	Network and special interest organizations and knowledge institutions	Tourism bodies and industry associations	Utilities	Rental car companies
Referenced standards, documents, and accreditations (other than ACI ACA and UN SDG)	Accreditations Corporate Sustainability Reporting Directive (CSRD) Science Based Targets MSCI Sustainalytics ISO 50001 Ecovadis GSES	With reference to GRI Standards Aligns to relevant SASB Standards TCFD (Task Force on Climate Related Financial Disclosures) UN Global Compact Corporate Responsibility Initiative Business for Societal Impact	Input from GRI Input from ACI-NA ESG Framework published in March 2024	Data mapped to Material topics in ACI-NA ESG Framework published in March 2024
PFAS	Mentioned 36 times; e.g., context soil contamination, historic use of AFFF, risk of construction delays, PFAS testing, PFAS legislation, groundwater contamination, PFAS level, detection, remediation	Mentioned 5 times; e.g., context National Environmental Management Plan, concentration, sources, impacts, risk, referral to more information on PFAS management on website	No mention	Mentioned 1 time: context PFAS conference attended

Notes: Royal Schiphol Group is the owner and operator of Amsterdam Airport Schiphol (AAS), Rotterdam The Hague Airport, and Lelystad Airport and has majority stake in Eindhoven Airport (51%), a stake in Maastricht Aachen Airport (40%), and interest in Brisbane Airport and Hobart Airport. For DFW, Strategy advances all 17 UN SDG goals; DFW focus areas (aka six North Stars) align with 15 goals. Sources: SLC [67], DFW [66], SYD [49], AAS [102].

Table 14. Comparison of DFW and SLC with airports in other countries.

	Royal Schiphol Group Amsterdam Airport Schiphol (AAS)	Sydney Airport (SYD)	Dallas–Fort Worth (DFW)	Salt Lake City (SLC)
UN SDG	9 goals:	6 goals:	15 goals:	12 goals:
Pages in ESG report	102 pages in Sustainability section	74 pages	72 pages	43 pages
ACA Accreditation	ACA Level 5	ACA Level 4+	ACA Level 4+	ACA Level 3
	AAS	SYD	DFW	SLC
Stakeholders Consulted for Key/Material Topics Stakeholders Consulted for Key/Material Topics	Airlines	Business and airline partners	Airlines	Airlines
	Employees	Employees	Internal stakeholders	Employees
	Passengers	Customers	Passengers
	Local residents
	Government bodies	Government stakeholders	Neighbor cities and other third parties	City representatives (from non-airport-related departments)
	Financial stakeholders and shareholders	Owners and debt investors
	Sector partners and business partners and suppliers	Community suppliers	Business partners and owners
			Concessionaires	Concessionaires
	Network and special interest organizations and knowledge institutions	Tourism bodies and industry associations	Utilities	Rental car companies
Referenced standards, documents, and accreditations (other than ACI ACA and UN SDG)	Accreditations Corporate Sustainability Reporting Directive (CSRD) Science Based Targets MSCI Sustainalytics ISO 50001 Ecovadis GSES	With reference to GRI Standards Aligns to relevant SASB Standards TCFD (Task Force on Climate Related Financial Disclosures) UN Global Compact Corporate Responsibility Initiative Business for Societal Impact	Input from GRI Input from ACI-NA ESG Framework published in March 2024	Data mapped to Material topics in ACI-NA ESG Framework published in March 2024
PFAS	Mentioned 36 times; e.g., context soil contamination, historic use of AFFF, risk of construction delays, PFAS testing, PFAS legislation, groundwater contamination, PFAS level, detection, remediation	Mentioned 5 times; e.g., context National Environmental Management Plan, concentration, sources, impacts, risk, referral to more information on PFAS management on website	No mention	Mentioned 1 time: context PFAS conference attended

Notes: Royal Schiphol Group is the owner and operator of Amsterdam Airport Schiphol (AAS), Rotterdam The Hague Airport, and Lelystad Airport and has majority stake in Eindhoven Airport (51%), a stake in Maastricht Aachen Airport (40%), and interest in Brisbane Airport and Hobart Airport. For DFW, Strategy advances all 17 UN SDG goals; DFW focus areas (aka six North Stars) align with 15 goals. Sources: SLC [67], DFW [66], SYD [49], AAS [102].

AAS and SYD also included disclosures about information that was not favorable. For example, SYD acknowledged an increase in total waste (attributable to an increase in passenger traffic) and acknowledged a three year permit to pollute the adjacent Mill Stream, elaborating on pollutants that include “wet wipes, sanitary products and syringes, are also contained in the sewage overflow water discharging into Botany Bay” ([49], page 28). The PFAS information in Table 14 illustrates the difference in willingness to disclose potentially unfavorable information.

PFAS is a “forever chemical” that causes cancer and may be prevalent at airports because it is in aqueous film forming foam (AFFF) which was used at airports for fire fighting for decades due to its effectiveness in containing aircraft fires. All airports worldwide are faced with the issue of managing possible contamination of soil and local water supplies due to PFAS. Notably, both SYD and AAS acknowledge the issue and provide information about exposure, concentration, impact, risk, and management of environmental issues related to PFAS. Strongly contrasting this, DFW does not mention PFAS at all, and SLC only mentions it in the context that someone attended a PFAS conference. This illustrates a large discrepancy in the approach to ESG reporting by some US airports, and provides evidence that ESG reporting by US airports may tend to be more oriented in the direction of positive public relations and marketing, rather than full disclosure that would be of interest for a variety of stakeholders, from local community members and governments to potential investors.

The SLC and DFW ESG reports are useful communication tools, and they provide a lot of substantive information, but they do not provide the level of detail or provide strong connections between the information provided and its context as it relates to airport goals and strategies. This contrasts with the detailed and substantive information that is provided by AAS. This information is clearly mapped to airport goals and strategies and is presented in a context that is useful for investors and other financial stakeholders. AAS provides a double materiality assessment (DMA), which provides an assessment that reflects the financial implications of the airport practices as well as the implications in terms of the actual impact on the environment and society. From a legitimacy theory, the information provided by SLC and DFW reflects the different role and expectations for airports in the US. SLC and DFW are owned by local governments, and there are no regulations for ESG reporting in the US. Perhaps there is less societal interest in social and environmental issues and reporting in the US, as compared to Europe.

In terms of regulatory oversight in the US, the FAA provides regulatory oversight of US airports, is a primary investor in US airport infrastructure through funding provided by the Airport Improvement Program and provides regulatory oversight of funds collected by airports through the Passenger Facility Charge (PFC) program. The FAA has no requirements for ESG reporting, although they do support environmental activities and community programs and require substantial documentation through initiatives, such as the required wildlife management programs, EIS, airport master planning, and noise compatibility planning.

7. Recommendations and Conclusions

On the global stage, sustainability is increasingly in the spotlight, as evidenced by ACI’s project to create standard reporting guidelines for airports and by the SEC’s recent ruling for increased disclosure requirements for public companies in the US. There may continue to be some controversy revolving around sustainability in aviation, as demonstrated by the beginning of flygskam in 2018 and, more recently, the “official” end of flygskam by Swedish government officials, and as changing administrations in different countries change the approach to sustainability and its priority in funding decisions.

US airport ESG reporting is relatively new, and US airports are making good progress as they develop reports to meet the needs of their airport. The lack of reporting standards may present some challenges when it comes to comparing airports; however, this may be addressed in the future as US airports use information published by ACI-NA, such as the 20 elements recommended for inclusion in ESG reports. US airports can benefit from examining the practices of European airports and other airports that have a more mature framework for ESG reporting. Based on the case studies, US airport ESG reports could be strengthened by providing stronger connections between material topics, airport goals and strategies, and performance metrics. US ESG reporting would also benefit from acknowledging challenges, rather than merely focusing on the success stories. US airports would also benefit by scaling back, narrowing their focus to the UN SDGs that make the most sense, and prioritizing activities accordingly (after all, if everything is important, nothing is important).

Airport authorities can support these activities by incorporating appropriate sustainability in their organizational mission and goals and providing funding as appropriate. Communicating the value of these activities and ensuring accountability through regular reporting in a structured format will help institutionalize best practices.

Policy makers can support ESG reporting by providing a standard template, perhaps by adopting the 20 elements recommended by ACI-NA. Each element can have associated example metrics, and the airport can select metrics that are appropriate to their situation. Perhaps an analogy with airport rates and charges is appropriate, and the framework is not prescribed, but it must be transparent and accountable. Policy makers can also support ESG reporting by providing funding to support ESG reports.

Sustainability practitioners can have an impact by bringing the best practices implemented by airports in other countries to the US. Even airports that have a limited budget and perhaps limited interest from the community can identify projects that make sense and begin to make a difference.

Additional research is recommended to support airport sustainability, including sustainability planning, sustainability activities, and sustainability reporting. Comparative case studies of airport activities would be useful to the research community and to airport practitioners. Further documentation of the challenges and successes related to airport sustainability planning, practices, assessment, and reporting would be very helpful. Comparison of these activities in the US with airports in other countries would also be very useful and would foster a collaborative environment to refine sustainability strategies. Given the wide range of airport characteristics and sustainability and ESG reporting practices at US airports, further research is recommended to document the current practices in greater detail, which will provide a foundation for future recommendations. It would be worthwhile to define the differences in purpose, audience, and legal implications for US large hub and medium airports, analyze the drivers for different reporting characteristics, and assess the reports in terms of completeness, credibility, balance, and specificity.

In the meantime, a lack of a well-defined protocol for ESG reporting should not constrain an airport. One strategy may be to leverage the best practices for sustainability planning as a framework for sustainability reporting. In this context, airports would track activities in the sustainability plan and report on the progress for each activity, utilize their baseline assessment with reporting that frames current performance as measured by their own metrics relative to the baseline assessment, goals, and their year-by-year performance. This approach lays a foundation for assessment, transparency, reporting, and continuous improvement. In any case, lack of a full sustainability framework should not prevent an airport from initiating sustainability activities.

Sustainability will remain an issue for many airports, and while there may be some movement toward a standard framework for sustainability reporting, it is important that the reporting framework allow each airport to feature the unique aspects of their contributions to sustainability and be adaptable to reflect sustainability in the context of the local airport characteristics, including its physical facilities, aeronautical activities, governance structure, environment, social framework, and the unique role it plays to support the community.