Census Data for Kelso
Population ...
The most recent Census Estimate<1> was for 2019 and it gave Kelso a population of 12,393 people.
The last Decennial Census<2> was in 2010, which gave Kelso a population of 11,925 people.
The city of Kelso is located in Cowlitz County. The 2010 Census gave Cowlitz County; a population of 102,358 people. This means that Kelso had 11.65% of the county's total population, making it Cowlitz's 2nd most populous community.
At the same time, Washington had a population of 6,724,540 people, meaning that Kelso had 0.18% of the total population of Washington - making it the state's 68th most populous community.
Area ...
The 2010 Census shows that the sampling area for Kelso has a total area of 8.5 square miles [22 km²]. Of this total, 8.14 square miles [21.1 km²] is land, with the balance (4.18%) being water (0.35 square miles [0.9 km²]).
Cowlitz County has a land area of 1,140 square miles [2,952.9 km²]. At 8.14 square miles [21.1 km²], Kelso has 0.71% of the county's total land area.
- Continue Reading ...
- When the Census Bureau conducts a census for a city like Kelso, they draw a boundary around the area in which they are going to conduct their count - this defines the sampling area (usually 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 population, area and housing for Kelso reflect the sampling area. Since the shape of the sampling area and the actual boundaries of Kelso might be different, it's best to check with the U.S. Census Bureau to resolve any difference between the two.
- 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 the center of the polygon, known as the centroid). At the time of the 2010 Census, the sampling area was located at:
- Lat: 46° 7' 38" (or 46.13°)
- Lon: -122° 52' 37" (or -122.88°)
- 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).
Housing Units ...
At the time of the 2010 Census, Kelso had 5,139 Housing Units<3> and with its population of 11,925 people, this averages 2.32 people per Housing Unit.
- Continue Reading ...
- The 2010 Census shows Kelso had a land area of 8.14 square miles [21.1 km²]. This translates to 604 Housing Units per square mile [233.5 housing units/km²].
- From the Census of 2000: Kelso had 5,067 Housing Units, a population of 11,895 people and a land area of 8.08 square miles [20.9 km²]. This gives a density of 2.35 people per Housing Unit and 605 Housing Units per square mile [233.8 housing units/km²].
- Note: Repeating the caution above (under Population Density), be aware that when comparing Housing Units between the 2010 and the 2000 Census, there were changes in the sampling area for Kelso and you need to be careful when comparing between the censuses. More information about these differences can be found in the section called Census-to-Census Observations ... (see below).
Cowlitz County ...
The city of Kelso is located in Cowlitz County<4> and is the County Seat for Cowlitz County.
The county had a population of 102,358 people at the 2010 Census. With it's population of 11,925 people, Kelso represented 11.65% of the county's total.
In addition, where the city of Kelso has a population density of 1,403 people per square mile [541 people/km²], Cowlitz County averages 89.8 people per square mile [34.66 people/km²].
For more information, please visit our Census Page for Cowlitz County.
Census-to-Census Observations ...
Introduction ...
When the Census Bureau takes a census count (or enumeration) for Kelso, 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 Kelso. It's important to note that from one Census to the next, the shape and location of the polygon can change.
- Continue Reading ...
- Although we don't have specific information about the shape of the polygon for Kelso or how it changed has over time, there is some information that can give us some hints. For example, since the shape of the sampling area is directly related to the shape of the polygon, any change to area probably indicates a new shape for the polygon.
- If you need precision or details about the methodology of the Census, you should visit the U.S. Census Bureau for a definitive answer.
Location ...
While generally coinciding with the GPS location (latitude/longitude) of Kelso, the latitude and longitude given by the Census Bureau actually indicates the GPS location of the polygon for Kelso.
- Continue Reading ...
- For the 2010 Census, the location was given as:
- Lat: 46.127435° (or 46°7'38" N)
- Lon: -122.877161° (or -122°52'37" W)
- For the 2000 Census, the location given was:
- Lat: 46.142033° (or 46°8'31" N)
- Lon: -122.906027° (or -122°54'21" W)
- The difference indicates that the U.S. Census Bureau moved the location of the polygon for the 2010 Census 9,028 feet to the southeast<5> 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 (#2410174) to Kelso. This identifier also marks a GPS point on the map, and that point lies within the boundaries of Kelso. The GNIS point has been mapped to the latitude/longitude:
- Lat: 46.124818° (or 46°7'29" N)
- Lon: -122.890800° (or -122°53'26" W)
- The GPS location given for the 2010 Census lies 3,575 feet to the east<6> of the point given by the GNIS for Kelso. For more information about this and the relationship of the various Federal Codes, please visit our Misc Page for Kelso.
Miscellaneous Information for Kelso ...
The Federal government has assigned various identifying codes to each community, county and state. At one time or another, the US Census Bureau has used one (or more) of the following identifiers when referring to either Cowlitz County or the city of Kelso:
- The GNIS Codes ...
- The FIPS Codes ...
- An earlier (and largely obsolete) identification method was called the Federal Information Processing Standard (FIPS):
- State Code: 53 (Washington)
- County Code: 015 (Cowlitz County)
- Place Code: 35065 (Kelso)
- State & County Code: 53/015 (Washington / Cowlitz County)
- State & Place Code: 53/35065 (Washington / Kelso)
- Misc. Census Codes ...
- Kelso 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 Kelso, it does identify addresses that are in (or near) Kelso. 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 Kelso:98626<7>
- 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 Kelso.
Off-the-Road Links ...
The official website for Kelso: www.kelso.gov/
The official website for Cowlitz County: www.co.cowlitz.wa.us/
The official website for State of Washington: https://wa.gov/
The official website of the U.S. Census Bureau
The official website of the U.S. Board on Geographic Names (BGN)
The official website of the U.S. Geological Survey (USGS)
Footnotes ...
| <1> | Every year, the US Census Bureau creates a population estimate for the preceeding year. Keep in mind that this value is an estimate and not an actual count. The most recent Census estimate is for the year 2019. |
| <2> | 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. |
| <3> | 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). |
| <4> | If you're interested in how the shape of Washington's counties, including Cowlitz, have changed over time, we recommend the Atlas of Historical County Boundaries. |
| <5> | The calculated bearing (or angle) to the 2010 Census location is 233 degrees and a distance of 9,028 feet. |
| <6> | The calculated bearing (or angle) to the GNIS point is 285 degrees and a distance of 3,575 feet. |
| <7> | When looking for a ZIP Code, whether Kelso or elsewhere, it's always best to check the website of the United States Postal Service (USPS). |