The Washington area's population increased markedly last year to 3,429,500, continuing a growth spurt that began in 1980, according to new U.S. Census Bureau estimates.

The nearly 1.8 percent rise over 1983 -- a gain of 60,000 people -- was the steepest in recent years. During the 1970s, the area's annual growth rate had slowed to an average of 0.7 percent. But since 1980, the rate has nearly doubled, climbing by 1.3 percent.

In a report released yesterday, the Metropolitan Washington Council of Governments attributed the recent upswing to several factors, including "a resurgence of growth in the counties around the Beltway." Fairfax and Montgomery counties showed sizable increases.

The report also cited "a stabilizing of population in the central jurisdictions." The District's population leveled off last year at 623,000 after previous decreases. Alexandria and Arlington County had slight increases after earlier declines.

Officials said these shifts more than offset a slowdown in growth in outlying suburban areas, including Loudoun, Prince William, Frederick, Calvert, Charles and Stafford counties. These areas have shown increases of 2.8 percent a year in the 1980s, compared with 4.1 percent annually during the 1970s.

John C. McClain, the council's metropolitan development director, warned that local governments may be "returning to some of the problems they had in the '60s," when population rose rapidly. The renewed growth, he said, may signal a need for more roads and new schools in some suburban areas. At the same time, he said, the stabilization in population may benefit the central localities, including the District, by providing a solid tax base to finance public services. On the whole, the region's growth appears to reflect a relatively strong local economy, he said.

Donald E. Starsinic, chief of state and national estimates for the Census Bureau, said yesterday that the new statistics have not yet been analyzed. A report is expected later this year.

A recent Census Bureau study pointed to similar trends, including faster suburban growth, throughout the country.

Officials said the growth in Washington's suburbs, along with other trends, appears to reflect employment gains in suburban communities, shifts in birth rates, mounting traffic congestion in outlying areas, construction of lower-priced housing in some close-in suburbs and other factors.

From 1980 to 1984, the area's population climbed by 178,600, nearly as large an increase as occurred in the previous decade, according to the Census Bureau estimates. The population rose by 211,200 from 1970 to 1980. The increases were mainly in the suburbs.