Population forecast by the Population Research Center at Portland State University.
As of Wednesday, August 2, 2017
POLK COUNTY — The Population Research Center at Portland State University estimates that Polk County will grow at a yearly average of about 1.5 percent until 2035.
PSU released its population forecast on June 30, including estimates for countywide population and within cities’ urban growth boundaries. Urban growth boundaries include areas surrounding cities, but not yet within the city limits.
After evaluating those numbers, leaders in Dallas, Monmouth and Independence believe the forecasts are mostly accurate.
The forecast estimates population growth through 2035, and then from 2035 to 2067, and are used for planning purposes for cities.
“It allows us to do our longer-range planning. That is why they are so important,” said Jason Locke, Dallas’ community development director. “It was a good process and now we have these numbers and we can start moving forward with them over the next two years.”
Locke said initial forecasts sent by PSU seemed too conservative. PSU has average growth from 2017 to 2035 at 1.6 percent per year. Locke said Dallas made the case for faster growth during that period based on building trends in recent years.
“We have subdivisions being built and so forth,” he said. “We provided them with enough evidence to raise that to 1.8 percent.”
Dallas’ UGB population sits at 16,414 now. Forecasts have the 2035 population at 22, 665 with a growth rate of 1.8 percent between 2017 and 2035. In 2067, the forecast is 33,208 with 1.2 percent growth between 2035 and 2067.
Falls City’s UGB population within its urban growth boundary is at 1,003 now and forecasted to be 1,119 in 2035 and 1,285 in 2067. The average growth rates for the Falls City UGB are 0.6 percent (2017-2035) and 0.4 percent (2035-2067).
For Independence UGB, the current figure is 9,326. Its population forecasts are 13,803 in 2035, and 21,741 in 2067. Growth rates are 2.2 percent (2017-2035) and 1.4 percent (2035-2067).
In Monmouth UGB, the population is 9,994 now and is projected to be 12,943 in 2035 with a 1.5 percent growth rate between now and 2035, and 17,708 in 2067, with a 1 percent growth rate between 2035 and 2067.
Total for the county is 81,089 now, 105,217 in 2035, and 149,203 by 2067. Average growth rates are 1.5 percent (2017-2035) and 1.1 (2035-2067).
PSU will update its forecasts every three years.
Locke said the slow down after 2035 accounts for predicted slowing in-migration from other states and a lower birth rate. He said he’s confident in the final report numbers, as did Independence City Manager David Clyne and Monmouth City Manager Scott McClure.
“Overall if you look at methodology, look at the numbers that they used, we are pretty comfortable with that,” Locke said.
Locke added the long-term forecasts are different from the annual population estimates PSU puts out each year. Those estimates don’t add in population in the urban growth boundary and use different data, such as building and demolition permits issued by the cities.
In 2016, city population estimates (within city limits) are: Dallas — 15,345; Falls City — 950; Independence — 9,250; and Monmouth — 9,745.