Adolpho Victoriano (Al) Nodal, the 32-year-old executive director of the Washington Project for the Arts, has told the board of that artist-run museum, testing ground and theater that he intends to leave Sept. 1.

No quarrels or disaffections prompted his decision. Nodal says he is resigning "because it's time for a change."

"When I joined the WPA in May 1978, I made a promise to myself: I pledged that I would give it five years of my life. I have. The WPA is supposed to be receptive to new art and new ideas. It is not the sort of place where one builds an empire. It needs transfusions of new blood. It doesn't need my personality. It has one of its own."

The WPA, at 404 Seventh St. NW, has a full-time staff of 14 and manages to raise about $300,000 a year. Most of that comes from private sources. As administrator, fund-raiser, art world politican, entrepreneur and art scout, Nodal often works 14-hour days. His annual salary is $22,000.

He says he is "looking for a job, preferably in Washington." He will remain on the WPA board. A committee of its members is seeking his replacement.

"We are trying to find someone as good as Al," said Howard Fox, chairman of the board and a search committee member. Fox, associate curator for exhibitions at the Hirshhorn Museum, said, "It is not going to be easy. He's done a fabulous job."

Since Nodal replaced founder Alice Denney as executive director in June 1979, the WPA has more than quadrupled its budget. Nodal supervised the move from 1227 G St. NW, and in doing so helped renovate and open--for $40,000--what is, in effect, a large downtown museum for experimental art. A similar amount has been spent on the WPA's new theater which, though not as large as its performance space on G Street, is far better equipped.

Not all of the WPA's exhibits have been held within its walls. In the past three years alone, the WPA's Washington Art Site Project has arranged for the display--outdoors--of Bob Wade's "World's Largest Cowboy Boots," Jon Peterson's bum shelters, Alice Aycock's "Game of Flyers," a huge tornado made of junk and more than 40 other works of large-scale public art.

Nodal's first WPA project was the opening of a store for artists' books, Bookworks, now one of the largest and best-stocked of its kind.

He also has expanded the WPA's board. It now has 30 members, one third of whom are artists. "It is the best board I've ever worked with," says Nodal. Unlike most such institutions, the WPA spends $30,000 a year on direct payments to artists who exhibit there. In addition to expenses, they are given fees ranging from $300 to $1,000.

Nodal also was instrumental in organizing the National Association of Artists' Organizations, whose membership includes about 300 of the 400 "alternative spaces" now active in this country.

"There are three other projects I hope to get to before I leave," said Nodal. "The first is a book recording all the Art Site projects. The second is an experimental video program, and it's already under way. The third is the opening of the Atrium Cafe."

Born in Cienfuegos, Cuba, in 1950, the son of a boat builder, Nodal grew up in Miami and went to junior college there. He graduated from Florida State University, and then moved to California, where he took a degree in museum studies at San Francisco State University. His wife, Joy Silverman, a former WPA assistant director, now lives in Southern California where she directs LACE, Los Angeles Contemporary Exhibitions.

"Al is a wonderful person," said D.C. City Council member John A. Wilson. "He's patient and he's smart and he's done a bang-up job."

"Nodal has rhythm, presence, energy," said former Washington-art-world-everything Walter Hopps, now director of the De Menil Collection in Houston, and a member of the WPA board. "No one else has built here an institution that shows how diversified the media of the visual arts can be. He really believes in a working community of artists. Not all his shows have been of stop-your-heart quality, but they've never been sterile."

Board chairman Fox says the WPA hopes to select a new director before May. The search committee includes Fox, Hopps, Terry Braunstein, Maida Withers, Carolyn Peachey, artists Sam Gilliam and Rockne Krebs and attorney James Fitzpatrick.