The U.S. Census has released more detailed data about Iowa’s population, showing growth in three of the state’s five largest cities. 

Iowa’s five most-populous cities rank in this order: Des Moines, Cedar Rapids, Davenport, Sioux City and Waterloo.  According to the U.S. Census Bureau, the population of Des Moines grew 2.4 percent in the past decade. Despite the flood which struck in 2008, the population of Cedar Rapids in 2010 was still 4.6 percent higher than it was in 2000. 

Davenport’s population grew by 1.3 percent.  Sioux City’s population fell by 2.7 percent over the past decade, while Waterloo’s decreased 0.5 percent.

The Census data indicates the suburbs around Iowa’s largest cities are growing substantially.

Polk County — home to the capitol city of Des Moines — is Iowa’s largest county and, according to the Census Bureau, its population jumped 15 percent in the past decade.  The Cedar Rapids/Marion metro is situated in Linn County, which saw a more than 10 percent increase in its county population over the decade. 

Dallas County home to the fast-growing western Des Moines suburbs of Waukee and West Des Moines, saw its population grow by 62 percent in the past decade.

Iowa’s governor sees both good and bad news in the numbers. “The governor is happy to see that Iowa’s population grew, but the loss of a congressional district should concern all Iowans. Iowa’s population did not grow nearly fast enough, and this data shows the need for Gov. Branstad’s ambitious plan to create 200,000 jobs over the next five years,” Tim Albrecht, a spokesman for Governor Branstad, said in a written statement. “The governor believes we must expand opportunities for all Iowans, and unleash our vast potential for job creation in order to accelerate our population growth.”

The release of the U.S. Census Bureau’s detailed information about Iowa’s population sets in motion a process at the statehouse which will redraw state legislative and congressional district lines. Iowa’s population has shifted, so there will be fewer state legislators representing rural areas, and more from the suburbs. 

“Clearly the areas surrounding some of the larger cities have grown substantially so maybe there’ll be some more suburban districts and then, of course, we’re going to four congressmen,” House Speaker Kraig Paulsen (R-Hiawatha) says. “I don’t even have the slightest idea what those four districts look like.” 

Iowa currently has five congressional districts and while the state’s population grew over the past decade, states in the south and west grew faster, so Iowa is losing a seat in the U.S. House.  With the Census details about Iowa’s population, the Legislative Services Agency now draws up a redistricting plan and Senate Democratic Leader Mike Gronstal of Council Bluffs says it’s a “unique-to-Iowa” process. 

“In a non-partisan basis, not in a bipartisan basis, a non-partisan basis they will draw the boundaries,” Gronstal says. “…Since we’re getting the information today, we’ll probably see their results by the end of March.” 

Legislators must either accept or reject that first redistriction plan; they cannot jigger the district lines.  If the House and Senate reject the plan, the Legislative Services Agency draws a second map of legislative and congressional dsitricts.  If the legislature fails to endorse a plan by fall, the justices of the Iowa Supreme Court will draw up the new district lines.

Gronstal says when the Census data is first released, it sort of “sucks the oxygen out of the room” — as legislators contemplate being forced into a contest against another incumbent because of the way population has shifted and district lines are redrawn.

(This story updated at 7:38 p.m. with more details from teh Census Bureau.)

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