The Lowcountry has four of South Carolina's five fastest-growing municipalities, but some rural towns and wealthier beach communities haven't seen much population growth at all, according to the U.S. Census Bureau's latest estimates.

The South Carolina cities that have added the most people include Mount Pleasant, Summerville, Rock Hill, and Charleston, all of which added more than 9,000 new residents. North Charleston added more than 5,000 new residents and was the fifth fastest growing.

The South Carolina cities that rounded out the Top 10 fastest growing were Greer, Mauldin, Myrtle Beach, Lexington and North Myrtle Beach. Goose Creek ranked 11th.

Among the nation's 254 largest cities, those with more than 100,000 residents, only 57 grew at a faster rate than Charleston between 2000 and 2005, the figures show.

Mount Pleasant has surpassed Greenville as the state's fourth-largest city, and Summerville is poised to surpass Spartanburg and Sumter by the 2010 Census to become sixth largest. Charleston is growing so much faster than Columbia that it seems likely to regain its position as South Carolina's largest city within the next decade.

The census estimates also point to other changes taking place in the region.

While many Lowcountry cities are booming, several beach areas, including Kiawah, Seabrook and Sullivan's islands, are losing full-time residents.

Also, some of the distant rural communities such as Awendaw, Bonneau, Jamestown and St. Stephen are seeing little or no population growth.

Charleston has added so many new residents largely because the city had annexed large undeveloped areas that are being built out today, such as Daniel Island, Mayor Joe Riley said.

Stephen Jones, who lives on Daniel Island Drive, never expected things to change as fast as they have.

'We moved to Charleston in 1998 and since that time it has just gone nuts, but Daniel Island in particular has really seen a boom,' he said. 'You've got more convenience, but obviously with convenience, there's more traffic.'

Dump trucks and other construction traffic passed his house in ever-growing numbers, and he urged the city to install speed humps or a stop sign at a nearby intersection. He was told no, but a year later, a stop sign went up.

The changing traffic in front of Jones' house is symptomatic of the growth drawbacks other communities are seeing. In 2000, Mount Pleasant began limiting the number of residential building permits it would issue each year so that growth would slow until new infrastructure, including road improvements, caught up.

Even though the town grew by 4 percent a year, it added more new residents between 2000 and 2005 than any other South Carolina city, and traffic remains a hot issue.

Jim McGraw has lived in Summerville for 13 years and said he isn't surprised at the town's soaring estimated population.

McGraw said the growth underscores the importance of making important decisions on road projects. He has questioned plans to extend the Berlin G. Myers Parkway because he said it could claim much of Dorchester County's road-building budget and not make enough of a difference in traffic flow. 'It's just a waste of taxpayers' money,' he said.

Riley said Charleston's growth wasn't sharp enough to consider building permit caps or other limits but that it underscores the importance of special committees to look at growth in West Ashley and Johns Island.

'The traffic is of concern to us and to our citizens, and that's why the half-cent sales tax is so important,' he said. 'That's why good land-use planning is so important.'

Isle of Palms Mayor Mike Sottile said he doesn't disagree with estimates showing his city lost a few residents since the 2000 Census.

'The voter registration has declined. That caught my eye last year, when we had an election,' he said. 'Between insurance and taxes, the value of property is so high that what's happened is people who have been living on fixed incomes, they're cashing out. Unfortunately, that's happening.'

Sottile estimated that of all the homes, condos and town homes on the Isle of Palms, 60 percent are rentals, while 40 percent are year-round homes. As the number of rentals rises, that can increase tension with the remaining residents, who may experience more noise and parking problems during the peak rental months.

'It's affecting the quality of life,' Sottile said. 'It's something that we as a city are going to have deal with some point in time.'

The Isle of Palms is not alone. While Folly Beach and Edisto Island have grown in the past five years, the estimates show that Sullivan's, Kiawah and Seabrook islands had fewer residents in 2005 than five years earlier.

Dan Hatley, a planner with the Berkeley, Charleston and Dorchester Council of Governments, said this population plateau likely reflects a lack of raw land for new homes. 'Some of them are building out. There is just not much space left on Sullivan's,' he said.

Beach communities aren't alone. Census estimates show flat or negative population change in several rural communities outside Berkeley, Charleston and Dorchester counties' metropolitan coref.

Estimates for the towns of Awendaw, Bonneau, Cottageville, Harleyville, Jamestown and St. Stephen showed virtually no population change, although the figures only reflect what's going on in the towns' limits, not in the unincorporated areas around them.

'They seem to be just far enough from the urban area,' Hatley said. 'They're not being targeted yet for commuter traffic.'

While the Lowcountry is growing quickly, its pace isn't among the top in the nation. Elk Grove, Calif., had the fastest growth rate among cities with at least 100,000 residents. The town near Sacramento was incorporated less than six years ago but has seen its population rise by 12 percent, to 112,338.

Three other California cities made the list of the 10 fastest-growing large cities. Florida also had three cities on that list, including Port St. Lucie (third), Cape Coral (fifth) and Miramar (eighth). The list was rounded out by two cities in Arizona and another one not far from that state: North Las Vegas, Nev., which ranked second.

In terms of sheer numbers, Phoenix added the most people in the past year, while San Antonio; Fort Worth, Texas; North Las Vegas, and Gilbert, Ariz., rounded out the top five. New York City is secure in its position as the nation's largest city, with 8.1 million people ? more than twice the population of Los Angeles, which was second.

Among the 10 largest cities, San Antonio has replaced San Diego as the seventh most populous city.

The new estimates are based on Census 2000 population counts that were adjusted using information on building permits and other estimates as of July 1, 2005. The figures don't account for the impact of Hurricane Katrina, which struck two months later.

To see the summary of census estimates for S.C. municipalities, go to ^{www.charleston.net/webextras.}