The Fairfax County Board of Supervisors, backing down after more than a year of confrontation, yesterday voted to accept the Virginia state highway department's recommended route for the Springfield Bypass, a $200 million highway that will curve 35 miles through the county like an outer beltway segment.

The board's unemotional debate and 7-to-2 vote closed a virulent controversy that toppled a highway commissioner and became an issue in last year's gubernatorial election. The county's concession also is good news for two major developers in western Fairfax who will get an interchange with Interstate 66 on their land.

County officials yesterday claimed to have won a compromise, with the state giving ground on the character of the proposed highway. For the most part, however, state officials only adopted a more conciliatory tone.

Highway commissioners Joseph Guiffre and T. Eugene Smith promised to work to minimize the impact on neighborhoods along the route, limiting the road to four lanes and avoiding huge interchanges when possible. But the state made no formal concessions to the county.

The board will hold a public hearing on Dec. 13 before officially placing the disputed segments of the Springfield Bypass on its master plan.

Once that is accomplished, the environmental impact statement that was completed last year but held in limbo by the controversy can be submitted to the federal government.

Even then the proposed highway, which has been discussed for more than a decade, faces an uncertain future.

The county has not earmarked funds for the road, and state and federal highway construction budgets have declined in recent years.

County Board Chairman John F. Herrity said yesterday he believes the road will be built in segments, with top priority going to the interchange at I-66 in western Fairfax and the access to Shirley Highway (I-95) and the planned Franconia Metrorail station in Springfield.

Herrity declined to predict when either segment might be constructed, but he said the entire road is crucial to the county's future economic development.

"Twenty years ago, everyone thought all the rush-hour traffic would be going to downtown Washington," Herrity said. Today, he said, the county expects more than 60 percent of its rush-hour traffic to be driving to jobs within Fairfax in 1990.

Supervisor Audrey Moore, however, called the county position a "sellout" that defeats the original purpose of the road while serving the interests of the county's influential land development industry.

"What is it now but a way to open up the western portion of Fairfax County and to encourage more development out there at a time when our financial resources are strained and we can't afford it?" said Moore, who with supervisor James M. Scott voted against the state plan.

The Springfield Bypass, as its name suggests, originally was conceived as a spur to relieve congestion on Old Keene Mill and Braddock Roads by taking Springfield commuters onto I-95. It eventually grew into a cross-county highway stretching from Reston and Rte. 7 in the north to Fort Belvoir and Rte. 1 in the south.

The Virginia State Highway and Transportation Commission, which sets policy and allocates road funds throughout the state, endorsed the cross-county concept in August 1981 but rejected the county's proposed alignments at I-95 and I-66. The state alternative became a political issue when it was revealed that Northern Virginia's then-highway commissioner, William B. Wrench, owned land near the state route at I-95 and that Wrench's friend and lawyer, developer John T. Hazel, coowned land bordering a full interchange at I-66.

State highway officials defended their alignment as the best for traffic flow on the interstates, but Wrench was criticized for failing to make his land ownership public before proposing and voting for the state route. A Republican fund-raiser for gubernatorial candidate J. Marshall Coleman, Wrench resigned from the powerful state highway commission under pressure after his role was disclosed.

Wrench could not be reached for comment yesterday, and Hazel, who owns several hundred acres with Milton V. Petersen along the bypass route, declined comment.