Columbia, 10 years old and proud of it, blew out the candles for its birthday party Monday with brass bands, skydivers and the thunder of red, white and blue fireworks that lit up the night.

An estimated 50,000 persons who crammed the shores of Kittamaqundi, Columbia's downtown lake, were on hand as the party ended with the now-traditional pyrotechnics staged each year by Howard County's all-volunteer Fourth of July Committee.

This year's fireworks in Columbia drew crowds that were second only in the Washington-Baltimore area to those at the fireworks at the Washington Monument. The Columbia fireworks also attracted an estimated 10,000 to 15,000 more people this year than last year, police said. And even with such a large crowd, a Howard County Police spokeswoman said: "It was a very nice evening. There were no major problems whatsoever."

The new town's Fourth of July celebration brought to a close 17 days of birthday activities that included a four-day City Fair, visitors, a carnival, a 10-event Olympics and a 16-mile mini-marathon that was run in 90-degree heat.

There were also retrospective seminars, ceremonies for grand openings, rededications and plaque presentations and lots of parties that ranged from blue-jean to fancy-dress affairs.

Patricia Roberts Harris, secretary of Housing and Urban Development, opened an exhibit on new towns at the Columbia Mall and described Columbia as a town that "people of all races and incomes know is a superior place to live and to raise their children."

Four members of the original work group that helped developer James W. Rouse brainstorm in the early 1960s on the ingredients of a successful city returned to pronounce themselves generally pleased - and sometimes amazed - at the results.

And Frazar B. Wilde, retired chairman of Connecticut General Life Insurane Co., Columbia's first and leading sourcce of capital, came back to express pride in 10 years' worth of progress.

"There never will be utopia . . . but (Columbia's) a nicer place to live, with nicer people than most," declared Wilde, for whom Wilde Lake, Columbia's first village, is named.

With nearly 44,000 residents, some 750 businesses and 20,000 jobs, Columbia is now nearly half-grown. When completed, probably in the early 1990s, Columbia is expected to have about 100,000 residents and 40,000jobs.

The birthday celebrations included the formal opening of Columbia's eighth village, King's Contrivance. A total of nine village is planned for the town's 14,000 acres.

While not everything that was hoped for in Columbia has come to pass, the town is young and there is still time, several members of the original work group said in reporting their impressions to the community.

The work group consisted of 15 experts from a wide variety of discipline who met with Rouse Co. officials over a periods of six months, beginning in November, 1963.

Their task, Rouse explained at a birthday forum sponsored by the Columbia Foundation and attended by more than 600 residents, was to help define the concepts and components a city would need to provide the best environment possible for the people who would live there.

"We said we really didn't know enough to build a city," Rouse said. "We were architects, engineers, planners, bankers . . . we needed (inout from) people who had been dealing with the lives of people," such as the doctors, educators and sociologists who joined the work group on a per diem basis.

The group's observations about Columbia today included Paul V. Lemkau's comment that "the Columbia is rather like a member of a good army. He gripes."

"But," added Lemkau, who is professor of mental hygiene at The Johns Hopkins University, "it is not sullen griping. It doesn't stop at the gripe. It gets to the point of finding alternatives."

As examples, he cited a recent race relations study in one Columbia village for the Columbia Association, which owns and operates the town's community buildings and recreation facilities.

The other work group members at the forum were Henry M. Bain Jr., a political scientist and authority on urban transportation, Nelson N. Foote, chairman of the sociology department at Hunter College, and Donald N. Michael, who is professor of planning and psychology at the University of Michigan.

Foote noted that goals for low and moderate-income housing in Columbia have been "frusted," but added that was due to "circumstances out of your control . . . when Nixon cancelled funds for subsidized housing."

Low and moderate-income housing now accounts for about 6.5 per cent of Columbia's homes, compared to original projections of about 10 per cent. The median income of Columbia families is more than $25,000 a year.

Work group members also expressed chagrin at the lack of cable television in Columbia, the uneven match of jobs and housing, the inability of the subsidized bus system to wean residents from their cars and the continuing dilemma of providing activities attractive to teenagers and young adults.

Plans that have been realized, although they once seemed almost too ambitious, include Columbia's prepaid health care program and its jointly owned interfaith religious facilities, they said.

The work group also praised the neighborhood village system of development, which Lemkau said was designed to give residents "a feeling of loyalty . . . a harkening back to the America small town tradition."

Michael, who chaired the work group, commented approvingly on the variety of "inventive" community institutions developed by residents to meet specific needs.

"The whole sense of what needs to be done is heightened" in Columbia, he said. "In other communities, these problems wouldn't be noticed, much less worked on."