Beaufort County's population boomed between 2000 and 2010, increasing 34.1 percent, according to U.S. Census figures released Wednesday.
Only three other counties -- York, Horry and Dorchester -- had populations that grew faster during that period.
Data from the 2010 census, including population totals broken down by voting age, geography and race, is being released state by state. The U.S. Census Bureau is required by law to report the findings of each decennial census by April 1, so officials can begin redistricting -- the once-a-decade exercise to redraw their legislative boundaries.
Most areas of Beaufort and Jasper counties showed growth during the past decade.
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Bluffton's population in particular has exploded, increasing by 883 percent.
"It's just the quality of life," said Mayor Lisa Sulka. "People want to live in a wonderful place."
Beaufort County Councilman Paul Sommerville said the environment -- particularly the ocean and other waterways -- is a big draw for new residents.
"It just has a huge appeal to people, and that's why were fighting so hard to protect it," Sommerville said.
Both Sommerville and Sulka said growth needs to be sustainable in the future.
"I want to see managed growth," Sulka said. "Having this (economic) downturn has showed us that we can take things a little slower."
In the two-county area, Beaufort was the only municipality to fall in population. It lost 589 people between 2000 and 2010, a 4.6 percent drop.
The number of Hispanic residents has also jumped, increasing by 138 percent in Beaufort County and 215 percent in Jasper County.
The state's population rose from 4,012,012 to 4,625,364, a 15 percent increase.
Beaufort County's population rose from 120,937 to 162,233, 34 percent increase.
Jasper County's population rose from 20,678 to 24,777, a 20 percent increase.
Bluffton's population rose from 1,275 to 12,530, a 883 percent increase.
Hilton Head's population rose from 33,862 to 37,099, a 10 percent increase.
Port Royal's population rose from 3,950 to 10,678, a 170 percent increase.
Ridgeland's population rose from 2,518 to 4,036, a 60 percent increase.
Hardeeville's population rose from 1,793 to 2,952, a 65 percent increase.
Yemassee's population rose from 807 to 1,027, a 27 percent increase.
Beaufort's population declined from 12,950 to 12,361, a 5 percent drop.
South Carolina already knows that its population of 4.6 million will give it an extra congressional district in 2012.
The more detailed census numbers released Wednesday will help the Legislature determine where to draw the new seventh district.
Most have speculated that it will be drawn around the Grand Strand. Horry County, with 269,291 people, was one of the state's fastest-growing counties. The 1st Congressional District -- represented by Rep. Tim Scott -- currently stretches from Horry County to the Charleston area and has more voters than any other in the state.
"I think the natural flow will be for the seventh district to come out of Horry with some population coming out of the Florence area," University of South Carolina political science professor Robert Oldendick said. "That's the easiest way to carve it out."
The new numbers also could add new state House and Senate seats to the coast, the Upstate and the York County area, while rural counties along Interstate 95 and just south of the Upstate will lose influence in Columbia.
The Charleston Post & Courier contributed to this report.