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Policy: Spheres of Influence – Independent and Dependent Special Districts

In establishing spheres of influence for special districts, the Commission’s general policies are as follows:

  1. Parcels within a special district should be within the district’s sphere of influence. Include frontage roads within the sphere of influence.
  2. Creation of islands, i.e., territory to be served by the district which is outside of and not contiguous to main district boundaries and which may or may not be owned by the district, is generally contrary to Commission policy and shall be considered on a case-by-case basis.

Beyond these general policies, the Commission’s policies relating to sanitation districts and zones are as follows:

  1. Align a district/zone sphere of influence with its Urban Service Boundary (USB) as designated in the Sonoma County General Plan.
  2. When the existing district boundary or Urban Service Boundary creates “islands” or “saw-tooth boundaries,” the Commission will consider including adjacent areas to promote an orderly and logical sphere of influence.
  3. As a result of a voluntary combination (“merger” as defined in the Subdivision Map Act) of two parcels, one of which is within both the district and the Urban Service Boundary and the other is outside the district and the Urban Service Boundary, align the sphere with the boundary line of the original parcel that is in the district.
  4. As a result of a lot-line adjustment, in a situation where there are two parcels, one of which (Parcel A) is within the district and the Urban

Service Boundary and the other (Parcel B) is outside the district and the Urban Service Boundary, and a portion of Parcel B becomes part of Parcel A so that the Urban Service Boundary includes all of Parcel A and a portion of Parcel B, align the sphere with the original Parcel A, acknowledging that a portion of that parcel is not within the district or the sphere.

Legal Authority

The California Government Code §56425 states in part:

In order to carry out its purposes and responsibilities for planning and shaping the logical and orderly development and coordination of local governmental agencies so as to advantageously provide for the present and future needs of the county and its communities, the commission shall develop and determine the sphere of influence of each local governmental agency within the county and enact policies designed to promote the logical and orderly development of areas within the sphere.

State law precludes the Commission from approving proposals for a change of organization of territory outside an existing sphere of influence for an affected district. If the affected territory is outside the district’s sphere of influence, a proposal to LAFCO must include a request for an amendment to the sphere of influence. The joint sphere and change of organization review is to maintain consistency in district boundaries and its sphere for the provision of services as it relates to proposed annexation sites. 

Background and Discussion

Spheres of Influence are established by LAFCO to identify the probable physical boundaries and service areas of special districts. Spheres of influence are required to be updated every five (5) years and are amended as conditions warrant. The intent of this policy is to promote the efficient, effective, and equitable delivery of local and regional services for existing and future residents through spheres of influence and to encourage a collaborative process with agencies.

Generally, when establishing spheres of influence for special districts, the Commission includes within the sphere of influence only properties within the boundaries of the district. If an owner of a parcel outside district boundaries and sphere of influence wants that parcel to be in a district, he or she shall submit an application to LAFCO for sphere amendment and annexation, having previously received approval for annexation from the district’s board of directors.

The Commission acknowledges that, over the passage of many years, islands, as defined in the policy statement above, were created and allowed to receive services from various special districts. The Commission recognizes that these special districts are, or may be, as of the date of adoption of this policy, serving such territory and accepts these as exceptions to this policy. A listing of such districts and the island territory served is maintained in the LAFCO office. The Commission may consider exceptions to its general policy against creation of islands on a case-by-case basis and only when a proposed island is to be used for district purposes necessary for the operation of the district.

Exclusively for sanitation districts and zones, the County of Sonoma’s General Plan provides policy guidance, in the form of Urban Service Boundaries, to assist the Commission in considering adoption or amendment of spheres of influence for these districts/zones. The Urban Service Boundaries are the starting point for the Commission when reviewing a sphere of influence for a sanitation district or zone. Although a USB for a sanitation district or zone may be changed as part of a General Plan Update or General Plan Amendment, the district/zone’s sphere of influence cannot be changed until the Commission approves a proposal for a sphere amendment; this could, and likely would, be paired with a request for annexation to the district/zone.

In development of the policy to align spheres of influence for sanitation districts/zones with the Urban Service Boundary, the Commission is aware of situations in which the Urban Service Boundary splits a parcel, i.e., where only one section of the parcel receives services from a district, but the entire parcel is considered to be “in district.” In those situations, the Commission has determined that the sphere of influence shall be aligned with the Urban Service Boundary, thus limiting the potential for sprawl or premature development.

In cases of unique situations, the Commission may consider exceptions to the general policies.

Adopted Date: October 1, 2008
Amended Date: February 3, 2010