Supervisorial Redistricting Process

Following each decennial federal census, and using that census as a basis, the Board of Supervisors is required to adjust the boundaries of the supervisorial districts so that they are as nearly equal in population as is practical, in accordance with the applicable provisions of the federal Voting Rights Act. In establishing the boundaries of the districts, the Board must also consider the following factors: (a) topography, (b) geography, (c) cohesiveness, contiguity, integrity, and compactness of territory, and (d) community of interests of the districts. (Cal. Elec. Code Section 21500.)

The new Supervisorial Districts were created using United States Census Blocks and are legally described as such in the ordinance adopting them. Census blocks were not created using the County’s parcel layer. This may cause interpretation in certain areas to be difficult. Staff continues to make necessary adjustments in County systems and may make adjustments to this map as necessary to match the Census Block boundaries to the County’s data. This work is expected to take several months to complete. If after reviewing this map you still have questions regarding which Supervisorial District you reside in, please contact Information Technology, GIS Division at (209) 754-6608.

State redistricting information can be found here: