Proposed Urban Area Criteria for the 2010 Census
October 14th, 2010
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Urban and Rural Classification
•
The Census Bureau identifies and classifies urban and rural areas after
each decennial census.
•
Urban areas of at least 2,500 people have been identified since 1906.
•
Urbanized areas of 50,000 or more people were first defined for the
1950 Census. Urban places of at least 2,500 people were identified
outside urbanized areas. Urban clusters of 2,500 - 49,999 were first
defined after Census 2000.
•
The Census Bureau identifies
urban and rural areas solely
for the purpose of tabulating
and presenting statistical
data.
2
Urban Area Definitions
•
Represent densely developed territory, encompassing residential,
commercial, and other non-residential urban land uses in which social
and economic interactions occur.
•
Represent the “Urban Footprint”
•
Structure has been explicitly
defined through measures based
primarily on population counts and
residential population density
•
Criteria have also accounted for
non-residential urban land uses
that are functionally part of the
urban landscape
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Census 2000 Urban Areas
•
For Census 2000, an urban area consists of a densely settled
core created from census block groups, census blocks, and the
adjacent densely settled surrounding territory that together have
a minimum population of 2,500 people
•
There are two types of urban areas: urbanized areas of 50,000
or more population and urban clusters of 2,500 – 49,999.
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Census 2000 Basic Urban Core Delineation
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Census 2000 Basic Urban Core Delineation
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2010 Urban Area Program
•
Remain committed to an objective, equitable, and consistent
nationwide urban area delineation.
•
Retain decennial comparability by building upon 2000 criteria.
•
All potential modifications are refinements, or supplements to
address deficiencies encountered for Census 2000.
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Initial Core Using Census Tract Analysis Units
Qualifying census
tract ≥ 1,000 ppsm
560
ppsm
800
ppsm
Qualifying census
tract ≥ 500 ppsm
contiguous to initial
core
Census tract not
contiguous to an initial
core census tract ≥
1,000 ppsm
550
ppsm
Census tract > 3 sq.
miles
1,600
ppsm
1,300
ppsm
700
ppsm
750
ppsm
Initial Census Tract
Core Based on
Population and Size
Criteria
Boundary Using Proposed Impervious Criteria
Urban Area Boundary Using Impervious Land Cover
2000 Urban Area
Impervious Land Cover
Census Blocks
´
0
0.1
0.2
0.4
Miles
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Initial Core Test Delineation Regions
Tract as Analysis Unit
Population
42,384,952
Land Area
(sq. miles)
14,525
Block Group as Analysis Unit
Number of
Initial
Urban
Cores
924
Population
42,213,521
Land Area
(sq. miles)
15,027
Number of
Initial
Urban
Cores
904
Wetlands as an Additional Exempted Territory
Noncontiguous qualifying
territory
Jump census block
Urban Core
Road connection
Distance from core to
wetlands is 0.7 mile
Distance over
wetlands is 0.5 mile
Distance over
river is 0.6 mile
Distance over
wetlands is 0.7 mile
Distance from wetlands to
noncontiguous qualifying
area is 0.7 mile
Total
exempted
distance
is 1.8
miles
Total
jump
distance
is 3.2
miles
Hop and Jump Corridor Examples
Grand Junction, CO "Sawtooth"
Grants Pass, OR "Fingers"
Jump Blocks
Hop Blocks
Urban Area
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Splitting Large Urban Agglomerations
Census 2000 San Francisco-Oakland and
San Jose Split
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Figure 4: Splitting Large Urban Agglomerations
Urbanized
Area A
after split
Urban
agglomeration
prior to split
Incorporated
or Census
Designated
Place
Metropolitan
Statistical
Area
Boundary
Boundary
splitting the
agglomeration
Urbanized
Area B
after split
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URBAN AREA
DELINEATION
REGION 65
Enclave block
Hop block
Jump block
25 Oct 2010
NOTE:
These cores were generated using
proposed 2010 urban area criteria
with 2000 population and geography
15
0
5 10
20
30 Miles
16
17
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Qualification of Airports for Inclusion in Urban
Areas
Merced Municipal/MacCready Field, Merced CA
Prison Urban Clusters
Abilene North (Robertson Unit), TX
Population: 4,650
Urban: 4,650
Group Quarters: 4,650
Institutional: 4,650
Correctional: 4,650
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Density: 94,589 ppsm
Central Places
The Woodlands, TX
2000 Population: 89445
•
•
Central places are not necessary for
UA or UC delineation
Principal cities defined within CBSAs:
•
•
•
Shenandoah, TX
2000 Population: 1503
Oak Ridge North, TX
2000 Population: 2991
capture same concept
classification based on different
criteria
Lack of consideration of place
boundaries in delineation process
results in central places split between
urban and rural portions.
The Woodlands CDP, TX
2000 Population: 55649
Accokeek CDP, MD
2000 Population: 5057
St. Charles, MD
2000 Population: 74765
Waldorf CDP, MD
2000 Population: 22266
Indian Head, MD
2000 Population: 3422
Bryans Road CDP, MD
2000 Population: 4912
Largest CDP
Incorporated Place
CDP
UA
Bennsville CDP, MD
2000 Population: 6207
St. Charles CDP, MD
2000 Population: 33379
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A Reminder!!!
We are currently seeking input…
Any comments, suggestions, or recommendations concerning
the criteria proposed should be submitted in writing no later than
NOVEMBER 22, 2010
Please submit written comments on the proposed criteria to:
Timothy Trainor
Chief, Geography Division
U.S. Census Bureau
Washington, DC 20233-7400
www.census.gov/geo/www/ua/2010urbanruralclass.html
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Questions? Comments?
Vincent Osier
Chief
Geographic Standards and Criteria Branch
Geography Division
U.S. Census Bureau
Vincent.osier@census.gov
(301) 763-9039
Chris Henrie
Geographic Standards and Criteria Branch
Geography Division
U.S. Census Bureau
christopher.j.henrie@census.gov
(301) 763-9086
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