Maybe the play is going to be good, maybe not. If you weren't full of hope that it might be, you wouldn't have bought a theater ticket.

But you know that the orange drink sold at intermission is going to be terrible - and yet you buy it. There isn't anything else.

Orange drinks, coffee, apple cider, and occasionally beer and wine are the only drinks available in Washington theaters, except from the Kennedy Center, which has special permission to sell cocktails. But now the D.C. City council has voted to permit all the professional theaters to sell liquor and it seems likely that legislation permitting this soon will be enacted.

Arena State sees this as a possible major addition to its income. The National Theater will continue to sell orange drink and fruit punch, on the grounds that liquor isn't worth the double. And other theaters have neither rejected the opportunity or are considering it very cautiously.

Ken Bloom, associate producer of the New Playwrights' Theater, went so far as to say it would depend on the play. "For a cabaret show, it would be nice to have liquor, but for some shows we don't want to get the audience drunk," he said.

Roger Stevens, chairman of the Kennedy Center, said that the income from liquor sold there "doesn't amount to much - it's very disappointing." The Center gets 10 per cent of what the Canteen Corporation grosses by selling champagne for $1.50, cocktails for $1.75 and premium liquor or cognac for $2.

At that, he said, it is more practical to sell drinks there than in an ordinary theater, such as the National. "When we have three staggered intermissions, we don't keep bartenders sitting around doing nothing," he said of the Center. "But the National - people can't even move in the lobby there. There's not enough room. We have no plans whatsover to sell drinks there. You can't make any money out of keeping a bar open for 15 minutes. Lots of theaters take it out after they get it."

But Tom O'Connor, Arena Stage spokesman, said it should "help substantially. We make a tiny bit on small concessions, but liquor is a major concession. We need every possible source of income we can get, since the main thing - what we're putting on stage - doesn't do it."

Arena now sells coffee (40 cents), soft drinks (50 cents) and champagne ($1.25) at its main and Kreeger theaters, and beer (1.25) and wine ($1.50 a carafe) at its old Vat Room. As soon as legally possible, it will turn the Old Vat Room into "a real cabaret" and serve cocktails at the other theaters.

"The trick is to turn it over quickly," he said. There will be prepoured drinks, and mixers that the purchasers can add for themselves.

The Folger, which now sells cider (50 cents) wine ($1) and beer (78 cents), hopes to add liquor to be sold before the plays, as well as during intermission. "But we can't lengthen the intermissions - our plays run long," said business manager Mary Ann de Barbieri.

Ford's Theater has decided it simply doesn't have the space. Bark Alley and ASTA are thinking it over, and the Washington Project for the Arts is not considering the idea.