Viewed from a window of the Smithsonian Institution Building or the Smithsonian Castle an umbrella clad pedestrian makes their way by the Enid A. Haupt Garden on Wednesday September 28, 2016 in Washington, DC. (Matt McClain/The Washington Post)

The little guys won a battle, but the war is far from over.

The Committee of 100 scored a largely symbolic victory Thursday morning when a Washington agency voted to include the Smithsonian Quadrangle as a historic district in the D.C. Inventory of Historic Sites.

The designation does not grant legal protections to the district’s four buildings and the Enid A. Haupt Garden, but the D.C. Historic Preservation Board’s approval raises public awareness of an area that is threatened by future development, according to preservation supporters.

“There’s a moral issue,” Committee of 100 Trustee Pat Tiller said. “We’re trying to shame the Smithsonian into doing the right thing by bringing public attention to it.”

Civic organizations, garden enthusiasts and historic preservation groups have spent more than two years fighting the Smithsonian’s plan to redevelop the area around its historic administration building, known as the Castle. Designed by Bjarke Ingels and unveiled in 2014, the master plan focuses on one of the most historically significant areas in the city, the strip along the southern edge of the Mall from the Freer Gallery of Art to the Hirshhorn Museum.

The area includes the Castle, the Arts and Industries Building, both National Historic Landmarks, the Freer Gallery of Art, which is listed on the National Register of Historic Places and the mostly subterranean Quadrangle Building, home to the National Museum of African Art, the Sackler Gallery of Art and the Dillon Ripley Center.

Ingels’s plan calls for improved visitor amenities and better flow between the buildings, as well as upgrades to mechanical systems and new entrances for the museums.

Sharon C. Park, the Smithsonian’s associate director of architectural history and historic preservation, submitted written testimony objecting to the Committee of 100’s nomination. But appearing before the board, she reversed that position.

“The Smithsonan is not prepared to oppose the listing of the local landmark. but we feel very strongly that the nomination is incomplete,” she said before inviting the Committee of 100 officials and D.C. historic preservation officers to “visit the Smithsonian archives to further research and expand the information in their nomination so that it can be clarified.”

She said the Smithsonian would work with city officials to revise the nomination for listing to the National Register of Historic Places — a national designation — but she stopped short of pledging support for that effort. “We are neutral on it,” she said.

Alexandra Graubert, grandniece of Enid A. Haupt, the garden’s donor and namesake, testified in support of the nomination, as did three former Smithsonian employees who were involved in construction of the quad and the securing of Haupt’s donations, which included a $3 million endowment in the 1990s to maintain the garden in perpetuity.

“The essence of a garden is change,” Graubert told the board. “But the ideas and essential designs can remain the same.”

The Smithsonian last year commissioned its own report about the significance of the Quadrangle Building and found it was not eligible for historic designation. The Committee of 100 filed its nomination as a result.

“The Smithsonian administration is totally ignoring both the historical and present-day importance of that Quadrangle and the garden,” said Richard Guy Wilson, professor of architectural history at the University of Virginia. “The garden provides one of the few and great places where one can stop and relax.”

As required by the federal historic preservation law, the Smithsonian has held meetings intended to explain its needs and hear feedback from the community. The project has costs of $4.6 million, including payments for architecture, consulting and engineering fees.

Typically quiet and collaborative, these events have been characterized by angry outbursts and charges against the Smithsonian of misinformation and lack of transparency.

The tension stems from lingering mistrust of the Smithsonian, according to several preservationists. Only last year, the museum ignored repeated complaints about the lighted signs it erected outside the newly renovated Renwick Gallery, signs that were not vetted by federal agencies.

“The Smithsonian has always had a little bit of a history of not wanting to be subject to too many rules and such,” said Tersh Boasberg, former chairman of the D.C. Historic Preservation Review Board, who teaches preservation law. “There’s a bit of ‘We are the Smithsonian Institution. We know better than anyone else.’”

peggy.mcglone@washpost.com