THOUGH IT HAS DONE so much good for this city's children and adolescents, the YMCA of Metropolitan Washington is not immune from mistakes--and it has made a big one in the way it has just abruptly shut down the Anthony Bowen Y in the heart of Shaw. For those who may not be familiar with this facility at 1816 12th Street NW, the Bowen Y has been a critically important center of constructive activity in a neighborhood where the alternatives for kids are less than uplifting, to say the least.

But the YMCA board has cited safety factors and fire code violations as reasons for closing this 73- year-old building that has been home for the first black Y in the country and one of but two citywide that have been available at affordable costs for young people. Costs for repairs have gotten out of hand, the board says, noting that the YMCA is committed to building a new facility in the area as a matter of the "highest priority."

That's all fine, so far--and someday the young of Shaw may be flocking to a dazzling new center with the finest equipment. It may even be half as snazzy as the new multi-million-dollar building at 17th Street and Rhode Island Avenue NW, where a slightly different clientele of adults pays initiation costs and annual membership fees on scales up to several hundred dollars. But must the present Bowen facility be bolted shut for however long this promised facility takes to move from drawing board to reality?

If the Bowen Y is all that unsafe, D.C. Recreation Department director William H. Rumsey--who has spent a lifetime working with and for the young people of the city--is out of character in disputing the seriousness of the problems at Bowen and in urging that it be kept open. Besides, surely officials of the Y could meet with top officials of Mayor Marion Barry's administration, including experts from the fire department, to agree on acceptable conditions for operating Bowen until there is a new facility.

Basketball, arts and crafts, games and other activities--organized or self-generated--are far preferable to hanging out in the presence of drugs, prostitution and all the unattractive pastimes that can substitute for the Y's popular recreational activities.

We consider the Bowen closing an emergency--and if the YMCA will just respond to it as well as it has in the past to this city's youth, it will find a way to maintain its constructive presence in Shaw without a damaging break in service.