Clean Energy Transformation Act – Cumulative Impact Analysis


In 2019, the Washington State Legislature passed the Clean Energy Transformation Act (CETA), which commits Washington to an electricity supply free of greenhouse gas emissions by 2045.

As directed by CETA, the Washington State Department of Health (DOH) developed a cumulative impact analysis (CIA) in order to designate communities highly impacted by climate change and fossil fuel pollution.

RCW 19.405.140 states:

“By December 31, 2020, the department of health must develop a cumulative impact analysis to designate the communities highly impacted by fossil fuel pollution and climate change in Washington. The cumulative impact analysis may integrate with and build upon other concurrent cross-agency efforts in developing a cumulative impact analysis and population tracking resources used by the department of health and analysis performed by the University of Washington department of environmental and occupational health sciences.”

The goal of designating highly impacted communities is to highlight communities that are currently experiencing a disproportionate share of environmental risk factors and that must, according to CETA, benefit equitably from the transition to a clean energy economy.

Definition of Highly Impacted Community

The Department of Health designates as a highly impacted community any census tract with a 9 or 10 overall rank on the Environmental Health Disparities (EHD) map, or any census tract with tribal lands. For the purposes of designating highly impacted communities, the EHD map is the CIA referenced under RCW 19.405.140, as explained more below.

Instructions for Utilities

View our instructions for utilities to find the data needed for compliance with CETA requirements.

Why use the EHD map for the CIA?

The Department of Health decided to use the EHD map to designate highly impacted communities under the CETA-CIA. The EHD map ranks the risks communities face from environmental burdens including fossil fuel pollution and vulnerability to climate change impacts that contribute to health inequities. It is a well-known vulnerability index for environmental health disparities, and is being used by other state processes to guide funding to reduce environmental health disparities.

The EHD map is based on a conceptual formula of Risk = Threat x Vulnerability. Threat is comprised of both environmental effects and exposures, and vulnerability is comprised of socioeconomic factors and sensitive populations.

The environmental health disparities map uses the model that threat times vulnerability equals risk.

Fossil fuel pollution in Washington is primarily from several air pollutants, particularly particulates, ozone, and nitrogen oxides. Current exposures for these pollutants and populations living near roadways (a major location of exposure) are captured in the EHD map. The map also includes vulnerability measures that are related to fossil fuel pollution, as shown in the diagram below.

Not every measure included in the EHD map is directly related to fossil fuel pollution or climate change effects. The EHD map was developed with considerable input from community organizations and validated through a literature review and statistical analysis by the University of Washington. Changing the composition of the measures would compromise the validity of the statistical analysis, and literature review and the expertise added by the lived experience contributions provided through community engagement.

Climate change measures are not currently included in the overall rankings in the EHD map. However, the map still represents communities that are highly vulnerable to future climate change impacts, because current population vulnerability correlates with the health impacts for most climate hazards.

A “Climate Projections ~2050” overlay map has been added to the EHD map, which includes four climate measures. For a full description of the four climate change projection measures and how to access them, see the Climate Projections web page and instructions.

Limitations of the Clean Energy Transformation Act Cumulative Impacts Analysis

The Washington Tracking Network requires that included data meet three criteria:

  1. The data must be representative statewide.
  2. The data must come from a reliable source that is regularly updated and maintained.
  3. The data must be science-based and backed by a thorough literature review.

Highly impacted communities are identified in this map using the EHD map ranking, as communities highly impacted by current environmental justice issues are also more likely to experience greater impacts from current and future climate change.

The climate projection measures are not currently used to identify highly impacted communities, as they currently include only temperature and precipitation data and do not encompass the full range of anticipated impacts. Other important climate change impacts, such as flooding, wildfire risk, and zoonotic diseases (such as illnesses from insects and rodents) are being evaluated for inclusion at a future date.

Mapping the health-related impacts of climate change using climate projection data is an emerging field. There is currently a lack of literature to support the inclusion of these future projections into mapping tools with current population and health data at this time.

More work is needed in order to add additional climate projection measures to the Washington Tracking Network and to determine how and if these data can be combined.

Definitions of Terms

Census tract – an area designated by the U.S. Census Bureau. Census tracts vary in size depending on how many people live there and are designed to include people with similar population characteristics, economic statuses, and living conditions. Census tracts have on average around 4,000 people. Washington state has 1,458 census tracts.

CETA – Clean Energy Transformation Act requires Washington electric utilities to be 100% carbon-free by 2045 and to ensure an equitable distribution of benefits and reduction of burdens to highly impacted communities (as well as vulnerable populations), as guided by DOH designation of “highly impacted communities.” Read RCW 19.405.

Cumulative impact analysis (CIA) – an analysis of the combined risks to human health or the environment from multiple causes.

Environmental Health Disparities Map (EHD) – an existing tool created by DOH and others that ranks environmental health disparities by census tract. It is an interactive tool that combines the most comprehensive data available to rank Washington communities according to the risk each faces from environmental factors that influence health outcomes. The EHD includes fossil fuel exposure as well as social and health vulnerability measures. Watch the Environmental Health Disparities Map video for detailed instructions.

Environmental hazard – a specific source or concentration of pollution in the environment. Polluted air, water and soil are examples of environmental hazards.

Highly Impacted Community – a community designated by the Department of Health based on cumulative impact analyses in RCW 19.405.140 or a community located in census tracts that are fully or partially on "Indian country" as defined in 18 U.S.C. Sec. 1151. census tracts with an overall rank of 9 or 10 on the EHD map as highly impacted.

Measures – raw data for individual indicators. DOH organizes the data on the EHD map into Measures > Themes > and Topics. Measures are the data for one variable, such as Median Income. Multiple measures are combined to create themes, and themes are combined to create topics. Each measure can be viewed in the map or on the query portal for more detail. Click the chart icon next to the measure on the map to view the same measure in the query portal.

Overlay map – additional information that can be layered on top of the topic map, found under the Map Features tab. Multiple overlay maps may be selected simultaneously. Relevant overlays include utility and tribal boundaries, as well as climate projection data. When a boundary overlay is in use, individual census tracts cannot be selected.

Query portal – one of the tools on the Washington Tracking Network that houses the raw data for measures. Data are available as tables, charts, or maps, and can be downloaded.

Risk – the combination of hazards and vulnerability to those hazards; how likely it is that exposure to environmental hazards will result in poor health for a population.

Sensitive populations – groups experiencing a biological condition that increases susceptibility to environmental factors that may lead to increased negative health outcomes.

Socioeconomic factors – a combination of social and economic factors, such as the education, income, and work status of individuals or communities that may influence their environmental risk.

Theme – a group of similar measures. DOH organizes the data on the EHD map into Measures > Themes > and Topics. Measures are the data for one variable, such as Median Income. Multiple measures are combined to create themes, and themes are combined to create topics. On the EHD map, “environmental effects” is an example of a theme.

Threat – an external condition that increases the chance for a negative health outcome, such as pollution. Threats on the EHD map include a combination of environmental effects and environmental exposures in communities.

Topic map – the overall map for a group of measures, such as Environmental Health Disparities. DOH organizes the data on the EHD map into Measures > Themes > and Topics. Measures are the data for one variable, such as Median Income. Multiple measures are combined to create themes, and themes are combined to create topics. Incorporated data can be drilled into, and additional data can be layered on top.

Tribal lands - on the EHD map, DOH uses a tribal map boundary layer from the Department of Ecology. This layer includes the following types of tribal lands:

  1. Reservation – officially recognized tribal reservation (U.S Bureau of Indian Affairs)
  2. Disputed lands – lands designated as being part of a reservation, but the title is disputed by other parties (U.S Government)
  3. Off-reservation tribal lands – lands outside of a reservation acquired by or held in trust for tribal use (county parcel layers)

The layer does not include ceded lands, rescinded reservation lands or non-treaty lands.

Vulnerability – a person's (or population's) situation, comprised of socioeconomic factors and biological sensitivities, that affects their ability to cope with risk factors. Examples of vulnerability include low birth weight, low income, language barriers, or poor access to health care.


This work is the result of a collaborative effort among: University of Washington's Department of Environmental and Occupational Health Sciences, University of Washington's Climate Impacts Group, University of Washington's Center for Health and the Global Environment, Front and Centered, Washington State Department of Health, Washington State Department of Commerce, and Washington Utilities and Transportation Commission.

Additional Resources

Washington Department of Commerce CETA site

Utilities and Transportation Commission CETA site

CETA: A Brief Overview (PDF)

Environmental Health Disparities Map Technical Report (PDF)

Front and Centered

University of Washington's Department of Environmental and Occupational Health Sciences

University of Washington's Climate Impacts Group

University of Washington's Center for Health and the Global Environment