Perhaps the most striking trend was the across-the-board jump in the numbers of minorities in Maryland. In addition to the dramatic growth of the Hispanic population, the Asian population jumped by more than 50 percent and the number of individuals identifying as members of two or more races increasing by 59 percent.

Hispanics have had a major influence in some neighborhoods — they make up 34 percent of residents in the Census tracts that make up Highlandtown, for example. That's a three-fold increase since 2000.

Our Lady of Pompei Church, at the corner or Claremont and Conklin streets in Highlandtown, must hold three Spanish Masses just to accommodate all its Hispanic parishioners, said the Rev. Luigi Cremis, the pastor there. Eight years ago, the church offered just one Spanish Mass.

But such changes have not come without tensions. A pilot bilingual weekly Mass last year was ended after six months, when it proved unpopular with both English and Spanish speakers.

"We tried to do something to unite the two things. The church was empty," he said. "These are two worlds. One does not understand the other. We talk a different language because of the culture."

Hispanics have also helped drive growth in Baltimore County. Mercados have popped up in Parkville and Towson, and Dundalk-area bakeries say Spanish-speaking employees have helped them cater to a growing base of Hispanic customers.

"The immigrant community is like any community — they want to be in a place where they can find affordable housing, where they can live in a community that will be welcoming to them and where their children can prosper in a safe neighborhood," said Elizabeth Alex, an organizer with Casa de Maryland, an immigrant advocacy group. "For years, that's been the attraction of Baltimore County."

Baltimore County also has seen a significant racial shift. From 2000-2010, the number of black residents increased by nearly 60,000, while more than 40,000 whites have left.

The recession, local limits on development and the lack of empty land slowed growth in several Baltimore-area counties.

Howard County boomed in comparison to most Maryland localities. But its growth rate represented a slowdown for the prosperous county, which grew by more than 30 percent in the 1990s.

Stricter controls put in place after 2000 have slowed and delayed developments near overcrowded schools and intersections, said Jeff Bronow, a county demographic planner.

Now, central Columbia is about to embark on a 30-year redevelopment that could add thousands of new residents to the planned town, while Ellicott City remains the county's fastest-growing community.

"I think there's been a noticeable diversity that's all to the good," said Grace Kubofcik, a longtime Ellicott City resident, who is also president of the county's League of Women Voters chapter. "The Asian-American population has doubled and tripled," she said, and Hispanics and people from India and Pakistan are also more numerous.

White students became a minority for the first time in Howard's highly rated public schools this year, and officials from County Executive Ken Ulman on down frequently celebrate diversity — along with the state's highest household income and lowest unemployment rate.

In Carroll County, the population grew by about 11 percent since 2000. Just as in Howard, that was about half the growth rate of the 1990s.

"Over the last 25 years, it has been a population explosion," said Ellen Dix, a longtime Eldersburg resident and retired administrative assistant.

But the growth came with a price, sparking fears among county officials of overcrowded schools, congested roads and too few officers to police new residents, said Cynthia Parr, a deputy chief of staff in Carroll government.

In 1998 and 2004, the county adopted rules requiring infrastructure and services to meet certain thresholds before new developments could go forward — that helped slow population growth in the last 10 years, Parr said.

Dix expects growth to slow further in south Carroll, also known as the Freedom area, in coming years, simply because there are few places left to build homes.

"We had a lot of green space. That's gone. Developments, condos, everything came in," changing the flavor of the county from rural to suburban, said Dix, president of the Freedom Area Citizens Council.