The value of land around operating Metro stations throughout the Washington area has increased at least $2 billion since the first subway train slipped out of Farragut North five years ago, according to a new congressional staff survey.

Beyond this dramatic jump in land values, the cost of housing and office space near the stations is generally rising, but how much is attributable to Metro alone is conjectural at this stage.

The survey's findings seem to bear out the argument of many who had pressed for years to build Metro -- that a subway system would stimulate economic growth and revitalization, particularly downtown. Similar arguments have been heard more recently from those favoring the convention center now under construction in Northwest Washington.

Spurred by its surge in sales after linking up with Metro Center at its downtown store, Woodward & Lothrop is planning a $150 million retail, office, and hotel complex for the entire square block just north of the store; Hecht's is planning to move into a similar massive complex across the street, and Bloomingdale's is talking to the mayor's office about locating a third metropolitan area store downtown near Metro.

James McCullagh, regional vice president of Bloomingdale's, said that so far they'd found that "real estate and location are very tough in terms of the size of store we want to build." But the company was continuing to examine opportunities because downtown Washington is going to be an unbelievably exciting place in the next few years."

The congressional staff survey, which is confined to the areas immediately surrounding stations already opened, found that Metro has:

Increased the value of downtown commercial land in the District of Columbia by at least $1.6 billion.

Increased the value of residential land in Northern Virginia by at least $81 million.

Increased commercial land values around the Silver Spring station by $31.2 million.

The one exception the study found to the pattern of significantly rising values was in Prince George's County, where "no noticeable Metro impact" was perceived in residential land values and only $5-to-$7 million was added to the light industrial and commercial land adjacent to the New Carrollton station.

The study, which took 2 1/2 months to conduct, was carried out by the staff of the House subcommittee on the city at the request of Rep. Henry S. Reuss, (D-Wis.), chairman of the committee on banking, finance and urban affairs. The study has not yet been released.

Reuss' special assistant, Walter Rybeck, who directed the survey, said his three-member team found that Metro had varying effects on values. For example, he said, "In Arlington, people have paid a $10,000-$15,000 premium for housing near Metro, even if the neighborhood was inherently less attractive than another area."

In Prince George's County, however, "realtors said there was impact, but we couldn't find it." He added that although the team did not formally survey stations yet to be opened, "we found that Bethesda seems to be ahead of schedule with buyers paying a premium for the coming Metro station."

A clear illustration of what being near a Metro station can do for prices is a comparison between two condominium buildings in suburban Virginia which are of similar vintage, surroundings, construction quality and desirability, with the exception that one is up the street from a Metro station and one is nowhere near Metro.

The building near the Orange Line's Virginia Square station is Tower Villas. The other building is Skyline Towers, located on Route 7 at Bailey's Crossroads in Fairfax. Combined average prices of one-, two- and three-bedroom units in the two buildings showed that purchasers paid $107,450 at Tower Villas and $88,900 at Skyline Towers.

Another example concerns the Pentagon City station. Town house buyers last year paid a mean price of $106,500 for units in the South Hampton development, located 1,000 feet from the Metro exit, while buyers of virtually identical town houses in the Concord Mews development, two miles from the nearest station, paid a mean price of $94,200.

And at the Ballston station in Arlington, town houses a short walk from the station are selling for $150,000 while those a few miles away, in a somewhat more attractive neighborhood, are going for $110,000-$125,000. Appraisers, assessors and realtors say this is the difference -- or "Metro premium" -- area residents are willng to pay for convenience to the subway.

"I consider Metro a very determining factor [on prices], more so in the peripheral areas," said Giuseppe Cecchi, a major condomimium developer who concentrates on Northern Virginia. "It affects commericial prices in the central city and residential prices in the outlying areas. There are also in-between areas, like Rosslyn, where it affects both."

Using the most conservative real estate formulas available, the congressional survey found that "a minimum of $2 billion in land values has already been added to the existing land value base." The computations involved, for example, placing rental premiums of $2 a square foot, for office space in buildings atop or immediately adjacent to Metro stops in downtown D.C. The $2 premium was applied for downtown blocks that contained a Metro exit or that were directly across the street from an exit; adjoining blocks were given $1 premiums.

Another calculation comprised placing a premium of $9.50 for each square foot of living space in the Tower Villas condominiums.

Rybeck said in an interview that a number of realtors and developers had told him that in same areas, particularly in downtown D.C., the determinations could be doubled. This led Rybeck to conclude that added values may be as high as $3.5 billion.

Reuss said in an interview that he ordered the survey because of his concern that $2.7 billion in federal funds had already been contributed to Metro. "I wondered if it is fair to charge the taxpayers when Metro appears to be doing little to recapture the enhanced values of properties, it is affecting."

Addressing this question, the survey said that taxpayers "created" the $2 billion to $3.5 billion and that taxpayers should be gaining tax relief from these riches." Instead, the survey said, " the biggest share of these new values is going . . . to the people who were lucky enough to own land within easy access of Metro stations."

The survey recommended that these circumstances be altered by having Metro and local jurisdictions extend the few joint development projects they've entered into; buy up land around new stations for resale or rental and charge property owners in the enhanced areas "for their new advantages."

Henry Cord, director of Metro's real estate office, said that he had not yet seen the congressional survey and that although it would be premature to comment on it, Metro considered recapture of income from rising land values "a regional matter."

"It's not locked in to any one jurisdictional method," Cord said. "Local jurisdictions control development -- that's the key. We're looking down the road to encourage local jurisdictions to stimulate growth and quality development. Our role is basically to be a catalyst."

It's beyond doubt that money is being made by investors, developers, speculators, realtors, home owners and others around Metro stations. But the effects are uneven, according to dozens of interviews conducted by The Washington Post in the last two weeks.

Cecchi, the condominium developer, reported stunning success with the first part of a high-rise condominium complex, Montebello, that he is constructing adjacent to the Huntington Metro station in Alexandria: all 253 units, ranging in price from $59,000 to $131,000, were sold out from a waiting list of 1,600 without a single advertisement, "while the building was still in the ground."

Cecchi said he attributed this achievement to two factors -- "its being located next to the Metro parking lot and atop a beautiful hill overlooking the entire area." Cecchi said he didn't know how much effect the easy access to the station had on prices, but "sales would have gone slower, I'm sure. I'd still be selling." The station is due to open late next year.

"The fact that it sold so fast shows me that people will pay a Metro premium and I'll get that on the second building," he said. "Metro also helps me overcome a soft market; it's like having an office building at Connecticut Avenue and K Street -- it's prime."

Cecchi said he has just filed a plan with Arlington County to build 500 deluxe condominiums in Rosslyn, "overlooking the river and the Lincoln Memorial . . . and just three blocks from the Metro station."

Dave Spires, a realtor with Shannon and Luchs in its Alexandria office, said "we've already seen a rise in prices" around the Huntington station. "There's a lot of speculation. In '76, semidetached, smaller houses off Huntington Avenue were going for $32,000. Now, they're $65,000-$75,000 and selling much faster than they did in '76."

Other realtors observed a dramatic rise in prices and prestige in outer Arlington and Falls Church. "We're getting a tremendous number of relatively high-priced -- $150,000-$200,000 -- town houses under construction," said Dick Frank, president of the 96-member brokers council of the Century 21 realty chain.

"This is a big chance to the area and Metro is a big part of the influence," Frank said. "People feel they have an easy trip to the city along with a quality house.Two years ago you couldn't sell a $200,000 town house in Falls Church. Then, $80,000 to $90,000 was the outer limit." The Orange Line's extension through Falls Church and beyond to Vienna is officially scheduled to open late in 1985.

The picture in Montgomery County seems about as bright, but perhaps less widespread, with much of the optimism for future growth pegged to the extraordinary success of a single condominium complex, the Grosvenor Park, which is linked to the Grosvenor Metro station by a pedestrian tunnel beneath the Rockville Pike auto traffic.

With the station not scheduled to open until late 1983, the Grosvenor sold out four years ago in a three-month period. It has been logging a spectacular appreciation of more than 40 percent a year ever since, which several brokers attributed to original prices being at least $10,000 too low. "I guess the prices were right," said Nick Johns of Shannon and Luchs' Rockville office, "but the future Metro station is right across the street."

"Of course, convenience always adds value," said William Wise, a real estate apraiser who works out of his home in Rockville and who does about 1,000 appraisals a year, mainly for banks considering granting loans. "The average condominium price is up," he said, "because condos are more affordable than private houses, rather than because of Metro. Nobody in Washington can tell for sure what Metro is doing."

Many realtors in suburban Maryland and Virginia said that potential buyers almost always asked about access to a Metro station, but that this wasn't necessarily reflected in the prices they were willing to pay.

In some in-town neighborhoods, Metro hasn't had much effect on prices. "People want to move to Cleveland Park because it's Cleveland Park," said Gary Czerner, manager of the Legum and Norman realty firm, which specializes in that costly Northwest neighborhood characterized by large, Victorian houses. "They don't ask about Metro, but it's an additional factor, like good schools, intellectual neighbors, good restaurants."

Konrad J. Perlman, acting deputy chief of the D.C. Department of Housing and Community Development's planning and research division, said he found that generally, "residential costs within a 15-minute walk of a station are high. Beyond that, not."

The important question to be asked in the District, Perlman said, was "Will Metro affect prices in places where it hasn't already reached -- for example, east of the [Anacostia] River?"

Prof. Dorn McGrath, chairman of the department of urban and regional planning at George Washington University, said the Fort Hunt area outside Alexandria had already become "a gold mine directly related to Metro" and that a similar evolution could be expected in the historic Anacostia-Uniontown area of the District.

As to Prince George's County, Earl Merkl of Long and Foster's area office said that he attributed a 10 percent increase factor to the opening of the New Carrollton station. "There'd been an 8-to-9 percent rise each year until last year, when it rose 19 percent," Merkl said.

He said this applied to houses within a five-mile radius of the station. "These houses were selling in the high $50,000s. Now they're going for $65,000-$75,000. They're frame, three-four bedrooms, 15-25 years old, in mixed-race neighborhoods, nice residential neighborhoods."

Merkl said the buyers of these houses tended to be young families from out of the Washington area whose top requirements, in order of importance were, "location, appreciation because they mostly plan to move away, Metro schools, entertainment and shopping."

This upbeat assessment differed from the findings of the congressional survey. And Barry Hill, an appraiser with the firm of Thomas J. Owen, who lives in Cheverly, said his own findings were that values "appear to be rising, but sales velocity is dropping. I can't determine what's due to Metro, but certainly Metro isn't having an adverse effect."