Title:
Title
Census Data for Redistricting, Public Mapping Tool and Submittal Process
End
FileID
File ID: 2021-00356
Location
Location: Citywide.
End
Recommendation:
Recommendation
Receive and file.
FileName
Contact: Rong Liu, GIS Program Manager, (916) 808-1979, Information Technology Department
Body
Presenter: Rong Liu, GIS Program Manager, and Carlos Porras, Senior GIS Specialist, Information Technology Department
Attachments:
1-Description/Analysis
Description/Analysis
Issue Detail: Every ten years, after the U.S. Census, the City of Sacramento must re-establish the boundaries for City Council districts. The resulting council district boundaries must be balanced in population in accordance with local, state, and federal rules governing the redistricting process.
At the February 10th Sacramento Independent Redistricting Commission (SIRC) meeting, city staff presented an overview of the redistricting criteria to provide SIRC and the public with a foundational understanding of the redistricting process. On April 14th, staff is presenting the Census data that will be used in redistricting and a high-level overview of the Redistricting Mapping Tool. A more in-depth demonstration of the tool will be presented once 2020 Census redistricting data has been released to states.
Census Data Characteristics:
The primary data source for redrawing council boundaries is the Public Law (PL) 94-171 dataset. The Census has delivered population and race summary statistics every ten years since 1975. The data collected from US households is summarized and protected by Title 13, which removes respondents’ personal information. This data is provided at block-level geography, which is the smallest level of geography available from the Census.
The data provided for redistricting is in six tables containing summary statistics on population and housing subjects, including total population by race and ethnicity, as well as voting age population (VAP) by race and ethnicity:
• H1. Occupancy Status (occupied, vacant)
• P1. Race
• P2. Hispanic or Latino, and Not Hispanic or Latino by Race
• P3. Race for the Population 18 Years and Over
• P4. Hispanic or Latino, and Not Hispanic or Latino by Race for the Population 18 Years and Over
• P5. Group Quarters Population by Major Group Quarters Type
Standard PL94-171 data tables used for redistricting are the following:
• Total Population
• Race:
o White (Non-Hispanic)
o Black or African American (Non-Hispanic)
o American Indian and Alaska Native (Non-Hispanic)
o Asian (Non-Hispanic)
o Native Hawaiian and Other Pacific Islander (Non-Hispanic)
o Some Other Race (Non-Hispanic)
o Two or More Race (Non-Hispanic)
• Ethnicity: Hispanic or Latino (of any race)
Redistricting Mapping Tool Demonstration:
To assist the community in developing and submitting redistricting plans, the City will provide, free to the public, online tools and resources. The online tools allow users to interactively redraw boundaries, share plans with others, create reports, and submit plans.
Tools & Resources
The redistricting webpage currently contains historical council district maps and historical population figures. There is also a resource page with links to various redistricting guides and informational publications.
The primary tool for users to develop a redistricting plan will be the internet-based City of Sacramento Redistricting Mapping Tool. This application was developed to be easily accessible and available to owners of both PC and Mac computers. This tool is an interactive and dynamic map containing city streets, neighborhoods, parks, and aerial photography, in addition to 2020 Census block-level data for population and race. The application allows users to choose from several selection tools to determine which Census blocks to assign to council districts. Navigation tools in the application allow users to zoom and pan within the council districts when choosing block data assignments.
Collaboration
The Redistricting Mapping Tool provides the means to participate in online groups and share versions of plans between group members. Users have the option to work individually or make their plans available to anyone with an active user account on the application. Plans that are shared with other users can be read-only, preserving the original work completed by the user. Users can also mark-up plans with comments and drawing features to help guide partners toward issues to review.
Reports
The Redistricting Mapping Tool is loaded with options to visually monitor changes to council districts. Users can choose from several tables and charts identifying the distribution of population and race/ethnicity within council districts. There are also preformatted reports available to display population, race/ethnicity, and deviation results for saved plans.
Plan Submissions
Plans developed using the Redistricting Mapping Tool can be submitted to SIRC using the online tool. Users are provided an opportunity to input relevant information regarding collaborators, plan objectives, and additional descriptive information. When the submitter has finished the plan submission process, the plan is then locked and formally submitted to the City. Individuals will receive an email confirmation of the submission. All submitted plans will be packaged and delivered on the City’s redistricting website to the public and commission after the submission date has closed.
Policy Considerations: The Sacramento Independent Redistricting Commission was formed in 2020 to establish city council district boundaries in a process that is free from special interests, politics, and political influence.
Economic Impacts: Not applicable.
Environmental Considerations: Not applicable.
Sustainability: Not applicable.
Commission/Committee Action: Not applicable.
Rationale for Recommendation: The SIRC has exclusive authority to redraw council district boundaries and must establish the process to accomplish this task in accordance with local, state, and federal rules governing the redistricting process.
Financial Considerations: Not applicable.
Local Business Enterprise (LBE): Not applicable.