It’s just after nine o’clock on a chilly winter morning. Much of Coronado has been up for hours, and the toll plaza at the foot of the bridge that ties the tranquil island community to San Diego has quieted down substantially from the frantic rush a few hours before. Toll collectors, able to relax a bit as they sit in their tiny steel booths, munch on midmorning snacks and trade barbs with each other across the traffic lanes. Over on the nearby golf course, tow old men interrupt their game to look east at the San Diego skyline silhouetted against a gray backdrop, the chocolate tops of the Laguna Mountains providing the panorama’s only touch of color. And H.B. (Byrd to his friends) Thysell is getting ready to walk across San Diego Bay on a four-foot-wide wire-mesh catwalk underneath the San Diego Coronado Bridge.
As Bridge manager, it’s Thysell’s job is to maintain and operate the massive structure; his duties include supervising toll collections and various maintenance functions, as well as planning for the bridge’s future needs. Once a moth he strolls along the narrow catwalk to inspect the bridge’s vital parts, looking for any structural damage that might have occurred since his was walk determining what sections, if any require maintenance. A slight man of sixty-two with tightly cropped hair, Thysell clearly loves his job, and speaks of “his” bridge with paternal affection as he walks toward his car in the administration building parking lot just west of the toll plaza. ‘It really is a beautiful bridge, a monumental bridge,” he says.
The half-mile road from the parking lot to the bridge’s physical base winds its way along the shore north and east of the toll plaza and ends up directly beneath the bridge. Thysell drives his car along the narrow, twisting road with the absent-minded ease that comes from having traveled the same route many times before. He’s been manager of the bridge for than ten years, and might justifiably view the monthly inspection tours as routine; but he doesn’t. ‘I suppose I’m a bridge buff to start with, and I like to keep abreast of what changes re going on,” he says, ‘the painting maintenance program, in which various parts of the bridge are repainted sooner than others, is a direct result of one of my walks.” After parking beside one of the bridge’s land-based stanchions, or “piers,” Thysell strides up the three flights of stairs that lead to the start of the catwalk. He unlocks a steel door at the top of the stairs, opens it and begins his two mile walk across the bay.
From the air, the San Diego Coronado bay bridge looks like a gigantic letter J. It measures 11,179 feet, just under two and a quarter miles, from Crosby Street and Logan Avenue in Sa Diego to its Coronado base at Fourth Street and Glorietta Boulevard. In the language of engineers, it’s known as an orthotropic bridge, one in which the main sections are constructed in the manner of rectangular boxes serving as the roadway. (Most conventional bridges have their roadway attached separately to the horizontal supporting structure.) Three of these boxes span the center portion of the bridge, and their combined length of 1880 feet is unmatched by any other orthotropic bridge in the world. The roadbed, a mere nine inches thick, is 243 feet above the bay at its highest point. From curb to curb it stretches across five lanes measuring twelve feet each. The concrete bridge rails are only about three feet high (so motorists can take in the view) and are constructed so that the wheels of a colliding car strike it first and the vehicle is thus hurled back onto the roadway. All of this is supported by thirty concrete towers which, in turn, are supported by concrete pilings hammered up to 160 feet into the bay.
The bridge’s sleek design is primarily the work of two architects, Steve Allen of San Francisco and Robert Mosher of La Jolla, who acted as design consultants during the bridge’s construction. (After the state built the San Rafael-Richmond Bridge in 1956, an open-trestle span Mosher describes as “so bloody ugly and awkward . . .a horrible bridge,” the state division of bay toll crossings was directed by Governor Pat Brown to hire a design consultant for all future toll-bridge constructions. “A committee of people came to San Diego and interviewed four local architects for the job, including me,” Mosher recalls. “When they came into my office, I told them from the start that I’d dedicated myself to preventing construction of the bridge. At the time my feelings were that if there was no easy access to Coronado, the rural community there would not be ruined, as was Staten Island with the construction of its bridge in the Fifties, and San Diegans would always have a charming contrast in environment experience. So these guys [the committee members] asked me why I had let them talk to me, and I told them that I was a realist, knew that Pat brown was paying off a political debt to Coronado landowners, and would get the bridge built; and that being the ease, I wanted to help design the most beautiful bridge possible. I was hired. So for the next year, Steve and I just reviewed and contributed to the ultimate design of the bridge. Steve wanted to paint his new penny copper, which he had used on the San Mateo-Hayward Bridge, but I knew how Coronado was against the whole project and felt it would go over much better if we painted it blue to span the bay and the sky, and the directors agreed with me.
“The design itself was relatively simple to arrive at. The cities of Coronado and San Diego wanted it to be arches (curved) so it would flow into the desired access streets; the state division of highways also wanted an arch to maintain highway speeds of sixty miles per hour; and the Navy wanted a certain amount of airplane clearance over the bay. So when they all got through telling us their requirements, we just took a pencil and drew what was built.”