Have you tried to find a gas station downtown lately?

Let's put it this way, if you drive into downtown make sure you have a full tank.

Gas stations, both full-service and self-service, have become a vanishing species in and around downtown since real estate prices took off in the late 1970s in the area from North Capitol Street west to Rock Creek Park and from the Mall area north to P Street NW.

There are now only 15 gas stations located in that area according to documents supplied by the city government. City officials think there were triple that number five years ago.

For years there was an Esso station at 18th and L Streets NW. The new Washington Square office bulding now occupies the entire block. The same thing happened to the long-time Gulf station at 14th and L and the Esso at 12th and E Streets NW, just to name a few.

The entire K Street corridor from North Capitol Street to the Whitehurst Freeway is served by two gas stations, and both of them are east of Seventh Street.

Only one gas station survives along P Street NW between First and 23rd Streets.

There are no gas stations located on Massachusetts Avenue from the Capitol to Rock Creek Park, although motorists will find three stations on upper Massachusetts Avenue within a block of the District boundary's with Montgomery County.

In fact the number of gas station is dwindling throughout the city; it is just more dramatic in downtown.

The Service Station Dealers of America, an association of service station owners, recently reported that there were 300 gas station operating in the city in 1979.

That number has now tumbled to 160, according to the association.

City officials agree that there are fewer stations but say they don't agree that the number has been reduced by almost 50 percent.

Instead, they report that there were 268 stations five years ago and 208 now.

Of the existing stations, about 120 offer a full line of services plus self-service lanes. There are only 34 stations that do not offer self-service lanes.

"You can count on two hands the number of full-service stations left within a two-mile radius of the White House," said Vic Rasheed, director of the Service Stations Dealers of America.

"Full-service stations have been reduced drastically," he continued.

"Many people in the city who were friendly with a local station have no one to call now when they have car problems."

American Automobile Association spokesman Tom Crosby said "it's possible" that the AAA's 12 percent increase in membership in the District during the past two years resulted from the reduction in gas stations.

High real estate prices in and around downtown have pushed gas stations to the fringes of the city. As a result, clusters of stations are found along the upper stretches of Georgia Avenue NW, Minnesota Avenue NE, Pennsylvania Avenue SE, and other heavily traveled thoroughfares leading to the suburbs.

While the office building boom in downtown is blamed for wiping out stations there, Rasheed blamed the city's gas tax and the required use of vapor-recovery nozzles on gas hoses for the reduction in gas stations citywide.

The District levies a 15.5-cent-a-gallon gas tax compared to 13.5 cents a gallon in Maryland and 11 cents a gallon in Virginia.

In addition, Rasheed and other gas station owners have long argued that the vapor-recovery apparatus makes gas hoses unwieldly. The U.S. Environmental Protection Agency have required the special nozzles in only the District and California because of the high air pollution rates.

"All the dealers are crying because so many customers don't like to buy gas in D.C. because of the nozzles," said Myong Kim, whose Texaco station near 10th Street and Pennsylvania Avenue SE has suffered a "25 percent drop in business" in recent years. "People know it's also cheaper to buy gas in Maryland or Virginia. I'm working 14 hours a day just to maintain my business," Kim said.

Added George Harris, whose Amoco station at 33rd Street and South Dakota Avenue NE is located three blocks from the Maryland line. "Mostly everybody's going to Maryland for gas because D.C. keeps raising their tax rates," Harris said. "Half of my pumps are self serve, and 75 percent of my customers come for that. With the full service alone, the business would die."

But not all stations are feeling the pinch. "Business here is relatively steady," said Leon Miranian, owner of the full service Watergate Exxon in the 2700 block of Virginia Avenue, NW. "At one time, paying two or three cents more a gallon in the District was a problem, but we've built up our customers over the past 15 years. Self service is here to stay, but no matter what, people will require general repairs."

Five years ago, the District sold 183 million gallons of gas at a tax rate of 10 cents per gallon, and collected $19.6 million in revenue. This year, gasoline sales dropped by nearly 25 million gallons, but the city's gas tax revenue grew to $24.5 million.

"Sales don't affect revenue," said Bill Cook, a high-ranking official in the city's Department of Finance and Revenue in charge of economic and tax policy.

The city has followed a national trend with a decrease in gas consumption. But city revenues have not suffered because "rates are adjusted by the Consumer Price Index and the tax is already collected from the oil companies at the point of importation," Cook said. "Based on the CPI, the national decrease in consumption means we just adjust our tax rates," he added.

Cook denied that gasoline sales are lost to Virginia or Maryland, "since the tax burdens there are commensurate with what we've got."