Third in a series.
The dam broke just after the 1990 census.
West Des Moines had a small spot in Dallas County right before that — a portion tucked south of University Avenue that included the Des Moines Golf and Country Club — but there was very little going on north and west of I-35/80. That was soon going to change, big time.
In 1990, Waukee went forward with plans to annex land along University Avenue up to the Polk County line, and Clive, afraid of being boxed in, countered with annexation plans of its own. When combined with a state law change regarding annexations taking effect during this period, a lawsuit resulted that wasn’t settled until 1994. According to an appendix to the federal 1992 Economic Census, Urbandale and Grimes also annexed into Dallas County in May 1990 and April 1991, respectively. The land rush was on. Walnut and Boone townships have been having their rural portions squeezed slowly, and not so slowly, out of them since, as that area became THE hottest growth spot in Iowa.
Source note repeated: The following statistics come from the Census Bureau’s final yearly intradecade percentage growth estimates for the 1990s and 2000s, and the 2017 data used for the 2010s. All years are fiscal (starting July 1 of the preceding calendar year).
Dallas County started the 1990s with 29,755 people. In 1991 it posted a 2.77% gain; only 18 other counties had growth estimated above 1%. Two years later, Louisa County barely had a bigger percentage gain. After that, though, from 1994 through 2017, Dallas County’s growth has reigned supreme in Iowa, and often second place isn’t even close. (Since 2001, second place has been Johnson eight times, Story four, Warren three, Buena Vista one, Calhoun one.) Dallas, Johnson, Linn, Polk, and Warren haven’t had a down year in that entire span.
Dallas County’s growth is so astronomical compared to others that it’s casting a greater shadow over the state as a whole. In every population estimate since 1988, Iowa has never lost people. But since 1993, the yearly percentage increase has passed 0.6% only once, 2006 (0.61%). If you take Dallas County out of the equation entirely, in the 1990s the state growth rate was lower by about 0.03% per year. In the 2010s so far, the rate of growth for the other 98 counties combined is 0.08% to 0.11% less per year.
Yesterday I noted Cherokee County has lost 2700 people, or nearly 20 percent, since 1990. Well, Dallas County added 2700 people in fiscal 2014 alone — to a total population more than six times Cherokee’s. Since 2010, a population equivalent to that of Winneshiek County has moved there.
With the most recent estimates, Dallas County has slightly more people (87,235) than Adair, Adams, Union, Clarke, Lucas, Monroe, Taylor, Ringgold, Decatur, Wayne, and Appanoose counties combined (86,933). Dallas County has about as many people as Cherokee, O’Brien, Clay, Buena Vista, Ida, Sac, and Calhoun counties combined (87,825). And so on.
Dallas County as a whole has added two-thirds of a state House seat, with two more years of estimates ahead of the 2020 census. (Of course, Perry is also a factor, not just the suburbs, lest I be accused of omission through ignorance.) No wonder a seat there is so attractive to Chris Hagenow.
Assists for this blog post come from two ISU Community and Regional Planning master’s theses: “Annexation in Iowa: an analysis of the Iowa annexation statutes” by Robin Renae Habeger, 1997, and “Using the Land Evaluation and Site Assessment (LESA) technique in the rural-urban fringe: A case study of Dallas County, Iowa,” by Brian Ray Schoon, 1991.