Marc L'Italien's idea for getting more from the Golden Gate Bridge: energy and clean water. Courtesy EHDD and Architecture and the City

In terms of architecture, San Francisco is a very tasteful city, which is to say it can be a tad monotone. Its hills, bridges and vistas exhilarate, amply making up for the dearth of built thrills.

That’s too bad. In other ways, the City by the Bay is magical and pioneering. It’s a hotbed of innovation in technology and public policy, two areas Mayor Ed Lee is now trying to bridge with hisentrepreneurship-in-residence program for “startups solving public sector problems.” This should set the stage for valuable experiments in architecture, right?

Yes, theoretically. And urban theory is exclusively where we see the city’s most forward-thinking design work.

On a recent visit, I witnessed San Francisco’s latent design innovation on display — for an alternative universe — in numerous venues in town and across the handsome, $6 billion new Bay Bridge, in Berkeley. One day, these audacious notions may lead to actual buildings and urban spaces. In the meantime, the grandiose ideas are mostly shelved but at least they are on view at two exhibitions of forthcoming and imaginary works.

If you unbuild it …

One of those exhibits is Unbuilt San Francisco: Ambition and Imagination, on view through December, which includes stunningly brilliant ideas that “never came to pass” as well as current schemes set for construction that couldradically alter the cityscape, should they go forward. The assembled photographs, original drawings, renderings and models are not only thought-provoking, they offer new solutions for serious challenges, too.

Fougeron Architecture, for example, illustrates how “vertical agriculture systems” could be woven directly into the city’s streets, bridges and buildings to make the region super-sustainable. It’s a veritable dream come true for the ultimate foodie town.

Water issues

Other designs consider the city’s rising sea levels and shrinking watersheds, such as Kuth Ranieri Architects‘ Folding Water, a ventilated levee beneath the Golden Gate Bridge that could protect shorelines and contain tubes for high-speed regional trains. Marc L’Italien of EHDD proposes a retrofit of the Golden Gate with an industrial desalination plant and hydroelectric generators powered by the Pacific Ocean’s vast tidal forces.

The Folding Water concept will protect against flooding and host high-speed trains. Courtesy Kuth Ranieri Architects

There’s more on tap, so to speak, in San Francisco’s unbuilt realm.

One dream held by locals is to demolish the earthquake-damaged freeways that run through and over many neighborhoods.Mayor Lee’s recent idea to demo the Highway 280 stub and minimize a CalTrain railyard includes a vision of turning Mission Bay into a scientific and commercial hub. It’s not a new idea — the ugly double-decker Embarcadero Freeway was dismantled following the 1989 Loma Prieta quake, and the Hayes Valley also benefited from highway elimination.

Responding to the spirit of the Mayor’s plan, the Center for Architecture + Design (CAD) along with the angels at the Seed Fund launched a competition called Reimagine. Reconnect. Restore: What if 280 came down? The results are astounding and on display at CAD and online.

More bikes and walkers

Compelled by a desire to further pedestrianize and bicyclize the dense city and push more bodies into mass transit, designers came up with schemes such as Brian Vargo’s Highlink, which uses the existing 280 overpass as a promenade, reconnecting Mission Bay to the city. Another idea along the lines of Anne Fougeron’s farm-city is Seismic Harvest, a scheme by D.I.S.H. using community gardens, commercial organic farms and waterfront development with integral earthquake simulators that serve as “harvesting systems.”

The Highlink idea from Brian Vargo, to be built when Mayor Lee closes Highway 280.

Among the jurors forReimagine was the omnipresent Allison Arieff, former Dwell editor and New York TimesOpinionator columnist. She and others — likeJohn King, San Francisco Chronicle’s urban design critic — are behind these competitions and many of San Francisco’s best emerging ideas. They’ve also helped propel the city’s real achievements globally, especially as a tastemaker and innovator that often gets the idea done before New York and others.

Un-unbuildings

Yet their city needs more investment in design, as these idea expos prove. The mayor probably won’t be the catalyst. The leaders of the tech industry might be, if they can get their act together.

A tower that's also a community farm, by Fougeron Architecture

The time is ripe. The exhibitions continue on the heels of what organizers touted as the world’s largest architecture festival, the month-long Architecture and the City Festival, which wrapped up on Sept. 30. Hosted by the American Institute of Architects (AIA), San Francisco Chapter, the entire program of tours, films, exhibitions, parties and talks has elevated the dialogue. (It has also likely helped inspire other city design festivals such as New York’s Archtober, which I help promote.)

Yet the theme this year — “Unbuilt San Francisco” — surely gives the wrong impression to the public.

While it’s laudable to elevate great ideas and showcase the potential of what might be, we also need to criticize their failures and patrons. It’s time for San Francisco to concentrate efforts and resources to build these great places and technical feats, too. For this world-leading city, it’s only a matter of desire.

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