Colorado redistricting commissions identify sources of preliminary map data

The commissions charged with redrawing political maps in Colorado have determined what preliminary population data they will use in the unexpected temporary absence of definitive data from the U.S. Census Bureau.

In April, the commissions received apportionment data, which indicated that during the last decade the state’s population grew from 5,044,930 to 5,782,171 people. This means the state will gain a congressional seat, bringing its total number of seats in the U.S. House of Representatives to eight.

What the Census Bureau has yet to produce, however, is more granular information about the population, such as race, ethnicity, voting age, occupancy status and block-level details. The commissions need such information to redraw district boundaries for members of Congress and members of the Colorado House and Senate.

In the meantime, the commissions will use preliminary data from the Census Bureau’s American Community Survey and state population forecasts, along with distribution information from the bureau’s Master Address File, according to a press release from the commissions. The Master Address File “contains an accurate, up to date inventory of all known living quarters in the United States, Puerto Rico and associated island areas,” according the the Census Bureau.

Every 10 years, states have the opportunity to redraw political district maps. In 2018, Coloradans voted to implement two amendments — Y and Z — focused on reforming the way the state conducts legislative and congressional redistricting. The amendments created two independent 12-member commissions — one for congressional districts, one for state House and Senate districts — tasked with redrawing the maps in a way that focuses on fairness and minimizes the potential for gerrymandering. The amendments included stipulations that the commissions will not be able to fulfill, because they were based on a census timeline that was disrupted by the pandemic. State lawmakers are seeking a legislative workaround along with advance approval from the state Supreme Court.

Using preliminary data, commission staff expect to submit a congressional map to the Congressional Redistricting Commission by June 23 and state House and Senate maps to the Legislative Redistricting Commission by June 28. The commissions will conduct public hearings and review the maps until August, when the Census Bureau supplies official redistricting data. Final maps will be based on the official census data. 

Members of the public are encouraged to offer input throughout the redistricting process.