Overburdened Communities Highly Impacted by Air Pollution

Web pages we site throughout this StoryMap, such as  EJScreen  and the  Climate and Economic Justice Screening Tool (CEJST) , have been removed from their associated websites as of February 5, 2025. While the original source is no longer available online, the information referenced was accurate at the time it was published.

This StoryMap describes the overburdened communities that the Department of Ecology (Ecology) has identified as highly impacted by air pollution for the " Improving Air Quality in Overburdened Communities " initiative. There is one major exception that communities on Tribal land, managed under the jurisdiction of a federally recognized Tribal government, will only be finalized following Tribal consultation. Ecology is providing this information about our process, rationale, and sources of data in the interest of full transparency.

Documents outlining the communities and how they were identified are available below:

•  Focus Sheet - High-level overview of identified communities
•  Community Summary Report - Information about the overburdened communities that Ecology has identified as highly impacted by air pollution (same content as this StoryMap).
•  Technical Support Document - Technical information that includes indicators, methods, caveats, and data sources used to identify communities.

The  StoryMap of our draft process for identifying communities  provided for the fall 2022 comment period is still available for reference. For questions about this StoryMap, or to request data, see the contact information at the bottom of this page.

The “ Improving Air Quality in Overburdened Communities ” initiative is a new effort to reduce air pollution in Washington communities highly impacted by air pollution. While the  Climate Commitment Act  (CCA) focuses on greenhouse gas emissions, the  Environmental Justice Review  of the CCA also requires that we work to reduce another category of air pollution, called  criteria air pollutants  (carbon monoxide, nitrogen dioxide, lead, ozone, particulate matter, and sulfur dioxide), in overburdened communities highly impacted by air pollution. This law requires us to:

• Identify which Washington communities are overburdened by air pollution and the significant sources of this pollution.
• Expand and improve Washington’s air quality monitoring network to gather more data about the criteria air pollutants that affect these communities.
• Develop strategies to reduce criteria air pollutants in these overburdened communities.
• Conduct periodic analysis to make sure reduction goals for criteria air pollution are being met.

Environmental justice is at the center of this initiative. We are intentionally designing this work to be continuous to incorporate lessons learned, and changes in demographic and air quality data. We will continue to work with Tribes, communities, environmental justice and community-based organizations, the state’s Environmental Justice Council, and others to refine our process every six years.

All communities experience air pollution. However, we recognize that some communities are affected more than others. This disparity could be due to the level of air pollution exposure, the vulnerability of the population to health impacts related to that exposure, the ability of the community to mitigate its effects, or any combination of these factors. The Environmental Justice Review of the CCA requires Ecology to identify “overburdened communities highly impacted by air pollution” ( RCW 70A.65.020 (1)) and to take steps to reduce the disparities in criteria air pollution impacts that these communities face.

 RCW 70A.65.010 (54) defines “Overburdened Communities” as:

“a geographic area where vulnerable populations face combined, multiple environmental harms and health impacts or risks due to exposure to environmental pollutants or contaminants through multiple pathways, which may result in significant disparate adverse health outcomes or effects.”

The intent section of the law, also states that "Under the program, the legislature intends to identify overburdened communities where the highest concentrations of criteria pollutants occur..." ( RCW 70A.65.005 (7)). This means that for the purposes of this work, “overburdened communities highly impacted by air pollution” that Ecology is tasked with identifying, evaluating, and protecting under  RCW 70A.65.020  are considered a subset of all overburdened communities – specifically those that experience the highest concentrations of air pollution. Ecology will conduct environmental justice reviews of air quality and health impacts in these communities and develop strategies to reduce criteria pollution.

Described below are the communities Ecology has identified as overburdened for the purposes of this initiative, including how and why they were identified. These community descriptions are intended to provide key community characteristics and show potentially vulnerable populations and criteria air pollution concerns. These descriptions are based on the best currently available information. They are not comprehensive and are not intended to reflect community assets, complexity, or diversity for any purpose beyond this initiative. In addition, we recognize that these communities likely include multiple smaller communities, neighborhoods, and towns. We drew these communities with contiguous boundaries for the purpose of expanding air monitoring and pollution reduction efforts in a meaningful and coordinated way. Ecology looks forward to engaging with each community to better understand local needs and concerns related to criteria air pollution and finding collaborative solutions to address them.

The law directs us to “identify overburdened communities where the highest concentrations of criteria pollutants occur…” ( RCW 70A.65.005 (7)).  To identify where criteria air pollutant levels are highest, we used the best data currently available. This is a combination of existing air quality monitoring information and extensive computer modeling of pollution concentrations using emissions data, meteorology, topography, and other factors. In general, we included overburdened communities where at least the modeling indicated there is likely an elevated level of criteria air pollution, even if there is not localized monitoring data to verify it. When we conduct more extensive monitoring in these communities, we may find that pollution concentrations are lower or higher than previously understood.

Data and modeling may not fully capture on-the-ground impacts and experiences, especially at a very local or neighborhood level. Furthermore, air quality changes over time, new data become available, and new policies are enacted. We will reevaluate community boundaries and the list of communities identified as overburdened and highly impacted by air pollution every six years, using the more local community air quality data that has become available.

Currently, we have identified 16 overburdened communities highly impacted by air pollution, with more to come following Tribal consultation. These communities represent more than 1.2 million people, or about 15.5% of the population of Washington.

The 16 identified communities (shown on the map below) are a mix of urban, suburban, and rural areas, and range greatly in size of population and geographical area. Community populations range from about 1,500 to more than 200,000 people. By area, the communities range from less than 3 square miles to 173 square miles. These differences reflect the diversity of both the communities themselves and the air pollution concerns they face. Likewise, the approach we take to implement this initiative in each of these communities will have to differ to meet the needs and input of each community.

Download map:  Community Boundary File 

Note: Community boundaries are census block group boundaries, unless otherwise stated. More information about how each community was identified is in the summary for each community below.

To identify these overburdened communities, we started with public engagement in early 2022 to hear about people’s experiences with air pollution across the state and researched how criteria air pollution impacts communities across all of Washington. Next, we looked for data and resources that were available to represent these real-world issues. Then we studied existing approaches and environmental justice tools to identify overburdened or underserved communities, to see where we could apply principles or lessons learned into how we put all the data together to identify communities. Using that initial input and research, we created a draft process to identify communities and held a second public comment period in fall 2022. All comments and feedback were reviewed and considered and several changes were made to the draft process. A summary of changes made and response to comments can be found in the Concise Explanatory Statement document available on our  website .

To be considered an overburdened community highly impacted by air pollution, an area must meet the following conditions, based on data available statewide:

1. Community Indicators: Either have a 9 or 10 ranking on the  Washington Environmental Health Disparities (EHD) map , be in the 90 ^th  percentile or higher of census block groups for the  EJScreen  Demographic Index, or be  Tribal land ; and
2. Air Pollution Indicator: Have an elevated level of one or multiple criteria air pollutants

After identifying where these communities are across the state using statewide data, Ecology looked at additional factors, including regional- and local-level data and public comments, to refine the boundaries of the overburdened communities highly impacted by air pollution. To inform our list of overburdened communities for this initiative, we engaged with Tribes, communities, environmental justice advocates, and the Environmental Justice Council throughout our process. See the Technical Support Document for more details on this process, and its development.

We will provide additional public outreach and begin placing air monitors in the identified communities in early 2023. By the end of 2023, we will publish the first biennial reports on community criteria pollution levels, greenhouse gas emissions, and health impacts.

The Climate Commitment Act also requires Ecology to develop standards and strategies to reduce the criteria air pollution in overburdened communities highly impacted by air pollution. We will use the data in our biennial reports to inform future decision-making and policy development. Ecology’s budget package to develop these standards and strategies was included in the  Governor’s proposed 2023-2025 biennial budget . Pending legislative appropriation, Ecology proposed rulemaking to develop control technology standards using existing authority under the state Clean Air Act. Ecology also proposed a new grant program to target the different types of emission sources that contribute to criteria air pollution in identified communities. Depending on legislative appropriation, Ecology would begin rulemaking and the development of a community centered grant program later in 2023. We look forward to working directly with identified communities on actions to improve air quality.

We are reaching out to Tribal governments for government-to-government consultation about the communities we have identified as highly impacted by criteria air pollution, based on the overlap between Tribal land and elevated levels of air pollution. Ecology is also available for further staff-to-staff engagement and government-to-government consultation for Tribes not identified by Ecology’s process.

We invited government-to-government consultation with all Tribal governments in December 2021 and conducted Tribal meetings in January 2022 and September 2022, prior to each public engagement period. We will continue to consult with Tribal governments and engage organizations affiliated with Washington Tribes throughout every stage of this initiative.

This is a continuous process. We expect both the air quality that communities experience and the availability of data related to environmental justice to change with time. As data are updated and new information is gathered through continued engagement with stakeholders, communities, and Tribes, we may identify new overburdened communities highly impacted by air pollution in the future. New data and information may include updates in environmental justice screening tools, new air monitoring data (including monitoring efforts taken separately from this initiative), air pollution model results, and lessons learned from the  Healthy Environment for All (HEAL) Act  and other efforts to identify overburdened communities. We also may need to adjust the boundaries of identified communities from time to time. We are committed to reevaluating these communities regularly every six years to gauge changes in air quality. Importantly, we do not intend to remove an overburdened classification from identified communities unless air quality targets are met (or there is express direction from a Tribal government to do so regarding Tribal lands).

Please visit  our website  for more information about the Improving Air Quality in Overburdened Communities Initiative, including information about public input opportunities. We provide translated materials in Spanish, Chinese, Korean, Vietnamese, and Russian.

All communities experience air pollution. This effort was focused on identifying communities that are overburdened and highly impacted by criteria air pollution.  Ecology continuously works with local clean air agencies, the EPA, and Tribes to ensure healthy air to breathe for all Washingtonians.  Here is some further information about this work and grant opportunities:

• Air quality information:
  •  Washington’s air quality monitoring network 
  •  Burn bans 
  •  Washington smoke information blog 
  •  Burning & industrial air permits 
  •  Air emissions inventory 
  •  Air quality standards  (for criteria air pollutants and air toxics)
• Ecology administers several air quality  grant programs  that are available to clean air agencies, local and Tribal governments, and other local partners, including wood smoke reduction and clean diesel programs.

Federal programs and initiatives for addressing air quality and environmental justice are also ongoing, including funding through the  American Rescue Plan  and the  Inflation Reduction Act .

For questions about this StoryMap, contact Kirsten Dodroe at kirsten.dodroe@ecy.wa.gov or (564) 669‑9639.