Planning officials say 2006 has been another year of steady growth in Columbia County, with the population now nearing about 106,000.

As the figure continues to increase, some officials are eyeing its effects, from the positive and the negative side.

"I think the biggest impact is to be listed in areas of over 100,000, whether it's a city or a county," said Columbia County Commission Chairman Ron Cross. "A market or a county that's above 100,000 takes on a different significance for retail and people wanting to expand their businesses."

The last official Census figure, taken in 2000, showed the county population at 89,000.

For next year, though, Columbia County Planning Director Jeff Browning projects that the county will again have an average growth figure of about 2,500 people, bringing its total at the end of 2007 to near 109,000.

In light of such growth, Mr. Cross says he's looking at an impact fee that could be charged to developers to help pay for public safety.

"It's definitely going to be brought up," he said, adding that talks could begin as early as February.

There's also the school system to consider.

Mirroring the county's growth, the Columbia County school system is in a state of rapid enrollment expansion.

"Looking at student-growth history, we're in one of the more accelerated periods in the last 25 years," Superintendent Tommy Price said.

More than 21,000 pupils currently attend public schools in the county. By 2011, school officials expect the enrollment number to grow to nearly 25,000.

School construction projects include a new elementary school scheduled to open in August, 12-classroom additions to be built at River Ridge and Lewiston elementary schools by August, a new middle school on Blackstone Camp Road scheduled to open in August 2008, and a new high school on Chamblin Road due to open in August 2009.

Despite similar woes, school officials don't measure growth the same way as county officials.

Factors such as the number of retirees and singles moving into the county don't figure much into school-related growth rates, Mr. Price said.

Mr. Browning said the county factors in an average number of people per household in its projections, adding that the county's average is at about 2.87 people per home, a figure that has decreased since 1990.

"We're no longer just strictly the 2 kids and the two dogs and the station wagon like we used to be,'' Mr. Browning said.

Dave Van De Weghe, of Columbia County's planning office, said new home sites continue to increase in the county, with as many as 1,276 new units possible for approval this year.

That figure is 16 percent less than the number of new housing units approved in 2005, but 2006's housing figures are comparable to the years 2002-2004 and 77 percent greater than 2001's figure.

Staff Writer Donnie Fetter contributed to this article.