Census Data for Petersburg ...
The last Decennial Census<1> was in 2010, giving Petersburg a population of 2,948 people.
The 2010 Census gave Alaska had a population of 710,231 people, meaning that Petersburg had 0.42% of the total population of Alaska - making it the state's 18th most populous community.
When the Census Bureau conducts a census for a city like Petersburg, they draw a boundary around the area in which they are going to conduct their count - this is called a sampling area (or a polygon). The shape of the sampling area can be quite complex and it's important to keep in mind that the boundaries of the sampling area may or may not match the recognized boundaries of the city.
Things like the population, area and housing for Petersburg reflect the sampling area. Since the shape of the sampling area and the actual boundaries of Petersburg might be slightly different, it's best to check with the U.S. Census Bureau if you need precision.
The 2010 Census shows that the sample polygon for Petersburg has a total area of 45.63 square miles [118.2 km²]. Of this total, 44.13 square miles [114.3 km²] is land, with the balance (3.29%) being water (1.5 square miles [3.9 km²]).
Not only does the sampling area define boundaries, it also has a GPS location (latitude & longitude) that indicates a point within the sampling area (usually at the center of the polygon). At the time of the 2010 Census, the sampling area was located at:
Lat: 56° 45' 47" (or 56.8°) [Map]
Lon: -132° 52' 32" (or -132.88°)
More information on this topic and the changes between the 2000 Census and the 2010 Census can be found in the section for our Census-to-Census Observations ... (see below).
Population Density ...
Using the population (2,948 people) and land area (44.13 square miles [114.3 km²]) values from the 2010 Census, Petersburg had a population density of 64.6 people per square mile [24.94 people/km²].
In comparison, the 2000 Census shows Petersburg had a population of 3,224 people and a land area of 43.86 square miles [113.6 km²]. This gives a population density of 70 people per square mile [27.04 people/km²]
NOTE: Be aware that when comparing population density between the 2000 and the 2010 Census, there were changes in the sampling area for Petersburg. You need to be careful when making such a comparison, the differences are likely to lead to a questionable comparison. More information about the nature of these changes can be found in the section Census-to-Census Observations ... (see below).
Housing Units ...
At the time of the 2010 Census, Petersburg had 1,356 Housing Units<2> and with its population of 2,948 people, this averages 2.17 people per Housing Unit.
The 2010 Census shows Petersburg had a land area of 44.13 square miles [114.3 km²]. This translates to 29.72 Housing Units per square mile [11.47 housing units/km²].
From the Census of 2000: Petersburg had 1,367 Housing Units, a population of 3,224 people and a land area of 43.86 square miles [113.6 km²]. This gives a density of 2.36 people per Housing Unit and 29.69 Housing Units per square mile [11.46 housing units/km²].
NOTE: Repeating the caution above (under Population Density), be aware that when comparing Housing Units between the 2000 Census and the 2010 Census, there were changes in the sampling area for Petersburg and you need to be careful when comparing numbers between the censuses. More information about these differences can be found in the section called Census-to-Census Observations ... (see below).
Census-to-Census Observations ...
When the Census Bureau takes a census count (or enumeration) for Petersburg, they start by specifying the boundaries of the area to be counted. This area (or sampling area) is a polygon and its shape can be quite complex - it may or may not match the geographical boundaries of Petersburg. It's important to note that from one Census to the next, the shape and location of the polygon can change.
If you need precision or details about the methodology of the Census, you should visit the U.S. Census Bureau for a definitive answer.
The sampling area (or polygon) given for the 2010 Census is 0.89% smaller than the 2000 Census.
The 2010 Census shows that the total area for Petersburg was 45.63 square miles [118.2 km²]. Of this total, 44.13 square miles [114.3 km²] is land, with the balance (3.29%) being water (1.5 square miles [3.9 km²]).
The 2000 Census shows a total area of 46.04 square miles [119.2 km²]. Of this total, 43.86 square miles [113.6 km²] is land, with the balance (4.78%) being water (2.18 square miles [5.6 km²]).
While generally coinciding with the GPS location (latitude/longitude) of Petersburg, the latitude and longitude given by the Census Bureau actually indicates the GPS location of the polygon for Petersburg.
For the 2010 Census, the location was given as:
Lat: 56.763209° (or 56°45'47" N) [Map]
Lon: -132.875740° (or -132°52'32" W)
For the 2000 Census, the location given was:
Lat: 56.804414° (or 56°48'15" N) [Map]
Lon: -132.942013° (or -132°56'31" W)
The difference indicates that the U.S. Census Bureau moved the location of the polygon for the 2010 Census 3 miles to the southeast<3> of the location that was used in the 2000 Census.
The U.S. Geological Survey (USGS) and the U.S. Board on Geographic Names (BGN) have assigned a unique GNIS identifier (#2419447) to Petersburg. This identifier also marks a GSP point on the map, and that point lies within the boundaries of Petersburg. The GNIS point has been mapped to the latitude/longitude:
Lat: 56.756156° (or 56°45'22" N) [Map]
Lon: -132.870910° (or -132°52'15" W)
The GSP location given for the 2010 Census lies 2,746 feet to the north<4> of the point given by the GNIS for Petersburg. For more information about this and the relationship of the various Federal Codes, please visit our Misc Page for Petersburg.
Miscellaneous Information for Petersburg ...
The Federal government has assigned various identifying codes to each community, county and state. At one time or another, the US Census Bureau has referenced one (or more) of the following identifiers when referring to either or the city of Petersburg:
The GNIS Codes ...
The current system of identification is called the Geographic Names Information System (GNIS). The following GNIS codes relate to Petersburg:
GNIS ID for Petersburg: 2419447
GNIS ID for Alaska: 1785533
The FIPS Codes ...
An earlier (and largely obsolete) identification method was called the Federal Information Processing Standard (FIPS):
State Code: 02 (Alaska)
Place Code: 60310 (Petersburg)
State & Place Code: 02/60310 (Alaska / Petersburg)
Misc. Census Codes ...
Petersburg is located in Census Region #4 (the West Region) and Division #9 (the Pacific Division).
The US Postal Service ZIP Code ...
While some people have used a ZIP code to identify a community, the purpose of the ZIP code was to make mail delivery more efficient by grouping addresses together. Although the ZIP Code doesn't specifically identify a city like Petersburg, it does identify addresses that are in (or near) Petersburg. It's important to remember that the boundaries of a ZIP Code can be changed, re-assigned or overlapped with other ZIP Codes.
The ZIP code for Petersburg: 99833<5>
Census ZCTA Codes ...
The US Census Bureau created statistical entities that they call ZIP Code Tabulation Areas (ZCTAs) and these ZCTAs are frequently confused with the ZIP codes that come from the US Postal Service (USPS).
ZCTAs were first created for the 2000 Census and at that time, they were based upon the USPS ZIP codes. While largely covering the same areas, the boundaries of a ZCTA do not necessarily match the boundaries of a postal ZIP code with the same number. For example, while a postal ZIP code can cross a county or state line, a Census ZCTA can not. They should be treated as separate entities with no correlation between them.
For more information about the various Federal identification codes, please visit our Misc Page for Petersburg.
|<1>||Every 10 years (eg- 1990, 2000, 2010), the US Census Bureau conducts a Constitutionally-mandated count (or enumeration) of people living within the United States. This count is called a Decennial Census. The last Decennial Census was the 2010 Census, with the next one planned for 2020.|
- Return to Citation
|<2>||A Housing Unit is a broad term for those places where people live (whether occupied or temporarily vacant), such as a house, an apartment, a mobile home, or an area that is considered as a separate living quarter. Separate living quarters (consisting of one or more rooms) are considered to be those places where people live, sleep and eat separately from others and that have access to the outside (either directly or by a shared hallway).|
- Return to Citation
|<3>||The calculated bearing (or the angle) to the 2010 Census location is 221 degrees.|
- Return to Citation
|<4>||The calculated bearing (or the angle) to the GNIS point is 20 degrees.|
- Return to Citation
|<5>||When looking for a ZIP Code, whether Petersburg or elsewhere, it's always best to check the website of the United States Postal Service (USPS).|
- Return to Citation
For additional information, please visit our Glossary for Petersburg.