Population Growth in Benton & Franklin Counties Surpasses State and National Rates

By Dr. Kelley Cullen

Economists typically purport that moderate increases in population are positively associated with economic growth, primarily through a larger workforce and increased consumption benefits. However, a burgeoning population can also lead to concerns over traffic, the environment and essential services such as education. Therefore, it is important for a community to monitor population growth.

Benton Franklin Trends indicator 0.1.1 Total Population & Annual Growth uses data from the Washington State Office of Financial Management which estimates the total population and the annual growth rates of Benton & Franklin Counties, both individually and combined. The Cities of Kennewick, Pasco, and Richland along with Washington State and the U.S. are also available.  

To local residents of the greater Tri Cities area, it probably comes as no surprise that the postcensal estimates from the US Census Bureau show that Franklin County experienced that fastest rate of population growth for any county in Washington over the past decade. Further, Benton County had the fourth highest rate of county population growth. In fact, only six of Washington’s counties experienced rates of population increases above the state average cumulative rate of growth (15%), with both Franklin (22%) and Benton (17.7%) among them as shown in Table 1.

 Table 1. Change in Population, Top Ten Counties & State, 2011-2021

Source:  Washington State Office of Financial Management

What might be more surprising is that these higher rates of population are expected to continue for the current decade, through 2030. According to the Washington State OFM, which prepares projections of population by county as well as for the state overall, Franklin County should continue to lead the state in population growth rate, with Benton County not far behind. The annual rate of expected population growth is predicted to be spread somewhat evenly, showing only a slight tapering off from 1.3% to 1.1% over the time period. For comparison, the state is projected to continue to grow at an annual rate of 1.07% -- very similar to the rate for Benton County.  In contrast, Franklin County is predicted to grow at a faster clip initially then slowing, or 2.7% annually in 2022 to 2.3% in 2030. These increases are still much higher than the state average.

Table 2. Population Projections, Top Ten Counties & State, 2022-2030

Source: Washington State OFM Growth Management Act

In terms of levels from 2022 to 2030, OFM predicts that Franklin County will add an additional 22,021 people with Benton County seeing an additional increase of 20,467 more people. The combined counties are expected to experience an increase in population of more than 42,000 by 2030. This is equivalent to adding a city two-thirds the size of just Richland to the greater Tri-Cities area.

Turning to indicator 0.1.1, we see that for the most recent year, 2021, the annual growth rate for the combined counties was 1.4%, exceeding both the state (0.78%) and national (0.72%) averages. The City of Kennewick had been growing at an increasing rate from 2015 to 2019 (0.76% to 2.2%) but has fallen off in the past two years, settling at 0.83% (about the state average) in 2021. After experiencing large population growth throughout the 1990s and 2000s, the annual rates of population growth for the cities of Pasco and Richland have stabilized but are still much higher than the combined counties. Since 2015, both Pasco and Richland have seen their populations grow by about 15%, or at an average annual rate of 2.5%.  (Use the radio buttons on the indicator graph to see this.)

One of the factors affecting the high growth rates in the greater Tri Cities area is the composition by race/ethnicity, in particular the relatively large share of the population that is Hispanic/Latino. According to the Pew Research Center, Hispanics drive population growth in some of the nation’s counties. “Nationally, Hispanics accounted for 51% of the nation’s population increase, a higher share than any other racial or ethnic group. At a more local level, Hispanic population growth often played a major role in whether a county’s population grew and by how much, though the impact varied widely.”

According to the Benton Franklin Trends indicator 0.3.3 Non-White Population as a Share of Total Population, as of 2020, one out of every three residents in the combined counties was Hispanic compared to one out every five people at the national level and one out of every seven people at the state level.  In Pasco, in particular, more than half the population is Hispanic and this can be associated with the city’s relatively higher rate of population growth. The share of non-white population that is Hispanic has been steadily increasing so this bodes well for the greater Tri Cities area continuing to see significant amounts of population growth above the state and national levels.