An interactive map sheds light on which California communities are disproportionately burdened by pollution
Image: OEHHA
CalEnviroScreen was built by the Office of Environmental Health Hazard Assessment (OEHHA), part of the California Environmental Protection Agency. In it, pollution and population data combine to shed light on which communities bear the brunt of environmental and health hazards. Addressing this inequality is known as environmental justice.
“It is both a map and a way to think about the power of maps, in this case facilitating a geographic approach to realize the goals of environmental justice,” explained Stephen Gay, Equity & Social Justice blogger for Esri.
Using modern geographic information system (GIS) technology, CalEnviroScreen ranks and color codes California’s more than 8,000 census tracts to reflect vulnerability to pollution. The formula behind CalEnviroScreen considers the presence of various types of pollution, the prevalence of health problems that can be worsened by pollution, and population data.
The main map shown here illustrates the combined Pollution Burden scores, made up of indicators from the Exposures and Environmental Effects components of the CalEnviroScreen model. In addition to an overall score, CalEnviroScreen provides map-building tools to isolate 21 specific datasets.
Communities with a heavy pollution burden often experience high poverty that makes them more vulnerable to pollution’s effects. Pollution data includes cleanup sites, water quality (such as groundwater contamination, lead exposure, pesticide runoff) and air quality (including traffic exhaust, ozone, particulate matter). Deleterious health effects include asthma, heart disease, low birth weight and more.
The map itself is only the most visible manifestation of CalEnviroScreen, which CalEPA said is a screening methodology “to help identify California communities that are disproportionately burdened by multiple sources of pollution.”