From the AAG Discussion List:
The Census Bureau published proposed criteria for census tracts, block groups, census designated places (CDPs), and census county divisions (CCDs-defined in 22 states as the statistical equivalents of minor civil divisions) for the 2010 Census in the Federal Register on April 6, 2007. All interested individuals and organizations are invited to review and comment, as appropriate, on the proposed criteria for these statistical areas. Each of the Federal Register notices is available on the Census Bureau’s Participant Statistical Areas Program website at
General information about the 2010 Participant Statistical Areas Program is available on the Census Bureau’s website at http://www.census.gov/geo/www/psap2010/psap2010_main.html.
Requests for additional information about these statistical areas as well as copies of the proposed criteria Federal Register notices should be directed to Michael Ratcliffe, Chief, Geographic Standards and Criteria Branch, Geography Division, U.S. Census Bureau, via e-mail at firstname.lastname@example.org or telephone at 301-763-3056.
Comments on the proposed criteria for these statistical areas should be provided in writing to the Director, U.S. Census Bureau, Room 8H001, Mail Stop 0100, Washington, DC 20233-0001. Written comments must be submitted on or before July 5, 2007.
In summary, the proposed changes to the criteria for census tracts, block groups, CDPs, and CCDs are:
- Lower the minimum population threshold for most tracts to 1,200.
- Housing units counts may be used in addition to meet tract thresholds.
- All types of populated tracts should meet the same thresholds.
- Wherever possible census tracts should conform to American Indian reservations.
- Special tracts may be created for large special land use areas without housing units or population.
- Increase the minimum population threshold to 1,200.
- Housing units counts may be used to meet block group thresholds.
- All types of populated block groups must meet the same threshold.
- Wherever possible block groups should conform to American Indian reservations.
- Special BGs may be created for large special land use areas without housing units or population.
- A CDP cannot have zero population and zero housing units.
- A CDP cannot be coextensive with a governmentally active minor civil division (i.e., town, township, charter township, plantation). This change will reduce redundancy in place and county subdivision data tabulations for the following states: Connecticut, Maine, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Wisconsin.
- A CDP must represent a single, distinct community. A CDP that represents multiple, distinct communities, and the hyphenated name typically assigned to represent such CDPs, will not be permitted. Exceptions will be made for communities whose identities have merged and in which both names commonly are used together.
- The Census Bureau is questioning whether to retain or eliminate CCDs as geographic entities. If eliminated, CCDs would not be replaced by other sub-county geographic entities.