County’s Rate of Growth Outpaces State : Census: The population increased 26.4% to 669,016 during the 1980s, led by a 227% surge in Moorpark.

Despite the emergence of a strong slow-growth movement, Ventura County grew at a faster rate than Santa Barbara, Orange or Los Angeles counties during the 1980s, according to final 1990 census figures released Friday.

The county’s population increased 26.4% to 669,016 over the past decade, a rate of growth also slightly higher than California as a whole, the figures show.

Ventura County’s population, which surged by 139,842 in 10 years, was led by booms in Thousand Oaks, Camarillo, Simi Valley, Oxnard and especially Moorpark, which has grown by 227% since incorporation in 1983.

New housing tracts accounted for much of the growth in each of those cities during the past decade. Oxnard’s population also has soared because of the increasing number of poor families who live together in apartments, houses and garages, planners said.

Ojai, which imposed strict limits on building permits, and Port Hueneme, which had little vacant land left to develop, grew the least--11.7% and 14.1%, respectively.

For comparison, increases in neighboring counties were 24.7% for Orange, 23.7% for Santa Barbara and 18.5% for Los Angeles. The state grew from 23.7 million residents to 29.8 million, about 25.7%, during the decade.

The new Ventura County figure of 669,016 reflects about 18,000 more residents than estimated in a preliminary U.S. Census Bureau count last year.

That is significant, county administrators said, because the thousands of additional residents will mean $3.6 million more in state and federal subsidies to the county each year during the 1990s--about $200 annually for each person.

Officials in Oxnard, where nearly 5,000 residents were added to last year’s count, said the higher figure will mean a windfall of about $350,000 a year in state funds, or about $75 a person.

California cities receive vehicle fees, gas and cigarette taxes and other revenue in proportion to their populations.

“We’re delighted,” said Karl Lawson, head of Oxnard’s aggressive census project, which featured a Censusmobile that cruised low-income neighborhoods and got residents to fill out forms on the spot.

“We believe this figure is much closer to our actual population than was the census in 1980,” Lawson said. “We think we’ve finally overcome that undercount.”

Oxnard, the county’s largest and poorest city, has a population of 142,216, the Census Bureau reported, which is 12,000 higher than the official state estimate in 1990.

“Our focus was to count those families who are sharing residences, and I think we have,” Lawson said. Oxnard’s population soared in the final count because the city continued to hand out simplified, one-page registration forms on street corners through mid-October under a special census program, he said.

The final census also found about 5,500 more residents in county unincorporated areas such as Oak Park, where officials had complained that entire subdivisions had been missed.

County officials applauded the final census, saying it had answered early concerns of missed neighborhoods and also seemed to have avoided the large undercounts claimed in 1970 and 1980.

“It looks like a very good count,” senior county planner Steve Wood said. “It is very close to the state estimate and to what we thought was accurate.”

The state Department of Finance estimate for January, 1990, was 668,553, just 463 off the final census figure. Ventura County and nine of the 10 cities in the county challenged the preliminary census, insisting that thousands of dwellings had been missed.

But the adjusted figures released Friday were, in some cases, much higher than city officials had anticipated.

In Camarillo, Assistant City Manager Larry Davis said he could not explain how federal canvassers found an additional 2,537 people in their second go-round in his city.

But Davis said the boost is significant, because it puts the city’s population above 50,000 and allows it to apply for a broader array of federal programs.

Thousand Oaks was the only local city not to challenge the early census count, but still gained 1,557 residents in the final count. Planner John Prescott said, “They said their figures weren’t hard and fast.”

The 1990 census is intended to reflect population for April 1, 1990. And part of the difference between the preliminary figures and final numbers reflects new dwellings completed between Jan. 1, 1990, when the census did its initial count, and April 1, officials said.

The next round of census figures for California communities is expected in early March and must be released by April 1, census spokeswoman Una Kuan said.

Those figures will include racial breakdowns so detailed that they will define each city block, she said. Also, the information will be a used as a basis for formation of the seven new congressional districts that California gains because of its booming population, she said.

Even as local planners gear up to digest the rush of new information, Wood said that forecasts for the 1990s show continued rapid growth, although at a slightly slower pace. The county predicts 13,000 to 15,000 new residents each year for the next decade, about the same as during the 1980s, Wood said. That would mean a Ventura County population of 788,000 in the year 2000, he said.

GROWTH RATES

1990 1990 % change Name 1980 prelim. final 1980 to 1990 Moorpark 7,798 24,912 25,494 +226.9* Camarillo 37,797 49,766 52,303 +38.4 Thousand Oaks 77,072 102,795 104,352 +35.4 Oxnard 108,195 137,468 142,216 +31.4 Simi Valley 77,500 99,316 100,217 +29.3 COUNTYWIDE 529,174 650,880 669,016 +26.4 Fillmore 9,602 11,686 11,992 +24.9 Ventura 74,393 91,744 92,575 +24.4 Santa Paula 20,552 24,443 25,062 +21.9 Port Hueneme 17,803 19,932 20,319 +14.1 Ojai 6,816 7,501 7,613 +11.7

* Since incorporation in 1983