Should the proposed Western Bypass be designed to meet the land planning goals of local governments, or should localities adjust their growth management efforts to the route that such a new superhighway might take?

Local and state officials found themselves on the opposite sides of that question Tuesday as the Loudoun County Board of Supervisors weighed its formal statement to Virginia authorities regarding the much-debated highway. A narrowing of route options from three to one may occur by early 1991.

The supervisors tentatively plan to produce a formal board position at their next regularly scheduled meeting, July 3. This week, however, several board members made it clear they believe that local land planning issues should drive decisions about a Western Bypass, and not vice versa.

The Western Bypass, a multi-billion-dollar project proposed in the outer Virginia suburbs, and an Eastern Bypass on the Maryland side of the Potomac River, are being studied by the Vienna-based consulting firm of Bellomo-McGee.

Public hearings in Loudoun and elsewhere have been held in recent weeks. Ultimately, the consultant will make recommendations to the Virginia and Maryland state governments. One bypass, or neither, or both may eventually be constructed.

The so-called outer beltway is designed to siphon some traffic off of the Capital Beltway, particularly trucks and other long-distance Northeast Corridor traffic. All three alignments under study for the Western Bypass would pass through Loudoun County.

One would follow Route 28. Another would pass generally west of Goose Creek and cross the Potomac east of Leesburg. A third corridor also would pass west of Goose Creek, then cross the Potomac east of Point of Rocks. Tunnels or depressed roadbeds are under consideration in the Leesburg-Lucketts area.

On Tuesday, Virginia Department of Transportation planning engineer Richard C. Lockwood told the Loudoun supervisors that "development is coming to this region" and that the county board should act soon to preserve Western Bypass right of way and decide how many interchanges it should have on any of the three corridors under study.

"It's a planning issue for local jurisdictions," Lockwood said. He noted that on his journey to Leesburg Tuesday, he counted 77 trucks on Route 15, adding that this two-lane road will have to be upgraded regardless of whether, or where, a Western Bypass is built.

Board Vice Chairman Charles A. Bos (D-Leesburg) asked how the right of way could be preserved if not paid for up-front by the county government, adding, "How do we plan development for a highway . . . that may be a long time coming?

Commented Chairman Betty W. Tatum (D-Guilford), "I don't see how this board or any board in this area is going to find the money to buy the right of way . . . . Personally, I don't think we're going to be able to keep it down to one or two interchanges" in Loudoun, even in the event that construction money is found.

VDOT's Lockwood said no funding source has been found for the road, priced at more than $1.4 billion in today's dollars. But he said the 450-foot-wide right of way will only become harder to locate and more expensive to acquire if efforts are delayed.

"This is a road trying to serve too many masters," said Supervisor Betsey Brown (D-Catoctin), echoing comments of Supervisor Ann B. Kavanagh (D-Dulles) that the Western Bypass cannot properly serve local commuters, Dulles International Airport business and Northeast Corridor through traffic.

Supervisor Steve W. Stockman (R-Broad Run) said he believes that "Loudoun County can live with" any of the three possible routes, even though each has flaws. Previously, Supervisor Howard P. Smith (D-Sterling) and state Sen. Charles L. Waddell (D-Loudoun) have said the Western Bypass must be considered if it can alleviate local traffic congestion.

In 1988, the Loudoun board adopted a strong statement that it opposes "any proposal for a Western Washington Bypass that would traverse our County and cross the Potomac River."