But new Census estimates released today show the region continued to be a people magnet, drawing 455,869 new residents -- primarily immigrants-- between April 2000 and July 2006. That's the ninth-largest metro area increase in the country during that time.

The U.S. Census Bureau defines the region's metro area as Broward, Miami-Dade and Palm Beach counties. The new report shows a 9 percent increase in population the past six years.

''That's a lot of people, and that's major growth for an area already as large as we are,'' said Ted Leonard, senior planner for Broward County.

MYRIAD PROBLEMS

It's also a significant enough increase to ratchet up the urgency for solving problems like traffic congestion, the affordable-housing crisis and other growth-related concerns, planners say.

''That amount of growth brings consequences,'' said Richard Ogburn, assistant to the director of research and budget at the South Florida Regional Planning Council.

``That's a lot of roads we should have built, but we're not building new roads, so that's a lot more cars on the roads we have. We've known for a long time our transportation system hasn't kept up with the growth. That's a lot of school seats and a lot of hospital beds.''

And there is no end in sight.

A slowdown in population gains during the past two years is a momentary lull, planners said. Census numbers released last month showed that between July 2005 and July 2006 the number of people moving into Miami-Dade, Broward and Palm Beach counties from other states -- known as domestic migration -- was less than the number moving out. South Florida's growth is fueled almost entirely by foreign immigration, a trend the new Census report says is happening in large metro areas across the country.

Without immigrants pouring into the nation's big metro areas, cities like New York, Los Angeles and Boston would have shrinking populations as native-born Americans move out of big cities.

In the South Florida metro area, there were 409,426 new immigrants during the period covered by the Census report.

Statewide, Florida metro areas continued to grow, with only Key West-Marathon registering fewer residents -- down 4,852. Orlando was the state's fastest-growing larger metro area, with a 21 percent estimated increase, according to the Census report.

WEST COAST GROWTH

Among smaller metro areas, Cape Coral-Ft. Meyers had the third-fastest growth rate in the nation; and Naples-Marco Island ranked seventh.

''We don't see that Florida will stop growing rapidly,'' said Stefan Rayer, research demographer for the Bureau of Economic and Business Resources at the University of Florida in Gainesville.

State and regional demographers are also predicting net domestic migration will bounce back and return South Florida to more rapid growth.

''The slowdown or plateau we've seen in the domestic migration is not a break,'' said Leonard. ``I wouldn't be surprised if we see it for another year or so until the housing market straightens out and housing costs and income achieve more equilibrium. But it's just waiting to take off again, and it will happen.''

And the region will still have huge increases in immigrants to go along with it.

''They come here because they have relatives and friends who have come before them and made the transition and established a community,'' Ogburn said. ``And the places they are leaving often have more congestion than we do. Just because things have gotten a little bit tougher here, it's not like they are going to change their mind about coming.''