Oregon is the First State to Adopt a 2020 Congressional Redistricting Plan, Here is How to View & Evaluate it in DistrictBuilder
Oregon became the first state to adopt a 2020 Congressional redistricting plan on September 27, 2021. With DistrictBuilder — a comprehensive tool for building redistricting maps using demographic and political data — you can view and evaluate the new map. Alongside a map in DistrictBuilder, we give you the tools to evaluate your districts with the metrics used to evaluate a plan as legal, valid, and fair.
In this post, we demonstrate how you can upload the newly adopted Oregon Congressional map and learn about its fairness using DistrictBuilder’s evaluation tools.
Block Equivalency Files: A Concise Format for Redistricting Plans
Redistricting plans are often communicated through a block equivalency file. In this format, each census block in a state (a census block is the smallest and most detailed geographical statistical area measured in the US Census) is given a label with its assigned district. This can be a congressional district, state legislative district, or local city council district. Take the following example from the top 5 lines from the block equivalency file from the Oregon Congressional Redistricting plan. The first column is the unique identifier for the geographic block assigned by the census (these are also commonly referred to as FIPS codes or GEOIDs, a useful guide to understanding the Census hierarchy is available here), and the second column refers to the legislative district the block is assigned to.
The block equivalency file for the Oregon Congressional redistricting plan can be found in the zip file available for download here and you can read more about Oregon redistricting at https://www.oregonlegislature.gov/redistricting.
Uploading the Oregon Block Equivalency File to DistrictBuilder
One option when you receive a block equivalency file for a redistricting plan and want to learn more about it is that you can import it into DistrictBuilder! When you are logged into your DistrictBuilder account on the My maps tab, you will see an Import button.
When you select Import, you can upload a block equivalency file and view it as a new map in DistrictBuilder. (Note: If your Block Equivalency Files is .txt file, resave it as a .csv before uploading) For example, Oregon became the first state to adopt a 2020 Congressional redistricting plan on September 27, 2021. The block equivalency file for the plan can be found in the zip file available for download here and you can read more about Oregon redistricting at https://www.oregonlegislature.gov/redistricting. Once you have the block equivalency file, Import it from the My maps tab in DistrictBuilder and fill out the following menu (for Districts select US House of Representatives).
After clicking Create Map, you can view, edit and evaluate the redistricting plan as a project in DistrictBuilder. Be sure to click Evaluate (upper right corner of the window) to see how the plan scores for equal population, contiguity, competitiveness, compactness, majority-minority districts, and other related statistics.
Evaluating a Redistricting Plan in DistrictBuilder
Alongside a map in DistrictBuilder, we give you the tools to evaluate your districts with the metrics used to evaluate a plan as legal, valid, and fair. The National Conference of State Legislatures has a guide to commonly accepted redistricting criteria, or what is known as traditional districting principles. We have built-in support for most of the criteria and continue to expand on this work with new features in the pipeline. For further information on how to evaluate a redistricting plan in DistrictBuilder and a detailed walk-through of the Evaluate panel, please move on to this guide:
