Largest Cities Reflect Shift to West, 1990 Census Finds : Population: Los Angeles beats out Chicago as No. 2 in U.S. California lists 18 of 29 places reaching 100,000.

Six of the nation’s 10 largest cities are now west of the Mississippi River, and most of the 29 cities to reach a population of 100,000 in the last decade are California suburbs, according to final 1990 census data released Friday.

With the news that the country’s westward shift has enlarged the suburbs and shuffled the roster of major cities, the Census Bureau also confirmed for the first time that Los Angeles--up half a million people since 1980, to nearly 3.5 million--is the nation’s second-largest city.

Chicago, which had been No. 2, was among several cities in the East and Midwest to slip in population. Chicago dropped below 3 million people for the first time since the 1930 census, and in the past 40 years it has lost 837,000 people--23% of its populace.

New York, meanwhile, remained No. 1 and grew by a quarter-million people to 7.3 million, reversing a decline that began in the 1970s.

The trend toward population loss plagued many older cities in the East and Midwest in the 1980s, but not in California and the rest of the Sun Belt West.

Houston edged past Philadelphia to become the fourth-largest city. San Diego jumped to sixth place in this census, ahead of Detroit, Dallas, Phoenix and San Antonio. Baltimore, which had been in 10th place, slipped off the list.

Friday’s figures are the last in a series of three initial reports on the 1990 census. Details on ethnic minorities, education and other facets of the population will come later. The populations of the states were announced earlier and they showed that California would gain seven seats in Congress, which would make it the first state to have more than 50 elected representatives.

The figures released this week normally would have been considered final, but this year’s results await a ruling on lawsuits filed by a number of large cities, including Los Angeles, Chicago and New York. The suits allege that the Census Bureau fails to count many individuals, especially the poor and members of minority groups who may be wary of participating in government surveys.

Critics have urged the Department of Commerce, which oversees the census, to make statistical adjustments to compensate for errors in the count. Yet some demographers doubt that such adjustments would make the census more accurate.

In Friday’s numbers, the fastest-growing American city of 100,000 or more is Mesa, Ariz., a suburb of Phoenix that swelled by 89% in the 1980s. In California, 42 smaller towns and cities saw faster growth in the decade, and 18 places here crossed the 100,000 threshold to rank as medium-sized American cities.

At the end of the decade, 195 American cities were home to more than 100,000 people, a list that now includes suburbs such as Thousand Oaks, Simi Valley and Santa Rosa that may not be familiar names outside California.

Most of the new cities do not resemble the traditional cities of the past. There is usually no Main Street, but almost invariably a freeway at the heart of the city. Sometimes there are no department stores or shopping malls, and often no ethnic minority neighborhoods.

Some of the cities are so new that they were not incorporated before the 1980 census.

Santa Clarita, one of the new 100,000-person cities, was a collection of unconnected subdivisions in the canyons north of Los Angeles in the last census. Moreno Valley, another example, was a mostly empty piece of desert east of Riverside.

These suburbs had the most spectacular population rise, but the census figures show that growth in California in the 1980s was a widespread phenomenon, altering the inland deserts and Sierra foothills along with the San Joaquin Valley and the older cities.

Every county in the state gained population in the 1980s. Riverside County, which grew by 76%, was the fastest-growing, followed by its Inland Empire neighbor, San Bernardino County, which grew by 58%.

The next 15 counties in growth ranking were north of the Tehachapi Mountains that commonly divide Southern California from the rest of the state. Amador County, in the Sierra Nevada east of Sacramento, was the fastest-growing Northern California county.

The state has eight counties with a population of more than 1 million, compared to five counties in the last census. Southern California has five: Los Angeles, San Diego, Orange, San Bernardino and Riverside.

Also, nearly all of the 456 cities in California grew in some measure during the 1980s. Three dozen of them more than doubled in size, led by Temecula and Palmdale.

The new data also confirms that San Jose, once a farming outpost, has surpassed San Francisco to become the largest city in Northern California and the third most populous in the state, behind Los Angeles and San Diego.

Only 38 cities in California lost population, and most were either small and isolated communities--such as Point Arena and Trinidad on the North Coast--or pockets of affluence where the population is older and fewer children are being born. Beverly Hills, Palos Verdes Estates and San Marino are examples of affluent cities in which the population dropped. Berkeley and Santa Monica were the largest cities to experience drops in population.

The pattern of suburban sprawl and of small towns and nondescript suburbs exploding into full-fledged cities--which have come to characterize California--is also evident in other parts of the country.

Four of the new mid-sized cities are in Texas. Laredo, on the Mexico border, reflects the huge influx of Latino immigrants into the United States during the past decade. Two others, Mesquite and Plano, are suburbs of Dallas. The fourth is Abilene.

Two of the new mid-sized cities--Scottsdale and Glendale--are suburbs of Phoenix. Two other new members of the 100,000-plus club are state capitals: Salem, Ore., and Tallahassee, Fla. Overland Park, Kan., is a suburb of Kansas City.

Lowell, Mass., which until World War II was a thriving industrial metropolis with a population well above 100,000, had slowly declined over the decades. But it has experienced a recent resurgence thanks to a thriving new high-tech computer industry and has gone over 100,000 again.

Prosperity brought about by computer business has had similar effects on other parts of the country. For instance, Durham, N.C., where there is a growing computer-research industry, has grown by more than 35% in the past decade, and neighboring Raleigh has grown by nearly 39%.

Most cities and towns that grew rapidly in the last decade are in thriving industrial areas, or are near large cities, or have liberal annexation laws that allow them to expand their boundaries as their populations grow, said Richard Forstall, chief of the Census Bureau’s population distribution branch.

“These have been characteristics of California and the West. They have certainly not been characteristic of the Northeast,� Forstall said.

Since 1980, five cities fell from the 100,000-population list. Roanoke, Va., and Columbia, S.C., both had declining populations, but only within the city limits, not in adjoining suburbs. Youngstown, Ohio, and Pueblo, Colo., have been plagued by dying steel industries. “And Davenport (Iowa) has had a little mixture of everything,� Forstall said.

Even in cities that experienced tremendous growth, there was sharp criticism of this week’s figures.

“We still believe many residents were not counted,� Los Angeles Mayor Tom Bradly said in a statement. “This undercount could mean the loss of millions of state and federal dollars needed to adequately provide services to those most in need. Ironically, these are some of the same people most likely to have been missed in the census count.�

New York officials were pleased that the city’s count did not fall as short as they feared. New York’s gain of 3.5% was higher than in early projections, and reversed a loss of more than 800,000 in the previous decade.

Detroit also got relatively good news from the census this week. The city has lost 14.6% of its population, less than first believed, and thus will not drop below 1 million and lose various forms of federal assistance.

Nonetheless, officials from these cities, along with many others around the country, continued this week to criticize the 1990 census for missing too many of the country’s residents. Overall, the bureau found that there were 248.7 million living in the United States at the end of 1990. Last October, the bureau had projected it would find 253 million, a gap of 4.7 million.

There were 226.5 million people counted in the 1980 census.

AMERICA’S 10 LARGEST CITIES

1990 Percentage 1980 Rank City 1980 1990 Change Rank 1 New York 7,071,639 7,322,564 3.5 1 2 Los Angeles 2,968,528 3,485,398 17.4 3 3 Chicago 3,005,072 2,783,726 -7.4 2 4 Houston 1,595,138 1,639,553 2.2 5 5 Philadelphia 1,688,210 1,585,577 -6.1 4 6 San Diego 875,538 1,110,549 26.8 8 7 Detroit 1,203,368 1,027,974 -14.6 6 8 Dallas 904,599 1,006,877 11.3 7 9 Phoenix 789,704 983,403 24.5 9 10 San Antonio 783,940 935,933 19.1 11

Source: U.S. Census Bureau Times director of computer analysis Richard O’Reilly contributed to this story.