Over the last 10 years, the South Loop area saw a population boom unlike any other Chicago neighborhood, according to recent Census estimates. Most of the new residents are white and the white population increased threefold in the last 10 years.

These changes partly reflect Chicago’s overall increase in white population. However, the neighborhood’s changes are unique and show an area transformed from sparsely developed to dense, affluent and full of young professionals.

“Historically, what you saw was the return of young professionals to the city who could not necessarily afford Lincoln Park or other Near North Side neighborhoods,” said Virginia Carlson, president of Chicago’s Metropolitan Information Center, a nonprofit research and consulting group.

Curt Winkler, a professor of urban planning at the University of Illinois Chicago, described what has happened the last ten years as a “feedback loop.”

“There was new housing that brought in entertainment and restaurants,” Winkler said. “And the entertainment and restaurants then brought in additional people.”

These population estimates come from an analysis of the latest American Community Survey data compiled by the Census Bureau between 2005 and 2009. ACS is distinct from the 10-year census: The Census Bureau is scheduled to release 2010 Census data next month.

ACS data corresponds to the 77 recognized Chicago neighborhoods. One of these neighborhoods is the Near South Side, whose boundaries are roughly south of Roosevelt Road, north of 26th Street, west of the Chicago River, and east to Lake Michigan.

Between 2000 and 2009, the Near South Side population skyrocketed 75 percent from 9,509 to about 16,000 residents. No other neighborhood came close: the next highest population increase was the South Side’s Burnside neighborhood with a 25 percent jump.

The Near South Side’s neighboring Loop and Near West Side saw population increases of 23 percent and 12 percent, respectively. Equally eye-popping was the Near South Side’s sea change in race demographics. The white population jumped 203 percent from about 2,500 residents in 2000 to roughly 7,500 residents in 2009. The black population, meanwhile, stayed basically the same – going from about 6,100 to an increase of just 45 residents. The neighborhood’s small Latino population increased slightly to 802 residents.

What has happened on the Near South Sides bears only a tenuous similarity to citywide trends. Whites will likely become the city’s biggest racial group for the first time since 1980. Chicago, however, is actually estimated to have lost 45,000 residents in the last 10 years.

Kevin Jackson, executive director for the Chicago Rehab Network, points out that in many neighborhoods white residents pushed out black residents as housing prices increased.

In the Near South Side, though, blacks were not displaced – it’s just that white residents came back in droves, mainly to the new South Loop high rises. Also, while overall median city income slightly declined from 2000 to 2009, it increased by almost 40 percent in the Near South Side. The median Near South Side household income is almost $80,000 compared to about $47,000 citywide.

One reason for these demographic changes was the previous under-development, Jackson said.

“The increase in population was a no-brainer given that there wasn’t housing here before,” he said.

City policies concerning development and beautification also played a role, Winkler notes. But the biggest reason, he said, was the Near South Side’s proximity to downtown jobs. Jackson suggests that South Loop development was fairly inevitable.

“If you have a lucrative housing market twelve blocks north of downtown, why not have the same 12 blocks south of downtown?” he said.