To preservationists, the neon "Pillsbury's Best Flour" sign over the Mississippi should be flashing "SOS."

The National Trust for Historic Preservation, a Washington, D.C., nonprofit, has added the Pillsbury A Mill complex to its latest list of America's 11 Most Endangered Historic Places. The annual list describes the A Mill as "in danger of piecemeal development" that could strip it of its "tremendous potential for re-use and rehabilitation."

It described the A Mill as "a masterpiece of industrial architecture" that was cutting-edge when completed in 1881.

The endangered designation doesn't carry any specific benefits such as access to funding. It's a publicity tool.

"It's a highly successful way to galvanize public attention," said National Trust spokesman Virgil McDill.

McDill said the A Mill was nominated by the city of Minneapolis Department of Community Planning and Economic Development.

Once one of the largest flour mills in the world, the A Mill complex is a collection of buildings across the Mississippi from downtown Minneapolis that includes the main A Mill building already designated a National Historic Landmark. The riverfront complex went back to the lender after plans for an expansive condo redevelopment called East Bank Mills fell through. Now, two other local developers -- Bloomington-based Doran Cos. and Dominium of Plymouth -- are picking up the pieces, working separately to buy the 8-acre site from Bismarck, N.D.-based BNC National Bank and build nearly 600 new apartments.

Doran is planning two new seven-story buildings with about 375 luxury apartments on the parts of the site that aren't historic and are mostly vacant. A few buildings will be razed for that project. Dominium is tackling the mill's historic structures, which it wants to convert into about 200 loft-style apartments with rents considered affordable to households at or below 60 percent of the metro area's household income. It's planning to tap the state's new historic tax credit, as well as the existing federal tax credit, for the project.

Royce Yeater, who heads the National Trust's Midwest office, said the A Mill was originally nominated for the endangered list before the current development plans emerged when there was fear the mill was going to languish. That threat has passed, he said, but there are still concerns that dividing the landmark in two, with different developers, will make it hard to create the well-integrated plan the riverfront site deserves. The developers have different philosophies, he said.

Owen Metz, senior development associate for Dominium, said his company has had several meetings with Doran and its architects and is "making sure that any plan that's put together is signed off by both groups."

"We're not going to piecemeal the historic part of it at all," Metz said.

Doran did not return a call Tuesday.

Other places on this year's endangered list include: Bear Butte in South Dakota's Black Hills, a sacred ground for more than a dozen Native American tribes that is threatened by proposed developments for wind and oil energy; Belmead-on-the-James, a 2,000-acre site on Virginia's James River that was once a slave-holding plantation and was turned into schools for African-American and Native American students; and the National Soldiers Home Historic District in Milwaukee, a collection of buildings that were once a refuge for veterans that the National Trust said is now on the verge of collapse.

For the full list of this year’s Most Endangered Historic Places, go to: www.

Jennifer Bjorhus • 612-673-4683