The Atristry of San Francisco's Bay Bridge

The San Francisco-Oakland Bay Bridge is composed of several parts, beginning with a sleek skyway from the Oakland side that leads to the new, self-anchored suspension bridge--with its looming, single white tower. The span then leads onto Yerba Buena Island in the middle of the bay.

On the other side of the island, the old double-decker west span, which has been retrofitted to higher earthquake standards, completes the crossing to San Francisco.

But it was the artistic component of this western part that we wanted to see after our day in Chinatown.

The background on this project was summarized by Doug Stanglin (USA TODAY, September 3, 2013):

"San Francisco's lesser-known bridge unveiled a new look. As part of a unique art project celebrating its 75th anniversary, the West span of the Bay Bridge has been outfitted with 25,000 LED lights (attached to the cables shown below) that will display a variety of undulating designs nightly for the next two years.

"Organizers say it is the world's largest light sculpture."

So, to view the light show, cousin Barbara found a parking spot on the Embarcadero. I found a viewing point on one of the piers a few blocks north of the Ferry Building and prepared to photograph the show. An Alcatraz Cruises boat (left) and the San Francisco Belle are shown in the foreground in the photo below.

"'Light has a very universal quality, almost anyone can see it and have some response to it. It's operating on a very primal level,' said artist Leo Villareal, who has been working on the project for the past two and a half years. He says his goal with the Bay Bridge installation was to create a 'digital campfire.'

"The utilitarian grey bridge cuts a striking figure in the bay and transports 250,000 cars a day, but it has never been a tourist attraction like the nearby Golden Gate bridge. The Bay Bridge, which opened just six months before the Golden Gate in November 1936, can't compete with its neighbor's iconic touches: epic views, vivid orange paint job and art deco detailing.

"The Bay Bridge lights will fire up nightly at dusk and turn off at 2 a.m. every night until 2015. The energy-efficient lights cost $30 a night to power for those seven hours.

"The final project contains 25,000 LED lights strung up along the 1.8-mile stretch of bridge connecting San Francisco and Treasure Island. The individual lights are spaced 12 inches apart and each one can be set to one of 255 brightness levels. The designs Villareal created and programmed to flicker across the bridge don't include any images or text, and the sequence won't ever repeat itself.

The Ferry Building tower is shown in the background

"'What people will be seeing are abstract sequences which are inspired by the kinetic activity around the bridge,' said Villareal. 'It's not literally traffic or the water or any of those sorts of things.'

"The result is an open-ended piece of art that Villareal calls highly subjective. Lights might dim slowly from the edges or shapes will unexpectedly dart across the surface like comets. The movements are playful, relaxing and unpredictable.

"While designing the sequences, Villareal had to address practical issues like safety for passing boats and drivers on the bridge, as well as artistic considerations such as making sure the animations were viewable from up close, below the bridge, and as far away as Twin Peaks, where the bridge can been seen on fog-free nights.

"After obtaining permits and securing funding, trimming the bridge was the final daunting step of the project. Teams worked from 11 p.m. to 5 a.m. over the past few months to install the fiber optic network, choosing late night hours in order to have minimal impact on bridge traffic. They used custom clips to hang the lights on 300 vertical spans, mounting some lights as high as 500 feet.

"Mayor Lee predicted an extended lifespan for the project, saying the city will want to keep the display longer than its two-year engagement. He hopes it will help give San Francisco the reputation as a location for world class art.

"Relieved to finally hit the 'On' button for the project after years of work, Villareal isn't thinking that far into the future at the moment. 'We'll cross that bridge when we get to it,' he said."

I had just started packing up the tripod, when something happened that shouted "Wait a minute."