Policy: Spheres of Influence - Cities

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

1. Include all properties within the incorporated city.
2. Include properties wholly within both the voter-approved Urban Growth Boundary and the Urban Service Boundary for the city in the Sonoma County General Plan. Include frontage roads.
3. Include properties within a city’s Urban Growth Boundary that are outside the Urban Service Boundary for the city in the Sonoma County General Plan.
4. Exclude parcels outside the Urban Growth Boundary and Urban Service Boundary of a city.

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 city. If the affected territory is outside the city’s sphere of influence, a proposal to LAFCO for annexation must include a request for amendment to the sphere of influence. The joint sphere and change of organization review is to maintain consistency in city boundaries and its sphere for the provision of services as it relates to proposed annexation sites.

Spheres of influence are established by LAFCO to identify the probable physical boundaries and service areas of cities. Spheres of influence must be updated every five (5) years and are amended as conditions warrant. The intent of this policy is to promote he 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.

By 2008, the Commission confirmed existing spheres of influence for all nine cities in the county. The spheres of influence and Urban Growth Boundaries for the eight cities in the County where voters have approved them often coincide, and, for most cities, the Urban Service Boundary, as designated in the Sonoma County General Plan, is frequently the same “line.” However, because of the Board of Supervisors’ approval of the 2020 General Plan in September 2008, there are a number of instances in which these three lines are not coterminous, i.e., where a city’s sphere of influence differs from its Urban Growth Boundary and Urban Service Boundary, which are generally coterminous. In those cases, besides reviewing the general policy, the Commission, must evaluate any changes to the sphere of influence using the following criteria:

1. Relationship to city boundary, streets, open space
2. Existing uses
3. Size & development potential of parcel
4. Topographical & physical considerations
5. City’s willingness to serve
6. City’s ability to serve
7. Planning principles
8. Legal agreements and settlements

Adopted: February 3, 2010