In late 1976, Pink Floyd arranged to have a pig-shaped helium balloon the size of a double-decker bus raised above the hulking Battersea Power Station on the Thames in London for a photo shoot. The balloon escaped its tether and the pig floated away, eventually landing in a distant pasture and badly frightening some cows. But the image of pig and brooding power plant was committed to film, and later graced the cover of the group’s album Animals.

So when talk of demolishing the station arose in 2005 (it hadn’t been running since 1983), Pink Floyd fans rushed to the barricades. “You don’t dare to touch my chimneys,” one declared on a fan site. Demolition would be “an act of vandalism,” wrote another. “Every effort should be made to save Battersea.”

The monumental structure, designed by Sir Giles Gilbert Scott and built in stages beginning in 1929, is now safe from the wrecking ball. After more than a quarter-century of debate, London’s mayor signed off on a plan late last year that puts the iconic brick structure and its smokestacks at the center of a development of mid-rise apartments, offices, and entertainment venues. The project encompasses almost 40 acres and will cost nearly $9 billion.

Across the Atlantic, in Brooklyn, another monumental project on a former industrial site is also finally moving ahead. The Domino Sugar Refinery in Williamsburg sits on nearly a dozen prime acres facing the East River. It’s long been a sentimental favorite—the 40-foot-high Domino Sugar sign, with its jaunty script, sits like a comic-book dialog balloon over a grim Ashcan School tableau. The sugar factory closed in 2004; shortly afterward, it was acquired by the for-profit arm of a nonprofit seeking to build affordable housing. In 2007, the city landmarked the 1880s-era Romanesque Revival sugar refinery at the heart of the complex, and plans for its redevelopment called for residential towers to flank the old factory, much of which would itself be converted to apartments. Missing from the initial designs? The Domino sign. “It just looks empty, like there is a void,” Dewey Thompson, a member of Brooklyn’s Community Board 1, told a New York newspaper after seeing the designs at a meeting. Back to the drafting table: under revamped plans, a refurbished sign will glow again from atop the remodeled refinery.

The London and New York projects have several things in common. Chief among them: Rafael Viñoly, the Uruguayan-born, Argentinean-raised, New York–based architect famed for soaring steel structures such as the Tokyo International Forum and Seoul’s Samsung Jong-ro Tower. In charge of the master plan in both cases, he is designing new edifices for each site. But something else is worth noting: in both projects, Viñoly and his co-developers are trying to map a route through the hazy and treacherous borderlands that lie between architectural history and public nostalgia.

Viñoly’s studio is located on Vandam Street, in Manhattan, which by pleasing coincidence is the same street where William and Frederick Havemeyer established, circa 1807, the sugar factory that would eventually become Domino. When I spoke with him about the two projects, he radiated a wry detachment, sometimes sounding less like an architect than like an anthropologist trying to plumb complex and obscure rituals—in this case, how large-scale development navigates civic-preservation agendas on both sides of the Atlantic. And I thought I detected some irked undertones, as if he felt that he was working with a committee to design a setting for a jewel, rather than the jewel itself.

Viñoly made clear that he doesn’t think too highly of either gem he’s been handed. He panned the 1880s Domino factory as a pattern-book building, whose design was imported from Germany and is not native to the American industrial tradition. (What’s more, conditions in the factory may not have been worth celebrating. An 1894 story in the New York Tribune noted that the sugar-factory workers “are nearly all thin and stooped and rarely above middle age, it being a well-known fact that men employed in the refineries rarely live to old age.”) Viñoly designed the project to accommodate the factory; had it been torn down, he said, he likely would have arranged the buildings differently, playing off the nearby Williamsburg Bridge.

Although he acknowledged the heroic monumentality of Battersea, he’s slightly mystified by the public affection for the plant—people seem to forget that it is, after all, “a culprit in the history of pollution of the Thames,” and something that has helped destroy the climate. “It’s like preserving Dracula, somehow,” he said.

Cities are living projects, and must be constantly edited, often by an invisible hand—one structure needs to be deleted to make room for another, an early draft of this neighborhood is recast in a newer, tighter form. If nostalgia rules the day, nothing changes, nothing moves forward.

Still, it seems Viñoly may be more ambivalent than he need be about the historic structures on these sites—good arguments can be, and have been, marshaled that these buildings should be preserved for historic rather than sentimental reasons. But he’s right that, in general, nostalgia is gaining too much influence in these debates. “Train stations were done in the 19th century with some glamour,” he said. Now the preservation movement considers factories to be “as important as the Penn Station building, which they are not. But the narrative is the same.” Whether in New York or London, Viñoly lamented, the civic debate about setting preservation standards offers mostly shifting sands on which to try to construct something, before popular sentiment shifts yet again.

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