Efforts to improve bus service in the District have been hamstrung by frustrating delays in finding an appropriate site for a new bus garage in Southeast or Southwest, the city's transportation director told a congressional committee yesterday.

The federal government is largely responsible for the delays because it has impeded the city's attempt to negotiate a site for the new facility, needed to improve maintenance of buses that operate in the city, testified Thomas M. Downs, D.C. director of public works and transportation.

"Until federal concern is translated into positive federal action," Downs said, "unreliable, inconsistent bus service will be the norm and not the exception in the District of Columbia."

The House District Committee hearing, chaired by D.C. Del. Walter Fauntroy, was called after the publication of reports in The Washington Post showing that the worst Metrobus routes are in the District and the best generally in the suburbs.

Downs and Richard Page, general manager of the Washington Metropolitan Area Transit Authority, said they have virtually given up on getting the city's preferred site, a federally owned tract adjacent to Fort McNair, because of Army demands for an environmental impact statement that could take years to complete.

Downs particularly faulted Maj. Gen. Jerry Curry, commanding general of the Military District of Washington, for opposing the facility and demanding the environmental impact statement. Curry had said a bus garage would be harmful to the historic and esthetic nature of the fort and detrimental to the living environment of soldiers based there.

But Downs charged that Curry actually was more concerned about the esthetic sensibilities of the many high-ranking military officers living there on "Generals Row." "I think we have stumbled onto a sensitive area," he said. Curry's expressed concerns "are more a tactic of delay . . . rather than legitimate concerns for the integrity of the fort," Downs said.

Curry adamantly denied this, saying through a spokesman that the comment about Generals Row "is a complete distortion of the facts and patently untrue and Mr. Downs knows it." Generals' homes are on the opposite side of the fort from where the proposed garage site is, the spokesman said.

The Smithsonian Institution had requested that the General Services Administration give it the site for storing building materials and exhibits, a use Curry has not opposed.

But Fauntroy said yesterday he had it on good authority that the Office of Management and Budget, which had to pass on the Smithsonian's request, had turned them down. An OMB spokesman said he could not confirm or deny that account.

The city would be next in line for the surplus land, but the two or three years required to do the requested environmental impact statement would be prohibitive anyway, Downs said.

WMATA therefore is looking at two privately owned sites, Page said. One, owned by Pepco, is next to the preferred site, and it would cost an estimated $25.5 million to buy the land and build there. The other, owned by Washington Gas and Light, is in Southeast at the 11th Street bridge and could require as much as $60.6 million for the project.

The city had hoped to spend a total of about $17 million on the new garage.