August 21 Meeting Outlines Redistricting Mapping Tools

For Immediate Release
August 09, 2021

August 21 Meeting Outlines Redistricting Mapping Tools

Informal meeting intended to introduce online tools for public proposals

San Rafael, CA – Those interested in how new 2020 U.S. Census data will impact the boundaries between Marin County’s five supervisorial districts are invited to an informal public workshop Saturday, August 21, that will be both online and in person. The hybrid workshop will take place from 10 a.m. to noon at the Marin County Board of Supervisors chamber, 3501 Civic Center Drive, Suite 330, San Rafael, CA, as well as stream live via Zoom.

Redistricting determines which neighborhoods are grouped together into a district for purposes of electing a supervisor. For the county government, redistricting means all five supervisorial districts need to have populations that are substantially equal in size. The process is required every 10 years upon release of new census figures to rebalance districts given changes in population. The current map based on the 2010 census is on the Marin County Board of Supervisors’ homepage.

The August 21 meeting is designed to introduce new online mapping tools for residents to propose their own supervisorial district maps and their own “communities of interest.”  Experts will provide information regarding the criteria to be used for redistricting and demonstrate the new online tools. The online mapping tool will be available on a new website,, beginning the week of August 16. Marin residents will be encouraged to submit maps of their own made with the interactive online tool that reflects population changes when a map boundary is moved on the screen. County staff desire to make the session as friendly and accessible as possible so residents feel comfortable asking questions and receiving “hands on” assistance.

Meeting hosts will cover the federal and state rules for redistricting, such as definitions of “communities of interest” that should be represented wholly on the revised map. Federal law prohibits racial gerrymandering, and state law requires that the boundaries must be contiguous, easily identifiable, and with minimal division of neighborhoods. After the presentation, participants will have the opportunity to engage with the mapping tool and ask questions about the tool’s functionality.

The County is planning at least four public hearings on redistricting starting in October when Census data will be available and will provide information in multiple languages. includes a calendar of events and details about the process, including how community members can become involved.

The federal government expects to release final census data in mid-August, and final state data are expected to be released in October. Counties must base redistricting criteria on those October numbers from the state.

By the end of the calendar year, the redistricting effort will result in a new supervisorial district map that shows relatively equal population distribution and compliance with both the Voting Rights Act and state requirements. The Board of Supervisors must adopt a final map by December 15 to ensure the new boundaries are reflected in the June 2022 primary elections.

Interested in the redistricting process? Sign up to receive periodic e-mailed updates from County staff under the topic “Marin Supervisorial Redistricting 2021” or check the California Secretary of State’s webpage on redistricting. Email the County staff with local questions about redistricting.



Anna Guiles
Strategic Projects Manager
County Administrator's Office

3501 Civic Center Drive
Suite 325
San Rafael, CA 94903
(415) 473-6361
Email: Anna Guiles
County Administrator website