Analyzing Washington’s Adjusted Redistricting Data

Overview

Washington uses adjusted (or modified) data for US congressional, state legislative, and state congressional redistricting.

• 7,705,281 total population in the original PL file
• 7,705,281 total population in the adjusted PL file
• 0 total population difference between the two

Even in states where the total population is unchanged, the distribution of population within the state can be affected.

To give you a sense for how these population shifts affect Washington’s redistricting, the average district sizes in Washington are:

• 157,250 people per state House district
• 157,250 people per state Senate district
• 770,528 people per Congressional district

The dataset used to create this report is the official redistricting dataset.

County Level Analysis

See the appendix for a detailed breakdown of county level population changes.

Block Level Analysis

In general, the changes in block population are not uniform: most blocks are unaffected by modification, while a handful of blocks lose a large amount of population that goes to a larger number of blocks in smaller quantities.

• 158,093 census blocks in Washington
• 148,350 census blocks have the same population following modification
• 9,702 census blocks gained population following modification
• 41 census blocks lost population following modification (Of the 41 census blocks that lost population following reallocation, 27 contained facilities according to our analysis conducted with PPI data.)
• 1 census block has a negative population following modification.

Official Language

The official language for Washington’s adjustment is:

The redistricting commission shall: (a) Deem each inmate incarcerated in a state adult correctional facility and person residing or placed in a juvenile justice facility or committed to receive involuntary behavioral health treatment under chapter 71.05 RCW as residing at his or her last known place of residence, rather than at the institution of his or her incarceration, residence, or placement… (c) Deem an inmate or resident in state custody in Washington whose last known place of residence is outside of Washington or whose last known place of residence cannot be determined to reside at the location of the facility in which the inmate or resident is incarcerated, placed, or committed; and (d) Adjust race and ethnicity data in districts, wards, and precincts in a manner that reflects the inclusion of inmates and residents in the population count of the district, ward, or precinct of their last known place of residence. [S]