Colorado § 31-12-104 - Eligibility for annexation.
Full text of Colorado Colorado Revised Statutes § 31-12-104 — Eligibility for annexation., with citation guidance and answers to common questions.
§ 31-12-104. Eligibility for annexation.
(1) No unincorporated area may be annexed to a municipality unless one of the conditions set forth in section 30 (1) of article II of the state constitution first has been met. An area is eligible for annexation if the provisions of section 30 of article II of the state constitution have been complied with and the governing body, at a hearing as provided in section 31-12-109, finds and determines:
(a) That not less than one-sixth of the perimeter of the area proposed to be annexed is contiguous with the annexing municipality. Contiguity shall not be affected by the existence of a platted street or alley, a public or private right-of-way, a public or private transportation right-of-way or area, public lands, whether owned by the state, the United States, or an agency thereof, except county-owned open space, or a lake, reservoir, stream, or other natural or artificial waterway between the annexing municipality and the land proposed to be annexed. Subject to the requirements imposed by section 31-12-105 (1)(e), contiguity may be established by the annexation of one or more parcels in a series, which annexations may be completed simultaneously and considered together for the purposes of the public hearing required by sections 31-12-108 and 31-12-109 and the annexation impact report required by section 31-12-108.5.
(b) That a community of interest exists between the area proposed to be annexed and the annexing municipality; that said area is urban or will be urbanized in the near future; and that said area is integrated with or is capable of being integrated with the annexing municipality. The fact that the area proposed to be annexed has the contiguity with the annexing municipality required by paragraph (a) of this subsection (1) shall be a basis for a finding of compliance with these requirements unless the governing body, upon the basis of competent evidence presented at the hearing provided for in section 31-12-109, finds that at least two of the following are shown to exist:
(I) Less than fifty percent of the adult residents of the area proposed to be annexed make use of part or all of the following types of facilities of the annexing municipality: Recreational, civic, social, religious, industrial, or commercial; and less than twenty-five percent of said area's adult residents are employed in the annexing municipality. If there are no adult residents at the time of the hearing, this standard shall not apply.
(II) One-half or more of the land in the area proposed to be annexed (including streets) is agricultural, and the landowners of such agricultural land, under oath, express an intention to devote the land to such agricultural use for a period of not less than five years.
(III) It is not physically practicable to extend to the area proposed to be annexed those urban services which the annexing municipality provides in common to all of its citizens on the same terms and conditions as such services are made available to such citizens. This standard shall not apply to the extent that any portion of an area proposed to be annexed is provided or will within the reasonably near future be provided with any service by or through a quasi-municipal corporation.
(2) (a) The contiguity required by paragraph (a) of subsection (1) of this section may not be established by use of any boundary of an area which was previously annexed to the annexing municipality if the area, at the time of its annexation, was not contiguous at any point with the boundary of the annexing municipality, was not otherwise in compliance with paragraph (a) of subsection (1) of this section, and was located more than three miles from the nearest boundary of the annexing municipality, nor may such contiguity be established by use of any boundary of territory which is subsequently annexed directly to, or which is indirectly connected through subsequent annexations to, such an area.
(b) Because the creation or expansion of disconnected municipal satellites, which are sought to be prohibited by this subsection (2), violates both the purposes of this article as expressed in section 31-12-102 and the limitations of this article, any annexation which uses any boundary in violation of this subsection (2) may be declared by a court of competent jurisdiction to be void ab initio in addition to other remedies which may be provided. The provisions of section 31-12-116 (2) and (4) and section 31-12-117 shall not apply to such an annexation. Judicial review of such an annexation may be sought by any municipality having a plan in place pursuant to section 31-12-105 (1)(e) directly affected by such annexation, in addition to those described in section 31-12-116 (1). Such review may be, but need not be, instituted prior to the effective date of the annexing ordinance and may include injunctive relief. Such review shall be brought no later than sixty days after the effective date of the annexing ordinance or shall forever be barred.
(c) Contiguity is hereby declared to be a fundamental element in any annexation, and this subsection (2) shall not in any way be construed as having the effect of legitimizing in any way any noncontiguous annexation.
Source: L. 75: Entire title R&RE, p. 1078, § 1, effective July 1. L. 87: (1)(a) amended, p. 1218, § 1, effective May 28. L. 91: (2) added, p. 763, § 1, effective May 15. L. 2010: IP(1) amended, (HB 10-1259), ch. 211, p. 914, § 3, effective August 11.
Editor's note: This section is similar to former § 31-8-104 as it existed prior to 1975.
Cross references: For annexation of unincorporated areas, see § 30 of article II of the state constitution.
ANNOTATION
Annotator's note. Since § 31-12-104 is similar to former § 31-8-104 prior to the 1975 repeal and reenactment of this title, and laws antecedent thereto, relevant cases construing those provisions have been included in the annotations to this section.
The annexation statutes are more than mere formalities. Johnston v. City Council, 189 Colo. 345, 540 P.2d 1081 (1975).
Contiguity required. Territory is eligible for annexation if a percentage of its boundaries are contiguous with those of a city. City of Littleton v. Wagenblast, 139 Colo. 346, 338 P.2d 1025 (1959).
Specific findings required for proposed area for annexation. In a unilateral annexation pursuant to § 31-12-106 (2), the legislative body with annexing authority must make specific findings at a hearing that the proposed area to be annexed has had the requisite boundary contiguity for the requisite period of time before such an area is eligible for annexation by the governing body. Cesario v. City of Colo. Springs, 200 Colo. 459, 616 P.2d 113 (1980).
A resolution of the absolute factual existence of the one-sixth contiguity requirement is mandatory. Johnston v. City Council, 177 Colo. 223, 493 P.2d 651 (1972).
The size and shape of a parcel to be annexed is immaterial and is conclusively a legislative problem. Bd. of County Comm'rs v. City & County of Denver, 37 Colo. App. 395, 548 P.2d 922 (1976).
But courts will not read into the annexation statutes limitations relating to unusual or irregular shapes or patterns of territory annexed. Bd. of County Comm'rs v. City & County of Denver, 37 Colo. App. 395, 548 P.2d 922 (1976).
City's division of property into multiple one-foot strips of land to satisfy the one-sixth contiguity requirement is not prohibited. Arapahoe County Bd. of County Comm'rs v. City of Greenwood Vill., 30 P.3d 846 (Colo. App. 2001).
Where the property annexed includes public streets, the court may include the perimeter of the streets in calculating whether one-sixth of the perimeter of the annexed property is contiguous to the annexing municipality. The one-sixth requirement is in no way altered by § 31-12-105 (1)(e). Bd. of County Comm'rs v. City of Lakewood, 813 P.2d 793 (Colo. App. 1991).
It is not permissible to include and use a county street as the "pole" in order to meet the subsection (1) contiguity requirement, but to ignore the county ownership of the street for purposes of meeting the § 31-8-106(3) sole ownership requirement in a city annexation ordinance. Bd. of County Comm'rs v. City & County of Denver, 190 Colo. 8, 543 P.2d 521 (1975).
But a public way or a portion of a public way can be utilized as a noncontiguous boundary of the annexed territory, since the statute contains no such restriction. Bd. of County Comm'rs v. City & County of Denver, 37 Colo. App. 395, 548 P.2d 922 (1976).
Legal description held to be in substantial compliance with the requirements of this section. Slack v. City of Colo. Springs, 655 P.2d 376 (Colo. 1982).
Effect of ditch. The statutory requirement of contiguity is satisfied where part of the area to be annexed is bounded by a ditch, the east side of which is contiguous to the city. Rice v. City of Englewood, 147 Colo. 33, 362 P.2d 557 (1961).
Contiguity basis for finding of community of interest. With respect to the matters of community of interest, that the territory is urban or will be urbanized in the near future, and that the territory is integrated or capable of being integrated into the city, subsection (1)(a) provides that the fact that the territory has the contiguity with the annexing municipality required by this article shall be a basis for a finding of compliance, and where there was a requisite continuity, the court erred in its criticism of the findings of the city council. Breternitz v. City of Arvada, 174 Colo. 56, 482 P.2d 955 (1971).
Once the one-sixth contiguity requirement is satisfied, the community of interest requirement is also satisfied. Arapahoe County Bd. of County Comm'rs v. City of Greenwood Vill., 30 P.3d 846 (Colo. App. 2001).
Contiguity requirement not met where federal land intervened between town and the proposed annexation and consent was not obtained from federal agency to divide that tract from the rest of the federal lands. Caroselli v. Town of Vail, 706 P.2d 1 (Colo. App. 1985).
Subsection (1)(a) is not ambiguous; therefore the court will not consider the legislative history of the section to aid in construction. Bd. of County Comm'rs v. City of Lakewood, 813 P.2d 793 (Colo. App. 1991).
Municipality lacked standing to contest annexation because it did not have a plan in place for the area annexed. Town of Berthoud v. Town of Johnstown, 983 P.2d 174 (Colo. 1999).
While the county is authorized to own, dispose of, and designate the uses of real property, it has no authority to define terms employed by the general assembly in state statutes. Rather, interpretation of subsection (1) is a question of law for the courts to decide, and judicial review is therefore de novo. Accordingly, in determining whether the roadways at issue are open space for purposes of subsection (1)(a), the county's designation is not binding. Bd. of County Comm'rs v. City of Aurora, 62 P.3d 1049 (Colo. App. 2002).
Property at issue designated by the county has been improved through grading and surfacing and serves as public roadways. A parcel consisting entirely of roadway is not "essentially unimproved" and, therefore, is not open space within the meaning of subsection (1)(a). Because the county roads here are not open space, they do not affect contiguity under the terms of this section. Hence, the court erred in voiding the annexation of the two parcels for failure to satisfy the contiguity requirement. Bd. of County Comm'rs v. City of Aurora, 62 P.3d 1049 (Colo. App. 2002).
Municipal annexation of property does not automatically remove property from all other political subdivisions. Municipal annexation of property detaches the property from the unincorporated portion of a county but does not automatically remove the property from other political subdivisions, particularly where other statutory provisions govern such removal. Municipal annexation of property within the boundaries of a regional transportation authority therefore does not remove the property from the authority and the authority may continue to levy its sales tax on taxable transactions conducted on the property. Wal-Mart Stores v. Pikes Peak Rural Transp., 2018 COA 73, 434 P.3d 725.
Source: official Colorado text · Last verified 2026-08-27
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