ETC Explorer

The Justice40 initiative, created by the Biden-Harris Administration through Executive Order 14008 Tackling the Climate Crises at Home and Abroad, is a key component in USDOT’s efforts to confront and address decades of underinvestment.  When decision makers at all levels have the tools to understand how a community is experiencing disadvantage and can identify projects that create benefits that will reverse or mitigate those causes, the result is a higher quality of life and economic prosperity in communities across the country. 

The US DOT Equitable Transportation Community (ETC) Explorer is an interactive web application that uses 2020 census tracts and data, to explore the cumulative burden communities experience, as a result of underinvestment in transportation, in the following five components:  Transportation Insecurity, Climate and Disaster Risk Burden, Environmental Burden, Health Vulnerability, and Social Vulnerability.  It is designed to complement CEQ’s Climate & Economic Justice Screening Tool by providing users deeper insight into the Transportation disadvantage component of CEJST, and the ETC Explorer’s Transportation Insecurity component, which will help ensure the benefits of DOT’s investments are addressing the transportation related causes of disadvantage.  Applicants to USDOT's Justice40 covered program NOFOs should use CEJST as the primary tool to identify disadvantaged communities, as USDOT’s ETC Explorer is not a binary tool indicating whether a census tract is considered disadvantaged; it is a dynamic tool that allows every community in the country to understand how it is experiencing burden that transportation investments can mitigate or reverse.       

ETC Explorer Tools- 

• ETC Explorer - National Results- An interactive dashboard to give users the ability to understand how a community or project area is experiencing transportation disadvantage compared to all other census tracts nationally across the five disadvantage component areas and forty indicators used to develop the five components.  Popup Databoxes provide more specific data on Transportation Insecurity for each census tract. 

• ETC Explorer - State Results- An interactive dashboard to allow users the ability to understand how a community or project area is experiencing transportation disadvantage compared to all other Census Tracts within a state across the five disadvantage component areas and forty indicators used to develop the five components.  Popup Databoxes provide more specific data on Transportation Insecurity for each census tract. 

• ETC Explorer- Add Your Data (National and State Results)- Allows users to add their own data to DOT’s ETC Explorer- National Results and -State Results maps and create custom views that can be exported.  The Add Your Data feature defaults to the National Results map.  To utilize the State Results- map turn on the State Results layer in the layers feature.  

• Transportation Insecurity Analysis Tool (TIAT)- The Transportation Insecurity Analysis Tool visually displays the raw data for a select group of indicators at the state or national level, that reflect transportation insecurity.  This application is an interactive mapping tool to understand where transportation insecurity is most acute in communities across the country.  Users can filter the data via preset thresholds or enter their own.  Additionally, users can select layers such as MPO boundaries, alternative fueling stations, FARS data, transit routes, intercity bus routes or any of the five Disadvantage Components to gain a deeper understanding into the relationship between transportation insecurity and the selected layer.   

• Understanding the Data- Provides descriptions of the tools and methodologies within the ETC Explorer and the five main areas and forty indicators used to measure transportation disadvantage.   

Methodology- 

Please see the Technical Documentation document for more details 

ETC Explorer’s five components of disadvantage and the indicators used to develop them:  

 1. Transportation Insecurity occurs when people are unable to get to where they need to go to meet the needs of their daily life regularly, reliably, and safely. Nationally, there are well-established policies and programs that aim to address food insecurity and housing insecurity, but not transportation insecurity. A growing body of research indicates that transportation insecurity is a significant factor in persistent poverty.  

•  Transportation Access- Communities with higher scores may experience longer commute times and difficulty traveling where they want to go via cars, walking and transit.  Long commute times and limited access to personal vehicles or transit can create significant barriers to employment and resources. 
• Transportation Cost Burden- Communities with higher scores spend a great percentage of household income on transportation, including-transit costs; vehicle maintenance and insurance costs; gasoline and fuel which leaves less money for housing, medical care and food potentially leading to households living in substandard housing with higher rates of chronic illness and obesity. 
• Transportation Safety- Communities with higher score experience higher levels of fatalities per 100,000 persons related to motor vehicle crashes.  For additional safety data please visit https://cdan.dot.gov/query  

 2. The Environmental Burden component of the index includes variables measuring factors such as pollution, hazardous facility exposure, water pollution and the built environment. These environmental burdens can have far-reaching consequences such as health disparities, negative educational outcomes, and economic hardship.   

• Ozone Level- Communities with higher scores experience higher levels of ozone in the surrounding air from sources such as emissions from vehicles and industrial activities.  Transportation activities contribute to this factor by releasing compounds that interact to create ozone. 
• PM 2.5 Level- Communities with her scores experience higher levels of PM 2.5, which is the presence of fine particles or particulate matter (having a diameter of 2.5 micrometers or less) in the surrounding air from sources like burning fossil fuels, vehicle emissions, and road dust. 
• Diesel PM Level- Communities with higher scores experience higher levels of diesel particulate matter (DPM) which are time particles in the air that come from diesel engine exhaust from sources like diesel-powered vehicles, such as trucks and buses, and industrial activities like shipping, construction and mining. 
• Air Toxics Cancer Risk- Communities with higher scores experience higher levels of air toxics in the air from sources like industrial facilities and vehicular emissions, causing health problems such as respiratory issues, heart disease, neurological problems, increased risk of certain cancers, and elevated mortality. 
• Hazardous Sites Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 miles of a hazardous site.  Examples of these sites include brownfields and superfund sites which have been identified by the Environmental Protection Agency as contaminated by hazardous materials. 
• Toxics Release Sites Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 mile of a toxic release site.  These sites are listed under the Environmental Projection Agency’s Toxic Release Inventory and are defined as having 10 or more full-time explores and either manufacture or use more than a specified amount of toxic chemicals.  Living close to TRI sites and other noxious land uses can result in increased stress from noise and odor. 
• Treatment & Disposal Facility Proximity- Communities with higher scores have a great percentage of their census tracts within 1 mile of a site responsible for handling hazardous waste.  These sites may generate volatile substances. 
• Risk Management Sites Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 mile of a risk management plan site.  These facilities handle highly toxic or flammable chemicals and communities should have evacuation plans in place for responding to worst-case scenarios such as fires or explosions. 
• Coal Mine Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 mile of a coal mine, which tend to have high air pollution concentrations caused by mining activities. 
• Lead Mines Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 mile of a lead mine, which tend to release contaminated soil and dust into the environment. 
• Pre-1980’s Housing- Communities with her scores have a greater percentage of housing units built before 1980.  The presence of older housing, built before 1980, is a predictor of potential lead exposure.  
• High Volume Road Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 mile of high-volume roads (functional classification 1-3).  Proximity to high-volume roads, including interstates, is often lined to higher levels of ozone, diesel PM and increased noise pollution. 
• Railways Proximity- Communities with higher scores have a greater percentage of their census tracts within 1 mile of railways and tend to experience higher levels of noise pollution. 
• Airports Proximity- Communities with higher scores have a greater percentage of their census tracts within 5 miles of airports and tend to experience higher levels of noise and air pollution. 
• Ports Proximity- Communities with higher scores have a greater percentage of their census tracts within 3 miles of ports and tend to experience higher levels of air and noise pollution, as well as the potential for chemical spills. 
• Impaired Surface Water- Communities with higher scores have a greater percentage of their census tracts’ watershed area classified as impaired.  An impaired body of water is one that does not meet water quality standards for designated uses, such as fishing or swimming, as set by the state or tribe with jurisdiction over the water.  High levels of water pollution can result from a variety of sources, including industry, agriculture, and urban runoff.

 3. Social Vulnerability is a measure of socioeconomic indicators that have a direct impact on quality of life. This set of indicators measure lack of employment, educational attainment, poverty, housing tenure, access to broadband, and housing cost burden as well as identifying household characteristics such as age, disability status and English proficiency.   

• 200% of Poverty Line- Communities with higher scores have a greater percentage of population with incomes below 200% of the federal poverty level dependent on household size and location (i.e., in all states except AK and HI in 2020, a single person would be at 200% of the federal poverty line with an annual income of $25,520 while a family of four would earn $52,400) 
• No HS Diploma- Communities with higher scores have a greater percentage of population over the age of 25 with less than a high school diploma which can have a negative impact on their ability to access job opportunities and higher wages. 
• Unemployment- Communities with higher scores have a greater percentage of population over the age of 16 who are unemployed. 
• House Tenure- Communities with higher scores have a greater percentage of houses that are renter occupied. 
• Housing Cost Burden- Communities with higher scores have a greater percentage of houses where the cost of housing is more than 30% of household income.  When people spend a large portion of their income on housing, they have fewer resources to invest in other necessities like food, healthcare, and transportation.  As a results, households may be unable to purchase cars or pay for public transportation, severely limiting their access to education, employment and other essential services.  
• Uninsured- Communities with higher scores have a greater percentage of the population who are uninsured. 
• Lack of Internet Access- Communities with higher scores have a greater percentage of households with no internet subscription.  The absence of internet access hampers an individual’s ability to seek job opportunities, education and other essential services, leading to a hindrance in their participation in decision-making processes and staying informed about environmental issues in their community. 
• Endemic Inequality- Communities with higher scores have a larger income gap between rich and poor, indicating unequal distribution of wealth and limited access to resources for low-income households. 
• 65 or older- Communities with higher scores have a greater percentage of population aged 65 or older.  This is an important consideration when assessing socioeconomic vulnerability, as older populations frequently face access barriers to healthcare and other essential services. 
• 17 or younger- Communities with higher scores have a greater percentage of population aged 17 or younger.  It is important to understand their concentration in a community because people under 17 tend to be more vulnerable to environmental and health issues. 
• Disability- Communities with higher scores have a greater percentage of population with a disability.  Built environments and transportation infrastructure can result in inaccessibility to essential services and resources such as healthcare, transportation, and employment for people with disabilities.   
• Limited English Proficiency- Communities with higher scores have a greater percentage of population over the age of 5 with limited English proficiency.  Those with limited English proficiency can experience a lack of access to information.  For example, because emergency information is frequently communicated only in English, non-English speaking communities are vulnerable and can lack access to critical information needed to stay safe.   
• Mobile Homes- Communities with higher scores have a greater percentage of housing units that are mobile homes. 

 4. The Health Vulnerability category assesses the increased frequency of health conditions that may result from exposure to air, noise, and water pollution, as well as lifestyle factors such as poor walkability, car dependency, and long commute times. 

• Asthma Prevalence- Communities with higher scores have a greater percentage of population diagnosed with asthma.  Exposure to pollutants such as PM 2.5, ozone, and diesel particulate matter can lead to inflammation of their airways, exacerbating asthma symptoms. 
• Cancer Prevalence- Communities with higher scores have a greater percentage of population diagnosed with cancer.  Long-term exposure to pollution can be associated with an increased risk of cancer. 
• High Blood Pressure Prevalence- Communities with higher scores have a greater percentage of the population diagnosed with high blood pressure.  Lack of active transportation options and exposure to air pollutants can increase the risk of developing high blood pressure. 
• Diabetes Prevalence- Communities with higher scores have a greater percentage of population diagnosed with diabetes.  Lack of active transportation options and exposure to PM 2.5 can increase the risk of developing diabetes. 
• Low Mental Health Prevalence- Communities with higher scores have a greater percentage of population reported with low mental health.  Lack of active transportation options and exposure to pollution can have negative impact on mental health. 

5. Climate and Disaster  Risk Burden reflects sea level rise, changes in precipitation, extreme weather, and heat which pose risks to the transportation system. These hazards may affect system performance, safety, and reliability. As a result, people may have trouble getting to their homes, schools, stores, and medical appointments.    

• Anticipated Changes in Extreme Weather (Future Extreme Weather Risks)- Communities with higher scores will likely in the future experience an increased frequency and severity of extreme weather events such as heat waves, heavy rainfall, droughts, and coastal flooding.
• Annualized Disaster Losses (Annualized Losses Due to Hazards)- Communities with higher scores have had a higher yearly financial loss due to climate- related hazards such as floods, hurricanes and severe weather events, as defined by the Federal Emergency Management Agency (FEMA).
• Impervious Surfaces (from Land Cover)- Communities with higher scores have a higher percentage of impervious surfaces, such as roads and parking lots, which can have a variety of negative consequences, especially in communities that are already disproportionately exposed to environmental burdens.  These surfaces generate and amplify head islands, resulting in poor air quality and an increased risk of heat-related illnesses and death.

Transportation Insecurity Indicators 

Environmental Burden Indicators 

Health Vulnerability Indicators 

Social Vulnerability Indicators 

Climate and Disaster Risk Burden Indicators 

ETC Explorer National Results and State Results Methodology 

Graphical Representation of Model

​

​USDOT’s ETC Explorer calculates the cumulative impacts of transportation disadvantage across 85.5 thousand 2020 census tracts.  The data was normalized using min-max scaling, which transforms the data into a standard range, 0 to 1, to enable a comparison and eliminate the effect of different units of measurement.  

​​The five components — Transportation Insecurity, Health Vulnerability, Environmental Burden, Social Vulnerability, and Climate and Disaster Risk Burden — are calculated by summing the ranked normalized indicators for each component. The result is a composite score for each component.  

USDOT then uses percentile ranking to determine each census tracts component score against all other census tracts- 

• Nationally in the National Results dashboard; and 
• Statewide in the State Results dashboard.

Census tracts in the 0 percentile are the lowest disadvantaged and those in the 100th percentile are the most disadvantaged.  This allows USDOT to gauge the relative performance of each census tract per component.  DOT considers a census tract to be experiencing disadvantage if the overall index score places it in the 65th percentile (or higher) of census tracts. The 65th percentile (65%) cutoff was chosen to be consistent with CEJST, which prioritizes tracts at the 65th percentile or above for CJEST’s low-income indicator and verified as the appropriate cutoff for the ETC Explorer through sensitivity analyses.    

The ranked Component Scores are then summed across all components to generate an Overall Score.  The Transportation Insecurity component was double weighted in generating the final score in response to comments received through the RFI process and extensive sensitivity analyses. 

The Overall Score is then again percentile ranked to generate the Final Index Score rank.  This allows DOT to determine how the overall score of a given census tract compares to all the other census tracts- 

• Nationally in the National Results dashboard; and 
• Statewide in the State Results dashboard.

The benefit of this methodology is that it offers a deeper insight into the interactions between different factors that contribute to transportation disadvantage, allows more flexibility to qualify as disadvantaged and measures cumulative impacts. Cumulative impacts are the combined result of multiple environmental, social, or economic impacts. They can be positive or negative and may unfold over time, across locations, or through various activities. The combined impacts can often have a more significant effect than the sum of individual impacts. By examining cumulative impacts, DOT can identify the communities experiencing the highest combined burdens and funding applicants can begin to target projects to best benefit their community.

Transportation Insecurity Analysis Tool

Transportation Insecurity Analysis Tool (TIAT)- The Transportation Insecurity Analysis Tool displays selected transportation insecurity data at the state or national level. ​ Users can filter the data via preset thresholds or enter their own.  Additionally, users can select layers such as MPO boundaries, alternative fueling stations, safety data, transit routes, intercity bus routes, or any of the five Disadvantage Components to gain a deeper understanding into the relationship between transportation insecurity and the selected layer. 

TIAT Filters-

• Urbanized Areas indicate whether a tract contains all, or a portion of, an Urban Area (UZA) with the following population sizes.  
  • Less than 50k (Definition of ‘Rural’ for most USDOT programs) 
  • Between 50k-200k (Included in definition of ‘Rural’ for RAISE) 
  • Greater than 200k 
• Percent of Population at or Below 200% of the Federal Poverty Line indicates the percentage of a population within a tract that is at or below 200% of the federal poverty line. Communities with higher percentages have a greater percentage of population with incomes below 200% of the federal poverty level dependent on household size and location (i.e., in all states except AK and HI in 2020, a single person would be at 200% of the federal poverty line with an annual income of $25,520 while a family of four would earn $52,400).  
  • Less than 20%,  
  • Between 20%-29.9% 
  • Between 30% and 39.9% 
  • Greater than 40% 
• Median Household Income indicates the median income of households within the tract, broken into the following categories.  
  • Between $0-42,731 
  • Between $42,732-$56,010 
  • Between $72,321-$98,194 
  • Greater than $98,195 
• Transportation Cost Burden measures a tract’s average spend on transportation as a percentage of household income. The percentage households spent on transportation are presented in the following categories. 
  • Less than 15% 
  • Between 15%-19.9% 
  • Between 20% and 24.9% 
  • Between 25% and 29.9% 
  • Greater than 30% 
• Estimated cost of transportation measures the amount an average household in the selected tract spends on transportation. The cost is broken into the following categories. 
  • Less than $10,000 
  • Between $10,000-$10,999 
  • Between $11,000-$11,999 
  • Between $12,000-$12,999 
  • Between $13,000-$13,999 
  • Greater than $14,000 
• Housing Cost Burden measures the percent of households within the tract spending 30% or more of their income on housing. The following categories represent the percent of households in a tract exceeding 30% of income spent on housing.  
  • Less than 15% 
  • Between 15%-24.9% 
  • Between 25% and 34.9% 
  • Greater than 35% 
• Estimate of households without vehicles indicates the estimated number of households within the tract without a vehicle.  
  • Less than 50 
  • 50-99 
  • 100-149 
  • 150-249 
  • Greater than 250 
• Transit Availability measures the frequency of transit service per square mile within the tract, as reported by the EPA Smart Location Database. Tracts without any data reported are categorized as “no data reported.” Some of these tracts may have transit service that is not reported to USDOT. Tracts with data reporting are broken into thirds based on transit frequency and categorized as some transit, moderate transit, or lots of transit. 
  • No data reported 
  • Some transit 
  • Moderate transit 
  • Lots of transit 
• Drive Time to POIs were estimated by calculating the average drive time on a Tuesday at 8am from all block group centroids in a tract to the nearest two points of interest. The following points of interest were measured: Adult Education (e.g., colleges, trade schools), Grocery Stores, Medical Facilities, and Parks. Average drive time to the POIs are presented within the following categories. 
  • Less than 15 minutes 
  • 15-29 minutes 
  • 30-60 minutes 
  • Greater than 60 minutes 
• Walk Times to POIs were estimated by calculating the average walk time from all block group centroids in a tract to the nearest two points of interest The following points of interest were measured: Adult Education (e.g., colleges, trade schools), Grocery Stores, Medical Facilities, and Parks. Average walk time to the POIs are presented within the following categories. 
  • Less than 5 minutes  
  • 5-14 minutes 
  • 30-60 minutes 
  • Greater than 30 minutes 
• Broadband Access Categories indicates the percentage of households within the tract with no broadband internet service. The percentages are broken out into the following categories.  
  • Less than 5% 
  • Between 5%-14.9% 
  • Between 15%-24.9% 
  • Greater than 25% 
• Fatalities are based on the 2017-2021 fatality analysis report system data and the fatality rate per 100k people is broken out into quartiles for tracts experiencing at least one fatality over the time period.  
  • Zero 
  • Low 
  • Average 
  • Above Average 
  • High 

TIAT Indicators and Filters 

Popup Databoxes 

​The raw data for a select group of indicators, that reflect transportation insecurity, are reflected in popup databoxes for each Census Tract.  Users can select a single Census Tract or project area to view the data for each Census Tract in the selected area.  (Users can zoom into map for Census Tract number to appear on the map) 

​

Urbanized Area Summary

Tract contains all or a portion of an Urban Area (UZA) with the following population sizes:  

• UZA Population 50k or Less - (Yes/No) 
• UZA Population 200k or Less - (Yes/No) 
• UZA Population 200k+ -  (Yes/No) 

Cost Burden Summary 

• Poverty Level – “X”% of population in the tract living at or below 200% of the federal poverty line. 
• Median Household Income - The median household income in this tract is $“X” 
• Transportation Cost Burden - The average household in this tract spends “X”% of their household income on transportation. 
• Estimated Cost of Transportation - The average household in this tract spends an estimated $“X” on transportation. 
• Housing Cost Burden - “X”% of households in this tract spend more than 30% of their income on housing. 

Access Burden Summary 

•  Number of Households with no Personal Vehicle- An estimated “X%” of households within this tract do not own vehicles.  
• Transit Availability - Transit availability in this tract is “X”.  
• Estimated Drive Distances - Estimated drive distances to various points of interest are summarized below: 
  • Adult Education - “X” minutes 
  • Grocery Stores - “X” minutes 
  • Medical Facilities - “X” minutes 
  • Parks - “X” minutes 
•  Points of Interest within a 15 Minute Walk? 
  • Adult Education – (Yes/No)  
  • Grocery Stores - (Yes/No)  
  • Medical Facilities - (Yes/No)  
  • Parks - (Yes/No) 

 Broadband Access- X% of households in this tract lack internet access. 

Safety Summary 

• Total Fatalities - Traffic fatalities in this tract are estimated to be “X” per 100k people between 2017-2021.  
  • Please note- TIAT popup databoxes include the additional data fields for safety.
    • Total Fatalities
    • Total Motorist Fatalities
    • Total Cyclist Fatalities
    • Total Pedestrian Fatalities
    • Total Other Fatalities

Resources

For additional instructions on how to use the ETC Explorer, download the User Guide here:  

• English- View the ETC Explorer User Guide in English.

• Spanish- View the ETC Explorer User Guide in Spanish.

5 Minute video tutorial on how to use the ETC Explorer- National Results dashboard (the State Results dashboard is used the same as the National Results tool): 

• English-   Watch the video in English.

• Spanish- Watch the video in Spanish.

Video tutorial on how to use the Transportation Insecurity Analysis Tool: 

• English- Coming soon 

• Spanish- Coming soon 

The Justice40 Story Map, which describes DOT’s approach to Justice 40 including three case studies. The Story Map uses the ETC Explorer to demonstrate the connection between the components of disadvantage for the case studies and project benefits that may help reverse or mitigate how a community experiences disadvantage Justice40 at USDOT (arcgis.com) 

Further documentation on ETC Explorer’s index methodology and underlying components can be found here: “ETC Explorer Technical Documentation” 

Access to the ArcGIS Disadvantage Index layer can be accessed via a “feature service” or downloaded in various formats (csv, excel, geodatabase, shapefile)  

• ETC Explorer Technical Documentation
• DOT Index
• DOT Index State
• DOT Index (.zip)
• DOT Index State (.zip)
• DOT Index (.csv)
• DOT Index State (.csv)
• Data Dictionary (.xlsx)
• Graphic

DOT Disadvantage Census Tracts National Results Feature Service: link is below

https://services.arcgis.com/xOi1kZaI0eWDREZv/arcgis/rest/services/DOT_Disadvantage_Census_Tracts/FeatureServer

DOT Disadvantage Census Tracts State Feature Service: link is below

https://services.arcgis.com/xOi1kZaI0eWDREZv/arcgis/rest/services/DOT_Disadvantage_Census_Tracts_State_Results/FeatureServer

Questions or technical assistance requests can be sent to Justice40@dot.gov