CO Code § 30-5-133 (2021)
2021 Colorado Code|Title 30 - Government - County|Article 5 - County Boundaries|§ 30-5-133. Jefferson

 Jefferson county is hereby bounded as follows:   Except for those portions that became part of the city and county of Broomfield on November 15, 2001, in accordance with sections 10 to 13 of article XX of the state constitution, commencing at a point where the township line between townships one and two south intersects the range line between ranges sixty-eight and sixty-nine; thence due west twenty miles; thence due south to the junction of North and South Clear creeks; thence south to the Platte river; thence down the center of said Platte river to the point where said river intersects the first correction line; thence west to the range line between ranges sixty-eight and sixty-nine; thence north to the place of beginning.   History. Source: G.L. § 364. G.S. § 439. L. 1889: P. 100, § 1. R.S. 08: § 1113. C.L. § 8594. CSA: C. 44, § 36. CRS 53: § 34-1-33 . C.R.S. 1963: § 34-1-33 . L. 2004: Entire section amended, p. 640, § 4, effective April 23.    Editor's note:   Pursuant to §§ 30-6-105 to 30-6-109 , inclusive, there is recorded in the office of the clerk and recorder of Park County in book 70, page 560, and in the office of the clerk and recorder of Jefferson County in book 140, page 400 (indexed in book 2 - Miscellaneous Papers - in the office of the secretary of state), a proclamation showing attachment to Park County and detachment from Jefferson County of territory described as follows:   “Beginning at the intersection of the boundary line between Park and Jefferson Counties with the center line of the South Platte River, about two miles above Lake George, thence down the said Platte River along its center line to intersection of said center line with the Second Correction Line South, thence westerly along said Correction Line to its intersection with the boundary line between Park and Jefferson Counties, thence along said boundary line to point of beginning.”   ANNOTATION   This section and § 30-5-153 are to be construed like patents or grants or segregations of a different date where the older in time necessarily concludes, and this principle requires first the determination of Jefferson county's boundaries and the inclusion therein of all territory which its lines would embrace, and the exclusion therefrom of all territory which would otherwise be embraced within the lines of Park county. Link v. Jones, 15 Colo. App. 281, 62 P. 339 (1900).   Wherever a line is run southerly or south, or due south, the result is precisely the same and the line thus stated in a description is to be taken as run due south unless there is some other thing in the description which compels or permits another course in order to work out the description which the grantor has put in a deed or whereby a general assembly has fixed the boundaries of a county. Link v. Jones, 15 Colo. App. 281, 62 P. 339 (1900).   Therefore, the description in the location of Jefferson county “thence south to the Platte river” starts and runs a line from the junction of North and South Clear creeks due south to the Platte river. Link v. Jones, 15 Colo. App. 281, 62 P. 339 (1900).   When the general assembly stated the western boundary of Jefferson county and ran the line south from the junction of North and South Clear creeks it ran a line due south making allowance for the magnetic variation, and it must strike the Platte river at the point where that line thus projected would strike the stream. Link v. Jones, 15 Colo. App. 281, 62 P. 339 (1900).