ETC Explorer Indicators

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 

Transportation Insecurity Indicators 

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.  Together with PM2.5, ozone is a major contributor to air pollution-related morbidity and mortality.
• PM 2.5 Level- Communities with higher 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 tiny 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 Protection 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.

Environmental Burden Indicators

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 levels of inequality as measured by the Gini index can indicate that a significant portion of the population is struggling to meet basic needs and access essential resources, while a small portion of the population is enjoying significant benefits and privileges.
• 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. 

Social Vulnerability Indicators

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 PM2.5, 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 PM2.5 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. 

Health Vulnerability Indicators

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.    

• 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).
• Future Climate and Disaster Risk Burden- Communities with higher scores have greater projected heat and precipitation levels.
• 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.

Climate and Disaster Risk Burden Indicators