Slight population growth should prevent loss of Iowa congressional seat after 2020

The Iowa State Capitol building in Des Moines, photographed on Tuesday, June 10, 2014. (Liz Martin/The Gazette)
The Iowa State Capitol building in Des Moines, photographed on Tuesday, June 10, 2014. (Liz Martin/The Gazette)

CEDAR RAPIDS — Over the past year, Iowa grew by a Butler County.

According to the U.S. Census yearly population growth estimate released this week, Iowa’s population grew 0.5 percent, or 14,842 people — nearly equal to Butler County’s population.

It’s not much compared to Texas, which gained 400,000 residents between July 2016 and July 2017. However, it might be enough to prevent Iowa from losing a congressional seat in reapportionment following the 2020 census.

After each decennial Census Bureau count, seats in the U.S. House of Representatives are allocated to give each state one seat, with the remaining 385 seats allocated based on population.

Although the census numbers are good news for Iowa, Tim Hagle, associate professor of political science at University of Iowa, warns the state “may be in line to lose a seat following the 2030 census.”

“We had six congressional districts when I came here in 1988 and are down to four after three reapportionments,” Hagle said. “We’re growing, but just not as fast as several other states. If the trends continue, our slower growth won’t be enough to keep us above a single seat in the long term.”

Iowa has seen its congressional delegation shrink over the years from a high of 11 from the 1880s to 1930. Iowa’s population has been growing for 30 years, but other states have grown faster.

In 1910, both Iowa and California had 11 representatives in Congress. Today California has 53, but is in danger of losing one for the first time in its nearly 160-year history.


If Iowa loses a congressional seat after 2030, Hagle predicted it could be tricky to draw districts balancing the larger cities — several of which are in Eastern Iowa — with low-population rural areas.

For the most part, Iowa’s population growth has occurred in urban areas from in-migration, births and movement from rural Iowa, according to Census Bureau numbers.

“It’s possible that one or two of the districts could cover the state from river to river,” Hagle said. “That’s already something representatives in some other low-population states have to deal with, but not something we’re used to.”

Based on the new population numbers, Election Data Services projects that Iowa’s four congressional districts will average 786,428 people each. That would make Iowa’s congressional districts the seventh largest in the nation by population behind Montana, Delaware and South Dakota — each with one at-large seat — West Virginia, Idaho and Minnesota.

Election Data Services said that if the other 49 states stay the same, Iowa would have to gain 205,162 people — roughly 14 Butler counties — to add a congressional seat, or lose 550,520 people before losing a seat.

The new Census Bureau numbers indicate Colorado, Florida, North Carolina and Oregon will gain a seat in Congress. Texas could gain two, perhaps three, according to Election Data Services, which updated its projections based on this week’s census numbers.

Those gains come at the expense of New York, Michigan, Minnesota, Pennsylvania and West Virginia, each likely to lose one congressional district.

Election Data Services President Kimball Brace cautioned that the new data is very preliminary and subject to change. He has concerns about the 2020 census because of a lack of funding and changes in the counting process.


He also noted that major events, such as hurricanes and recessions, change population growth patterns.

“In a way, it would be sad for us to lose additional seats because we can be rightly proud of the nonpartisan way we handle redistricting,” Hagle said.

Rather than the Legislature drawing congressional district boundaries, which in many cases serves the political interest of the party in power, Iowa uses a nonpartisan commission to draw district lines.

“The fewer seats we have to redistrict at the federal level, the less it will matter that it’s a nonpartisan process,” Hagle said. “Three seats might still be interesting, but two seats likely won’t be, and at one, it no longer matters.”

l Comments: (319) 398-8375;

Give us feedback

We value your trust and work hard to provide fair, accurate coverage. If you have found an error or omission in our reporting, tell us here.

Or if you have a story idea we should look into? Tell us here.