Virginia highway officials, hard hit by reduced tax revenue resulting from motorists' descreased gasoline consumption, today approved cutbacks totaling $37 million in the state's road-building program.

Fairfax County, the state's largest and most congested suburban jurisdiction, will be the hardest hit, although a statewide breakdown of the spending cuts was not immediately available.

Several major projects that county officials considered top priorities will have to be postponed, including further widening of the county's traffic-choked Rte. 1 commercial strip and a critically needed new interchange in the bustling Tysons Corner area.

The State Highway and Transportation Commission gave tentative approval to a revised 1979-80 program totaling $328 million -- nearly 10 percent below the $365 million figure officials originally slated for the present year. It also approved a preliminary 1980-81 budget of $354 million.

State officials blamed the cutbacks on reduced gasoline consumption, which in Virginia has fallen nearly 10 percent in the past year, and noted that other states face similar problems.

In Maryland, where state gasoline tax revenues also make up a significant part of highway-building funds, revenue from the tax was down almost 7 percent during the first 10 months of the current fiscal year as the price of gasoline rose steadily and conservation became more attractive to motorists. oNo decision has yet been made whether to cut back on Maryland highway construction.

According to statistics compiled by the National Governors' Association, at least 27 states have either increased or are considering increases in gasoline and other road taxes to finance lagging construction.

"In a number of these states, construction has ground to a complete halt," said association spokesman Joseph McLaughlin.

Virginia's General Assembly, after a prolonged and bitter struggle earlier this year, approved a 2-cent increase in the state's 9-cent-a-gallon gasoline tax effective July 1. But even with the increase state highway officials said today their preliminary projections put the state's 1980-81 road building programs at $11 million below what they had originally hoped to spend this year.

"The end result is we're trying to spread the limited resources as far as possible," said H. R. Perkinson Jr., program management director for the state Department of Highways and Transportation.

Northern Virginia officials, who stand to lose at least $1 million in primary and urban road construction in the coming year, reacted angrily to the department's new allocations. They renewed longstanding complaints that the Washington suburbs are seriously shortchanged in state highway allocations.

"Funds have got to come to Fairfax from other areas of the state," said Fairfax County Board of Supervisors Chairman John F. Herrity. "I'm not in favor of taking money from urban areas but in some of those (rural) places you have four-lane turtle crossings."

The eastern part of Fairfax County was hardest hit by the commission's allocation. Some $2 million was taken from the next phase of the four-lane construction of Rte. 1 toward Fort Belvoir, and only $100,000 was provided for the four-lane building of North Kings Highway, which will be a major Metro access when the Huntington station opens in 1982.

"I'm very upset," said Supervisor Joseph Alexander (D-Lee), whose district would be served by both improvements. "We have not been able to influence the highway department in any major way."

Like most states, Virginia finances its road-building program with gasoline taxes collected on a cents-per-gallon basis. In recent years, inflated construction costs combined with increased gasoline conservation due to more fuel-efficient cars and higher prices have gradually eaten away at the state program.

States are also being threatened with possible cutbacks in federal highway funds, which provide 75 to 90 percent of the money for interstate, primary and urban roads. Virginia Highway Commissioner Harold King said today he is optimistic that the federal government will supply enough to meet the state's projected budget.