Celebrating the Downfall of the Berlin Wall : Concert: Former Pink Floyd leader Roger Waters will take his epic ‘The Wall’ to the source . . . East Berlin.

It took the Wall’s coming down to get Roger Waters to put “The Wall” back up.

The former leader of Pink Floyd had long sworn that he would never again mount a concert production of his epic concept piece about dehumanization and alienation. “The Wall” has been performed only 29 times, including the five-show debut at the Los Angeles Sports Arena in 1980, and its last performance in London in 1981.

Even after Waters left the group in 1983, fans hounded him to do the show again. But Waters was adamant.

“As the piece was written as an attack against the inherent greed of rock ‘n’ roll in stadiums, it would be extremely stupid, notwithstanding very hypocritical,” the genial Englishman said while sitting in the courtyard of a Beverly Hills hotel recently.

But last year, one writer for a show business trade magazine would not take no for an answer.

“So I said, ‘OK, you have me, “ Waters, 47, recalled. “ ‘If they ever take the wall down in Berlin, I’ll put it on there as an act of celebration of that bit of freeing of the human spirit.’ End of story.”

Then, just as in the climax of the “Wall” concert, the Berlin Wall came down last Nov. 9. So on July 21, Waters will perform “The Wall” on Potsdamerplatz in East Berlin, right next to the Brandenburg Gate, on a scale about as massive as they come.

More than 150,000 people are expected to attend the globally televised concert, which will feature a cast of perhaps 300 (including the Berlin Philharmonic Orchestra, the Chorus of the Soviet Red Army and several guest rock stars), and giant inflated characters from the story. And, of course, there is the wall itself, a 60x600-foot structure of cardboard bricks that is erected in front of the musicians as the show progresses.

In truth, Waters had agreed in principle to stage some version of “The Wall” before the Berlin Wall came down. Last September he was visited by a representative of the World War Memorial Disaster Relief Fund. The fund, a new venture set up by British World War II hero Leonard Cheshire, needed an event to inaugurate its five-year campaign to raise $800 million for assistance to disaster areas around the world.

“Leonard is trying to encourage the old forces of apparently opposed ideologies . . . to cooperate across international boundaries in the face of natural disasters, so that American soldiers can go into Armenia and dig children out of the rubble,” Waters said.

Though mindful of both his own promises and the potential problems of such a charity event, Waters--whose father was killed in World War II--agreed to meet with Cheshire, and soon agreed to stage the show, donating his time and publishing royalties from a live album to come from the concert.

“We talked about a site and he said, ‘What about Berlin?’ I said, no, that’s the one place we cannot do it, with the way things are changing in Eastern Europe. I said that it would be impolite and impolitic to go shout ‘Tear down the wall’ at the East Germans right now. So we talked about the Grand Canyon and the Gobi Desert and Red Square. . . . Wall Street was my favorite. The thought of closing New York for a day just to put on a show for charity is really beyond the pale. . . .

“Then Nov. 9 happened and they took down the wall and we got on a plane the next morning and flew to Berlin. . . . We peeked through the wall and saw this enormous piece of land, and I said this is where we’re going to do this show--if we’re going to do it at all.”

For all the grandiosity of the planned show, there is one moment Waters hopes will happen. “Now that I’ve got these Russians that are going to be on stage singing ‘Bring the Boys Back Home,’ maybe I can use that as a lever to move some of the entrenched politicians in Whitehall (to let us have British soldiers join the chorus),” Waters said.

Waters believes such a collaboration would capture the spirit of both “The Wall” and the international relief efforts the Memorial Fund is designed to tackle, as well as the changes symbolized by the Berlin Wall’s demise. But he’s less than hopeful of its fulfillment.

“I need them desperately to be in the show, standing on stage in their British uniforms with a big orchestra and chorus, and with any other soldiers from any other armies I can get to do this. But the fact that it’s Margaret Thatcher (who has to approve) makes it very difficult.”

One wall still stands solid in Waters’ life: the barrier between him and his former bandmates. In 1987, Waters filed a lawsuit in England to force the retirement of the name Pink Floyd, which he co-founded in 1966. But he lost the suit, and guitarist David Gilmour, drummer Nick Mason and keyboardist Richard Wright are still allowed to perform and record under that name. In an ironic twist, that band put out a live album in 1988--eight of whose 15 songs were written or co-written by Waters.

“If I could prohibit that I would, but I can’t,” he said resignedly. “Anybody can use anybody’s songs, that’s fair enough. What really galls me is them using songs from ‘The Wall’ in stadiums.”

Waters also freely acknowledged that his former mates sold more albums with their 1987 “A Momentary Lapse of Reason,” than he did with his “Radio KAOS” of the same year. He also admitted that at the time he was very angry the band was getting more attention than he was, a fact made clear in interviews from the period. Now, he seems more resigned to the legal decision.

“(Pink Floyd) is a very powerful brand name, as we have seen,” he said. “It could be that after this thing is over a great number of people around the world may think it was a Pink Floyd gig in Berlin. And that’s something I have to live with.”