There are a number of reasons for the CDP designation: • The area may be more urban than its surroundings, having a concentration of population with a definite residential nucleus, such as
Whitmore Lake, Michigan;
Hershey, Pennsylvania;
Metairie, Louisiana; and
The Villages, Florida (the latter CDP covering only a portion of the overall community). • A formerly incorporated place may disincorporate or be partly
annexed by a neighboring town, but the former town or a part of it may still be reported by the census as a CDP by meeting criteria for a CDP. Examples are the former village of
Covedale (village in Ohio), compared with
Covedale (CDP), Ohio, or the former village of
Seneca Falls (CDP), New York, disincorporated in 2011. • The area may contain an easily recognizable institution, usually occupying a large land area, with an identity distinct from the surrounding community. This could apply to some college campuses and large
military bases (or parts of a military base) that are not within the limits of any existing community, such as
Notre Dame, Indiana;
Stanford, California (which houses the academic core of the
Stanford University campus);
Fort Campbell North, Kentucky; and
Fort Leonard Wood, Missouri. • In other cases, the boundary of an incorporated place may bisect a recognized community. An example of this is
Bostonia, California, which straddles the city limits of
El Cajon. The
USGS places the nucleus of Bostonia within El Cajon. The Bostonia CDP covers the greater El Cajon area in unincorporated
San Diego County that is generally north of that part of Bostonia within El Cajon. • In some states, a CDP may be defined within an incorporated municipality that (for the purposes of the census) is regarded as a
minor civil division. For example, all
towns in New England are incorporated municipalities, but may also include both rural and urban areas. CDPs may be defined to describe urbanized areas within such municipalities, as in the case of
North Amherst, Massachusetts. •
Hawaii is the only state that has no incorporated places recognized by the U.S. Census Bureau below the county level. All data for places in Hawaii reported by the census are CDPs. • A few CDPs represent an aggregation of several nearby communities - for example,
Shorewood–Tower Hills–Harbert, Michigan, or
Egypt Lake-Leto, Florida. However, the Census Bureau discontinued this method for most CDPs during the
2010 census. • In rare cases, a CDP was also defined for the urbanized area surrounding an incorporated municipality, but which is outside the municipal boundaries, for example,
Greater Galesburg, Michigan, or
Greater Upper Marlboro, Maryland. This practice was discontinued in
2010. • In some states, the Census Bureau designates entire minor civil divisions (MCD) with an urban or suburban character as CDPs. Examples include
West Bloomfield Township, Michigan (now listed as a
Charter township) or
Reading, Massachusetts (listed as a
New England town and as a CDP). Such designations were used in states where the MCDs function with strong governmental authority and provide services equivalent to an incorporated municipality (New England, New York, New Jersey, Pennsylvania, Michigan, Minnesota, and Wisconsin). MCDs appear in a separate category in census data from places (i.e., incorporated places and CDPs); however, when MCDs strongly resemble incorporated places, CDPs coterminous with the MCDs are defined so that such places appear in both categories of census data. ==Criteria==