High Population Areas (HPA) Data
The High Population Areas (HPA) data is derived from the U.S. Census Bureau's TIGER Urban Areas data layer, which is reproduced with every decennial census and downloaded
from the Census website. Within the Urban Areas data layer,
features defined as Urban Areas containing 50,000 or more people with a population density of at least 1,000 people per square mile were extracted
to become the "High Population Areas" data layer. A separate Excel table includes the 2020 Census population and population density for each HPA.
Depending on the version, the metadata is included as an .XML file within the downloadable Esri Shapefile or as an independent link.
Other Populated Areas (OPA) Data
The Other Populated Areas (OPA) data is derived from the U.S. Census Bureau's TIGER Designated Places (CDP)/Incorporated Places data layer,
which was downloaded from the Census website. Census Urban Areas (High Population Areas)
were erased from the CDP/Incorporated Places data layer using the Esri ArcGIS ERASE command. The resultant data layer represents the "Other Populated Areas" data layer.
Other Populated Areas are all CDP/Incorporated Places that lie outside of the boundaries of Census Urban Areas containing 50,000 or more people with a population density of at least 1,000 people per square mile.
Depending on the version, the metadata is included as an .XML file within the downloadable Esri Shapefile or as an independent link. For Version 2 of the data, a PDF map is available for download.
