U.S. Census Bureau

boundary changes

Geographic Change Notes: Colorado

State: Colorado   (08 CO)
All legal boundaries of governmental units are as reported through the Census Bureau’s 2003 Boundary and Annexation Survey, unless otherwise noted.
Area Effective Date Change
Adams County 11/15/01 area partially reduced by formation of Broomfield County
Arriba town 01/01/00 Census place code change, from 0030 to 0035
Bennett town 06/22/99 annexation into Arapahoe County
Berthoud town 12/24/96 annexation into Weld County
Black Hawk city 01/01/90 area description change, from town to city
Bonanza town 01/01/90 name change, from Bonanza City town to Bonanza town; FIPS place code change, from 07575 to 07571
Boulder County 11/15/01 area partially reduced by formation of Broomfield County
Brighton city 03/15/91 annexation into Weld County
Broomfield County 11/15/01 new county (FIPS code 014) organized from parts of four counties: Adams, Boulder, Jefferson, and Weld; coextensive with Broomfield city
Carbondale town 01/01/90 FIPS change, from 12030 to 12045
Castle Rock town 01/01/90 area description change, from city to town
Centennial city, Arapahoe County 02/07/01 new incorporation (FIPS: 12815)
Foxfield town, Arapahoe County 12/13/94 incorporation (Census place: 0483; FIPS: 28105)
Jefferson County 11/15/01 area partially reduced by formation of Broomfield County
Johnstown town 06/07/99 annexation into Larimer County (Census place code: 0690; FIPS code: 39855)
Keota town 02/19/91 disincorporation
Littleton city 12/27/90 annexation into Jefferson County
Lone Tree city, Douglas County 12/29/96 incorporation (Census place: 0817; FIPS: 45955)
Longmont city 05/25/90 annexation into Weld County
Mountain Village town, San Miguel County 03/10/95 incorporation (Census place: 0926; FIPS: 52550)
Prospect Heights town 06/14/94 disincorporation
South Fork town, Rio Grande County 05/01/92 incorporation (Census place: 1237; FIPS: 72395)
Thornton city 04/15/91 annexation into Weld County
Weld County 11/15/01 area partially reduced by formation of Broomfield County
Windsor town 11/14/94 annexation into Larimer County