THE ROUGH-AND-TUMBLE battle between arch-enemies John F. Herrity and Audrey Moore for chairman of the Fairfax County Board of supervisors has not exactly been uplifting, though it has pointed up the dilemma of a prosperous county that has fattened faster than its arteries can handle. What has not materialized in this contest for us, at least, is any solid sense of a preferred candidate. So you will find no endorsement here. The disappointing caliber of the candidates for chairman -- and we include the challenges of independents R. Terry Robarge and James S. Morris Jr. -- makes unequivocally clear the need for an all-points search next time by both political parties for the kind of leadership and foresight that such a sophisticated, booming county requires.

As it stands, the edge in leadership abilities would go to Mr. Herrity, the edge in vision to Mrs. Moore -- and the responsibility for today's quality of life, good and bad, to both of them and everyone else on the board of supervisors over the years. Dispute though they do each other's past performances on the board, there is enough evidence in those events to find both Mr. Herrity and Mrs. Moore responsible for a share of the mess now troubling all residents. Mr. Herrity's indiscriminate eagerness to spread the welcome mat for developers clearly contributed to the horrendous pressures on the county's roads today, and Mrs. Moore's unrealistic resistance to highway, sewer and other projects necessary to meet inevitable growth has been just as damaging.

Though the chairmanship in Fairfax carries with it no special governmental powers -- the chairman merely exercises one vote of the nine-member board -- the winner does become the official voice of the county and does work with colleagues on the board and leaders of the other governments around the region. Mr. Herrity's gruff-to-crude style has not always shown the county in its best light, and Mrs. Moore's stubborn, uncompromising style also has generated understandable anxiety about her ability to get things done.

Business leaders in particular express a lack of confidence in Mrs. Moore's ability to maintain the boom that they have helped to underwrite or to respond to the transportation mess. There is room for uneasiness, too, in the failure of Mrs. Moore to articulate a specific agenda for producing the "controlled growth, carefully balanced with highway planning" she has vowed to support.

Yet Mrs. Moore's sense that much is is being done too fast and too carelessly in the county and that the "liveability" of the place needs more protection is right. With prosperity can come excess, and she is also right, we suspect, in her belief that whoever is returned to the board of supervisors this time will think differently about this issue. That would be one constructive outcome from an otherwise disappointing matchup.

If there is a bright spot in the county elections, it is that the voters do have some appealing decisions to make about who else should be on the board of supervisors. The opportunity to make effective statements against excessive growth and for transportation -- no matter who the next chairman turns out to be -- is far better in the district contests. Unlike the chairmanship race, these elections offer some thoughtful as well as practical candidates. Sure to return are two knowledgeable veterans, each more frequently allied with the chairman-candidate of the opposite party: in the Lee District, unopposed Democrat Joseph Alexander, who sides most with Mr. Herrity; and in the Mason District, Republican Thomas M. Davis III, who has been aligned on key issues with Mrs. Moore. Independent challenger Daniel Belsole is no match for Mr. Davis, whose performance makes him a strong prospect for political advancement.

In the Centreville District, Democratic incumbent Martha V. Pennino is one of the county's great resources. With experience, intelligence, humor and keen political instincts, Mrs. Pennino has led efforts for roads as well as for controls on growth. Her Republican challenger, Linda Douglas, is a bright light on the county scene who should be heard from again -- but Mrs. Pennino has what should be an indisputable claim on another term. In the Annandale District, the choice for the seat Mrs. Moore is vacating is between her former legislative aide, Democrat Sharon Bulova, and Republican Patrick Mullins. Both have been active in county affairs, but on the basis of her experience with the board, Democrat Bulova has an edge.

In the Dranesville District, Republican incumbent Nancy Falck's main challenge comes from Democrat Lilla Richards, with independent Robert L. Thoburn in a grudge run seeking to avenge his son's GOP primary loss to Mrs. Falck. Mrs. Richards' long record of civic activity, energetic attention to county issues and interest in being more accessible to constituents make her a refreshing replacement. In the Mount Vernon District, incumbent T. Farrell Egge's ineffectiveness and eagerness to please developers has embarrassed even some of his fellow Republicans. He is opposed by Democrat Gerald Hyland, a first-rate, community-minded candidate who lost the last time only because a third candidate split the vote.

In the Springfield District, voters deserve better representation and service than they have gotten from Republican Elaine McConnell, whose attention to the job has been anything but intense. Democratic challenger Toni Carney is a former county school board member who has enough familiarity with the responsibility and the issues to be a better representative of this fast-growing section of the county. And in the Providence District, Democratic incumbent Kate Hanley, elected last year to fill an unexpired term, wasted no time demonstrating a sharp sense of the office and a knack for getting along with diverse interests. Republican Myron Smith's challenge falls far short.