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Policy: Unincorporated Islands

The Commission shall require annexation of all parcels within an unincorporated island for islands meeting the following criteria:

  1. The island is comprised of fewer than 150 acres;
  2. The island is completely surrounded by the city;
  3. Fewer than 12 registered voters reside within the entire island;
  4. The proposal is exempt under California Environmental Quality Act Guidelines Section 15319 (existing public or private structures are developed to the density allowed by the current zoning or pre-zoning of either the city or county, whichever is more restrictive), as determined by the lead agency.
  5. The numbers of owners of land who own more than 50 percent of the total assessed value of land within the island have consented to annexation or the combination of those owners and the owners of properties that have annexation covenants represents a majority of properties within the island.

Application for annexation of territory encompassing less than an entire island may be considered if the above criteria are not met.

Cities are encouraged to annex substantially surrounded fringe islands. The Commission defines “substantially surrounded” as territory contiguous to the annexing city on at least 75 percent of its boundaries.

The Commission encourages cities to use the island annexation provisions of the Cortese-Knox-Hertzberg Local Government Reorganization Act of 2000 (GC §56375.3).

The Commission discourages annexation of territory to a city if that annexation splits an island of unincorporated territory, creating additional islands. Special circumstances may exist, and islands may be created if the Commission finds that:

  1. Application of the restriction against creating islands would be detrimental to the orderly development of the community, and
  2. The area that would be enclosed as an island is so located that it cannot reasonably be annexed to another city or incorporated as a new city

Legal Authority

The Legislature provided each LAFCO with the authority to “establish written policies and procedures and exercise its powers...in a manner consistent with those policies and procedures and that encourages and provides planned, well-ordered, efficient urban development patterns with appropriate consideration of preserving open-space and agricultural lands within those patterns.” (Government Code Section §56300) This policy implements the intended goal of well-ordered growth.

Further, the Cortese-Knox-Hertzberg Act addresses island annexations and the creation of islands as follows:

  • Prohibits the creation of islands of unincorporated territory via annexation, unless the Commission determines otherwise.
  • Waives the prohibition if the Commission can find that such restriction would be detrimental to the orderly development of the community and that the area to be included within the annexation boundary is located such that it could not be reasonably annexed to another city or incorporated as a new city.
  • Assists cities and LAFCO in significantly streamlining the procedural requirements for island annexations that meet specific criteria. Upon a city’s use of this section of state law, the Commission must approve annexation of an island, after notice and hearing and must waive protest proceedings. The waiver of protest proceedings is scheduled to sunset as of January 2014, unless extended through state legislation.

The statute does not define “substantially surrounded.” In its previously-adopted Commission Membership, Meetings and Budget Policies, the Commission has defined this term a ‘territory contiguous to the annexing city on at least 75 percent of its boundaries.”

Background and Discussion

Recognizing that cities are the logical service providers for municipal-level services and that unincorporated islands can be more effectively and efficiently served by the cities that surround them, Sonoma LAFCO is committed to eliminate all existing unincorporated islands that are completely surrounded by a city. This goal aligns with that of the Sonoma County General Plan, which advocates locating “future growth within the cities and unincorporated service areas in a compact manner using vacant “infill” parcels and lands next to existing development at the edge of these areas.”

Providing efficient public services is hindered when numerous unincorporated islands are scattered throughout cities. It has been demonstrated that service providers have difficulty determining jurisdictional boundaries when routing or responding to calls for service. Reducing the size of a small island of less than five parcels, as an example, to two or three parcels makes identification even more difficult. The Commission desires that the small islands be annexed at one time.

By restricting the policy to islands that are “uninhabited” - defined in state law as territory in which fewer than 12 registered voters reside, the Commission eliminates the potential for the additional costs and effects of an election. Owners of land within an island would still have the potential to stop an annexation through a majority protest, but the likelihood of success of an annexation proposal is much higher with smaller islands.

The Commission’s staff works closely with the cities in Sonoma County in determining boundaries for each annexation proposal. Prior to submittal of an application of less than an entire island, the affected city should provide the Commission’s staff with a summary of an annexation sentiment survey. The Commission’s staff will work with each city by attending community meetings, preparing annexation information, and responding to inquiries by phone, e-mail, or in individual meetings.

Areas that are adjacent to many cities and are partially surrounded by the cities are referred to as “fringe islands.” These fringe islands have numerous shapes and individual characteristics. The Commission understands that annexation of these areas may be an incremental process. Islands on the fringe of cities do not have to be completely pre-zoned and annexed in a single action.

State law prohibits creation of islands through a proposal for annexation. Although the law allows waiver of such restriction if the Commission can make specific findings, the Commission strongly discourages annexation boundaries that would create one or more islands and, unless persuaded otherwise, would deny such a proposal.

In situations in which additional public services, such as connection to city sewer and/or water systems, for an entire unincorporated island are desired, the Commission advocates that such service(s) be extended through annexation of the affected territory to the city which would provide the service(s). However, the Commission is aware that emergency situations can arise and/or a city may not be prepared to annex large areas of territory. In those situations, the Commission may be willing to consider extensions of service via Outside Service Area Authorizations. In such instances, the Commission’s policy on Extensions of Service Within a City’s Sphere of Influence would apply.

Adopted: October 10, 2012