Get Involved
Draw A Map
Redistricting is different than most issues that come before the Board. Instead of being limited to saying you support or oppose a County prepared map, you can draw a map yourself!
El Dorado County does not provide a tool for the public to use to develop redistricting alternatives. However, it does provide a means to download the files needed to develop redistricting alternatives. These files can be downloaded from the GIS Redistricting Hub to access and download data and the census files, and submit your own maps for consideration. The census data file is
Blocks2020PopAndHU. This file has both geometry and population, but it does not have data such as age, race, ethnicity, etc. Those data attributes can be downloaded from the US Census Bureau.
The County will accept GIS ready files, spreadsheets, and even hand-drawn proposals. The minimum standards for each of those are described below. All submissions must include a contact name and contact information such as an email or phone number. And please indicate whether or not your contact information can be made public.
Submissions can be sent electronically to
redistricting@edcgov.us . Paper submissions can be dropped off at, or mailed to:
GIS Redistricting
360 Fair Lane, Bldg B
Placerville, CA 95667
The deadline for GIS-Ready and spreadsheet submissions is
October 22, 2021. Hand-drawn submissions are due
October 15, 2021.
To provide feedback on County-prepared map alternatives, you can visit the Draft Maps webpage.
GIS-Ready Files
The following file types are acceptable: Esri shapefile or GDB; KML/KMZ; or GeoJSON. The projection or coordinate reference system must be provided, WGS84 is preferred. The geometry type must be polygon or polyline.
If the submission is only district outlines, each district must include the following attributes/properties:
Assigned_Population β the total population assigned to this district.
District_Id β an identifier specifying which district this boundary represents.
If the submission is at the census tract block level, each block outline must have the following attributes or properties:
GEOID20 - this is the US Census Bureau's identifier for the block.
Tot_Pop - this is the total population assigned by the US Census Bureau to this block.
District_Id - an identifier specifying the district assigned to this block and population.
Block level submissions will be dissolved by District_Id and the populations summarized by Tot_Pop. This will result in district level boundary outlines.
GIS Ready file submissions will be tested for completeness and usability. The population summaries for each district and/or block will be reviewed. Incomplete or invalid census attributes will be cause for dismissal of the submission. Files that cannot be readily projected will also be dismissed.
Files that pass the GIS review will be added to the Public Comment app and will be part of the public review process.
Spreadsheets
Acceptable spreadsheet formats are CSV, Microsoft Excel, or Google Sheets. Each row must contain:
GEOID20 - this is the US Census Bureau's identifier for the block.
Tot_Pop - this is the total population assigned by the US Census Bureau to this block.
District_Id - an identifier specifying the district assigned to this block and population.
Spreadsheet submissions will use theGEOID20 column to join to the census geometry. This geometry will be dissolved by District_Id and the populations summarized by Tot_Pop. Submissions that do not join or are incomplete or contain invalid attributes will be dismissed.
Hand-Drawn Submissions
Hand-drawn submissions must be drawn using census tract blocks as the boundary outlines for each district. All blocks that form an interior district boundary must be identified. This can be done by noting the GEOID20 on the map. Or by including a list that cross-references boundary GEOID20 ids and their assigned District_Id.
Free Applications for Building Map Alternatives
- https://davesredistricting.org/maps#home
- https://www.districtbuilder.org/
- Districting for ArcGIS β A free extension for Esri ArcMap (Must already have purchased an ArcMap license.)
- QGIS
Communities of Interest
Our primary goal when redrawing districts is to draw lines that respect neighborhoods, history and geographical elements.
Publicly-submitted Communities of Interest have been incorporated into our mapping tools and can be viewed by visiting the Community of Interest Application site.