I recently highlighted a study from Wendell Cox that shows regional population growth is actually dispersing away from the urban center of Seattle.

Wendell says:

The dispersion of Seattle, like that of metropolitan regions around the nation and the world, has been going on for decades. The city of Seattle has accounted for only 5 percent of the metropolitan region's population since 1950 with suburbs and exurbs accounting for the vast majority of the nearly 3,000,000 increase.

A liberal environmental group called Sightline took issue with some of Wendell's findings. So I asked Wendell about this and here is his response:

Sightline Daily takes issue with our characterization of Bellevue as an “edge city,” noting it to be “25 miles from the edge of the metropolitan region” and “only 10 miles from downtown.” Sightline Daily is apparently unaware of the meaning of the term “edge city.” An “edge city” is a major employment center outside the central business district (downtown).  “Edge city” became a part of the language as a result of Joel Garreau’s 1991 book, Edge City: Life on the Urban Frontier. Garreau cited Bellevue in the book.

We provide an analysis from 1950 because that is the first census year in the modern suburbanization that resulted from the democratization of home and car ownership. Sightline Daily criticizes our Figure 2 as “difficult to fact-check.” That figure shows the city of Seattle having virtually flat-line growth from 1950 to 2010 compared to the metropolitan region. The data is easily available on the internet through Google searches.

Sightline Daily would have preferred that we categorize Tacoma and Everett as historical core municipalities, along with Seattle. They are not in the urban core, but are rather older, smaller municipalities that have been engulfed by the expansion of the metropolitan area. Nonetheless, the  Sightline Daily categorization (calling Tacoma and Everett core) would reduce core growth from 8.0 percent to 7.3 percent, and increase suburban growth from 14.1 percent to 15.2 percent. This would have made the case even more compelling.

Finally, Sightline Daily would like a “more sensible definition” of the metropolitan area. The Office of Management and Budget (OMB) is the official authority for designating and defining metropolitan areas and combined statistical areas. Our analysis uses their definitions.

The population dispersion evident in the Seattle area mirror the general trend in the overwhelming majority of urban areas, not only in the United States, but also Western Europe, the balance of the high-income world and many developing world urban areas.

I think the Sightline piece actually agrees with Wendell's main point that population is growing faster in the suburbs, outside Seattle, but for some reason they dispute some of his definitions and then personally attack him (which is a typical response from liberal environmentalists). As you can see from Wendell's comments, he knows what he is talking about.