JOE MATHEWS: A tale of two cities’ new bridges

Comparisons are instructive because the civic gifts in question are so similar. L.A.’s new Sixth Street Viaduct and San Francisco’s new Presidio Tunnel Tops are both expensive new bridges that double as public spectacles.

In July, L.A.’s new $588 million bridge opened hot — too hot. The city was unprepared for the hordes that would descend on this beauty of a bridge, with its unmatched skyline views and its “Ribbon of Light” design.

We Angelenos did what we do with new infrastructure: test its limits. Moped racers did wheelies. Truck drivers and bicyclists swarmed, taking over the bridge for brief periods. Taggers added graffiti and climbers went up the bridge’s steep arches. The official response was the typical L.A. overreaction based on fear. The authorities, citing “illegal activity” and “unruly crowds,” closed the bridge repeatedly — four times in one five-day period. And the city announced structural changes — fences to deter climbers, speed bumps to slow down street racers.

Local and national media then did their tired tsk-tsking about the inability of Angelenos to behave with decorum.

C’mon. Our collective lack of decorum is why — as Randy Newman sang — we love it!

That didn’t stop holier-than-thou types in civic life from spewing cliched nonsense about the supposed crisis of Sixth Street. City Councilman Kevin de León suggested that Angelenos were overly excited because we lack accessible public spaces — which is self-pitying nonsense in a metropolis full of fantastic gathering spots. The L.A. Times editorialized that the bridge, built as a transportation connector between Boyle Heights and downtown, should be closed to vehicle traffic. What’s next — closing Dodger Stadium after eight innings because closing pitcher Craig Kimbrel keeps making a mess of the ninth?

A week after the L.A. bridge opening, and 400 miles north, the $118 million Presidio Tunnel Tops opened to the public. It’s essentially a privately financed park that’s also a pedestrian bridge over Presidio Parkway, a road to the nearby Golden Gate Bridge. More than two decades in the making, Tunnel Tops connects the Main Post section of the Presidio, the military base-turned-national recreation area, to Crissy Field and the beach below.

Tunnel Tops is cool, and not just because of San Francisco’s winds and mild temperatures. It’s got magnificent views of the famous bridge and the skyline; green meadows for picnicking and napping and kite-flying; gardens of native plants; public art; a pretty Field Station building for kids’ science lessons; and an innovative children’s playground called the Outpost.

John King, the San Francisco Chronicle’s brilliant urban design critic, knocked it for lacking a “sense of arrival,” and for broad walking paths and concrete slopes that suggest “crowd control and maintenance needs won out over design intent.” But given what happened in L.A., designing for crowd control seems prescient.

The park is an instant success. On its opening weekend, San Franciscans enthusiastically entered Tunnel Tops even before it was officially open, and crowds were immense. But there were no reports of dangerous incidents, and there was no security crackdown. San Francisco played its new bridge as cool as Los Angeles played its new span hot.

This summer, your columnist visited each of these new public spaces. Police closures foiled my first three attempts to cross the Sixth Street Bridge. But when I finally made it out there, I felt comfortable and safe. A few passing motorbikes did tricks, but police didn’t stop them. They also didn’t stop pedestrians (your columnist included) when we raced across the traffic and bike lanes to check out different views. My only complaint was the lack of places to sit down. But that should be addressed, in part, as soon as next year, when Los Angeles is scheduled to build a new park under the viaduct.

My visits to Presidio Tunnel Tops were quieter than Sixth Street despite the presence of even more people. The first time, I spent an hour just lounging around on the grass, and in chairs that are set up around the park, enjoying the bridge and city views.

Then I got up to explore the new facility. At one point, in my wandering, I stepped over a low rope to check out some of the plantings in one garden. Within seconds, two people — not security guards, just local folks out enjoying the park — called out, “Sir, please don’t walk around the plants. We’re not supposed to do that.”

I quickly retreated, and then apologized — explaining that I’m from Los Angeles, and don’t know any better.