In the past four months, the Fairfax County Board has done something that would have been unthinkable on the growth-oriented board last year: It said no to two large commercial projects sponsored by John. T. (Til) Hazel, the county's premier developer.

The rejection of Hazel's projects -- one in Centreville and the other in Vienna -- signaled a dramatic shift that has seen most supervisors, avid champions of growth during the past decade, assume a new, more critical posture toward development.

After a decade of intense growth, an antidevelopment backlash is sweeping through Fairfax, alarming most of the supervisors, who are up for reelection next year, and prompting many to retreat from their longstanding conviction that what is good for developers is good for the county.

"They're beginning to wake up now. We just hope it's not too late," said Ann Csonka, a Fairfax resident who helped lead a drive to limit development in the Herndon area. Residents there took to the streets carrying signs recently to protest a project that many said would further aggravate the already serious traffic congestion.

"I think they're starting to get the message," agreed Richard Korink, who led a similar drive in Centreville.

Troubled by the antigrowth sentiment, developers say they have become reluctant to press for large-scale commercial developments that easily would have won the county's approval six months ago.

"It's almost impossible to conduct zoning in this county now," said Mark Bettius, a Fairfax attorney who appears frequently before the supervisors on behalf of some of the area's major developers.

"If you had anything remotely controversial, good common sense would tell a developer to wait until after the next election," said Suzanne H. Paciulli, vice president for commercial development at Mount Vernon Realty Co.

Like a number of developers interviewed in recent weeks, Albert J. Dwoskin, president of A.J. Dwoskin & Associates, said politics has become a key factor in Fairfax's planning and zoning decisions. "We didn't elect martyrs," he said. "There's an election coming up, and I don't think being an advocate of development is going to get any of them more votes."

Developers take comfort in the belief that the supervisors will return to their previous voting patterns once the November 1987 election is over. Paciulli predicted that "a sense of calm will come back" after the balloting next year, in which all the board's seats will be up for election.

"I've watched these election year cycles before," said Dwoskin. "It comes and goes."

For now, though, there is an estrangement between most supervisors and developers. Those strained relations between formerly strong allies have been fueled by a citizenry that has grown weary of the increasingly overcrowded conditions on roads and in schools.

Many voters blame overbuilding and they have discovered that they can fight -- and help defeat or scale down -- some of the projects they blame for their discomfort.

"What we're seeing is that there is no citizen support for these projects and the board is saying, 'Forget it,' " said Supervisor Thomas M. Davis III (R-Mason). "People are in no mood to compromise right now. They're saying they want it stopped."

The supervisors first recognized that increasingly hostile development climate last winter, when some of the area's most high-powered developers sought to transform the county's rural southwestern corner into a major commercial center. The supervisors, in the face of relentless community opposition, reluctantly vetoed the developers' plans for Centreville in a midnight vote in March that left deep personal and political scars.

Two months later, residents pressed the board in Vienna, where developers were seeking to build high-density commercial parks around a Metrorail station. As in Centreville, community groups aggressively opposed the plan, and the board acquiesced by handing the developers a second consecutive setback.

On the losing side in both battles was Hazel, one of the county's favorite and most favored developers, who has won a string of zoning decisions during the past two decades. That the supervisors would risk alienating the influential Hazel was, to many, the supervisors' clearest acknowledgment of the depth of the antidevelopment sentiment.

Fairfax Republicans and Democrats alike viewed the special election in the Providence district two weeks ago as yet another manifestation of that sentiment. In that contest, Democrat Katherine Hanley registered a lopsided victory running on a platform that stressed controlled growth.

The antidevelopment feeling has been reinforced, some politicians say, by the summer-long controversy surrounding County Board Chairman John F. Herrity, who for more than a decade has argued that large-scale development can translate into a much-needed infusion of dollars and jobs for what once was a bedroom community.

After a two-month investigation, the county prosecutor last week charged Herrity with violating the Virginia public disclosure law by participating in a controversial rezoning case without revealing his business relationship with the developer appearing before the board. Herrity, who has denied the charge, is scheduled to stand trial Aug. 21.

Most supervisors say that they have always been critical of development and that they are not adopting a new stance. They acknowledge, however, that many of their constituents are tired of congested roads and believe that Fairfax has become overwhelmed by development.

Antidevelopment sentiment is not new to Fairfax. In the late 1960s and early 1970s a number of people won seats on the county board by pledging to slow growth. During that period, and largely as an outgrowth of the zoning scandals of the 1960s, a sewer moratorium and other measures were undertaken in an attempt to block further development. Most of the measures were invalidated by the Virginia courts.

The common denominator in the current push to slow the county's growth is traffic.

In nearly every section of Fairfax, lines of bumper-to-bumper traffic begin forming at 6 in the morning and continue through the remainder of the rush hour. The cars back up again when work lets out. In parts of the county, the situation is not much better during nonpeak hours.

Many of the most severe problems are in the growth areas. In Centreville, three major cross-county arteries -- Rtes. 28 Sully Road and 29 Lee Highway and I-66 -- converge. Other congested areas include the Rte. 28 development corridor that stretches from Centreville to Dulles International Airport, the two-lane portion of Rte. 123 that snakes through Fairfax City, and, of course, the Capital Beltway.

The highways that run through Tysons Corner, the county's business center near McLean, have been ranked among the region's most congested.

Patricia Pitts moved to Fairfax's burgeoning Springfield District three years ago after spending time in San Diego and Newport, R.I. Although her husband has a good job at the Pentagon and her two young children have settled into their schools, Pitts said she is ready to move again.

"I don't think I've ever lived anywhere where the people are so angry behind the wheel of their cars," she said. "Traffic is bumper to bumper at 6:30 in the morning. My husband leaves for work at 6 a.m. just so he can beat it. And they county board members approve new developments that put more and more cars on the road."

Fairfax Supervisor Audrey Moore, the Annandale Democrat who has long been identified with the county's antigrowth forces, said that Pitts represents a segment of the population that county officials can no longer ignore.

"These people have lived in other places and they know that things shouldn't be this bad, and they know that with the proper planning, things wouldn't be this bad," Moore said. "They hold us responsible for it, and I don't blame them."

Fairfax County Planning Commission members are also feeling the residents' anger. Commission Chairman George M. Lilly said he and other members "are very conscious of the feeling out there." He said the commission and other county officials must "make more of an effort . . . to strike a balance between the interests of a healthy economic system and a good quality of life."

County Board Vice Chairwoman Martha V. Pennino (D-Centreville) pointed to a similar goal last week when she proposed, and the board sent to the planning staff for review, a one-year freeze on amendments to the county master plan. She said the delay would give the county time to implement critically needed road improvements.

"We're running out of time to cope with all this development," Pennino said a few days later. "We need time to catch up."

Pennino, who has supported much of the county's rapid buildup, aimed an uncharacteristically harsh attack at developers when asked about their objections to the board's new slow-growth posture.

"In many instances, developers are greedy," she said. "There are those who are sensitive and want what's best for the county. But there are others who are here to make a quick buck and are looking for an opportunity to bust the master plan. Well, we're not going to sell out."

A short time after Pennino issued her call for the year-long freeze, another supervisor, Supervisor Elaine N. McConnell (R-Springfield), urged the county to reexamine its policy of granting bonus densities to developers. She said the the system, which allows developers to build at greater density in return for providing roads or other public services, is being abused.

That kind of talk by county officials, combined with the groundswell of community activism, has heartened Pitts and others.

"I think people are finally fed up with taking it quietly," she said. The supervisors "are going to have a fight on their hands every time an issue comes up concerning growth. We're all ready to fight."

Although no one questions their resolve, the residents' slow-growth stance has come under heavy fire from development and real estate industry representatives.

"The planning process is being run by the Richard Korinks of the world," said an aide to a Fairfax developer, referring to the resident who led the drive against the Centreville proposal. "We're not fighting any more battles for the time being," added the official, who requested anonymity. He said most developers previously had won county approval for enough projects "to keep us busy for now."

Fairfax Supervisor Joseph Alexander (D-Lee), while acknowledging the residents' concerns, said the board overreacted in approving the limited development plans in Centreville and Vienna.

"I voted for it because the folks out there wanted it," said Alexander, one of the board's most avid prodevelopment members. "But I probably shouldn't have. I should have voted my convictions."

"Same thing in Vienna," said Alexander, who says residents in both areas were misled about the impact of the two developments. "I think we made a gross mistake there. I think the developers' proposals were far too great, but I think the plan we accepted will be bad for the area."

Alexander said he would support a move to reconsider those decisions.

Supervisor Davis said that residents have grown increasingly hostile at a time when the supervisors are doing more than ever to find answers to the county's traffic problems.

Noting that the county has appropriated nearly $200 million for highway improvements in recent years, Davis said: "There are rising expectations about the county and the state's ability to deliver. We're doing more and they're expecting more. Now we're going to have to deliver."