In this edition of Soonish, we dive into the ancient tension in urban planning between the old and the new. Should we do everything we can to preserve the parts of the environment that connect us to our past? Or should we boldly remake that environment to support growth and innovation in the future? Is there a way to do both at once?

The episode approaches those questions through the story of two bridges. One is the Longfellow Bridge, the 110-year-old, European-style steel arch bridge that carries cars and Red Line subway trains over the Charles River between Cambridge and Boston. The other is the Zakim Bridge, a modern concrete-and-steel cable-stay bridge that soars over the Charles just a mile downstream.

Both are iconic structures familiar to all Bostonians. But they’ve come to represent very different sets of ideas.

With its striking design, the Zakim Bridge still looks like it arrived from the future via time warp, even 15 years after its completion. It presents drivers with a grand entrance to Boston as they swoop down toward the city on Interstate 93 and dip underground into the Central Artery tunnel.

“I think the Zakim Bridge gave Boston a new image, like a cool city, a high-tech city with all these things to it,” says Miguel Rosales. He’s the Boston-based bridge architect who proposed a cable-stay bridge as a fitting punctuation mark for the north end of Boston’s massive Big Dig, and then helped to design it.

Meanwhile, the Longfellow Bridge represents Boston’s rich architectural and literary history. It was the first grand European-style bridge in North American, and after it opened it was renamed in honor Henry Wadsworth Longfellow, perhaps the 19th century’s most famous American poet.

But it also represents bother, delay, bureaucracy and the crushing costs of deferred maintenance.

After a century of decay, the Longfellow is in the midst of an expensive rehabilitation project. That effort is about two years behind schedule, thanks in large part to historical preservation regulations that forced contractors to revive obsolete construction techniques like hot riveting. The bridge is expected to reopen sometime in 2018. And in the end the price tag for fixing the Longfellow will be more than twice that for building the Zakim.

Which brings up an obvious question: Wouldn’t it have been cheaper and more effective to tear down the Longfellow Bridge and start over?

Tom Keane, a writer and former Boston city councilor, voices that point in the podcast. “We could have built a great, cool bridge across the Charles here to replace the Longfellow Bridge and it would become the symbol of Boston for the future, rather than Boston for the past,” Keane argues.

But that option was never seriously discussed — partly because the Longfellow Bridge is on the National Register of Historic Places, and partly because its “Salt and Pepper” towers are such a familiar part of the city’s skyline.

“It would have been very hard to demolish it, because it is loved by so many people,” says Rosales, who was also the architect of record for the Longfellow restoration project. “That would have been a big, big controversy.”

So, the state government that’s restoring the old, undersized Longfellow Bridge at fantastic expense is the same state government that conjured the futuristic Zakim Bridge into existence. Clearly, the impulse to preserve and the impulse to innovate can coexist, though sometimes uneasily. In the show, we delve into those conflicting impulses, and we also go to San Francisco to hear how one arts organization is using technology to get people to think differently about its own main thoroughfare, Market Street.

*[This podcast was originally featured by Soonish.]

The views expressed in this article are the author’s own and do not necessarily reflect Fair Observer’s editorial policy.

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