There’s a well-known book by a local writer titled What is the What. As catchy as the title is, it also makes sense. What IS the “what”? In a conversation with a colleague, I ended up saying “the HOW is the how”. The way we do things is the way things get done.
Apply that methodical step-by-step approach to rebuilding a major thoroughfare into the city from the Golden Gate Bridge. On May 2, a new highway segment opened. It’s not the fully completed replacement because everything has to be broken down into steps, excepting nothing if you want it done right. And in this case, it has to be engineered right, with no room for mistakes.
I’ve always found highways and transportation to be a fascinating mathematical subject. At what speed can this curve be built for cars going 35 mph? What about 55 mph? What is the percent grade of a mountain and how are the vehicles affected by the size of the mountain, the payload, I think it’s called, the speed of cars vs trucks, the incline and descent. How does the design optimize topography to take advantage of valleys between hills, conserving both the amount of land being destroyed and the auto’s energy use?
In this specific project of the Golden Gate Bridge connector, how does a major transportation vein into the city get parsed into separate stages because there’s not enough land to build a complete new highway, then close the old one? What space does CALTrans (the state transportation agency) have available to create two side-by-side multi-lane roads without encroaching Presidio Trust lands bordered by historic buildings and a roadside cemetery.
New roads must be engineered to fit like puzzle pieces into old roads, so that the old roads can be removed. Then the next phase involves reclaiming and rebuilding on the old road that magically (engineering magic, anyway) fits back into the new road, which becomes the old road.
As I drove by the weekend’s demolition of the old Doyle Drive and introduction of a new tunnel, I marveled at a project that takes years…YEARS…to manifest only a portion. I stared at the remains of a tear down that took 3 days to stack cement columns like dominoes, one resting upon the other. The scene was vaguely reminiscent of the ’89 earthquake, though nature used only 15 seconds to pancake. I admired the math behind the beautifully smooth and curvy road that wove back into old road seamlessly. On my first day, and I’ve only driven on this road twice since it opened last week, I was glad of the traffic so that I could admire the tunnel, the lights…the engineering. As the roads start to grey with rain wash-off, graffiti, rubber tread marks and other hazards of the road, it will never be the same again.
But I guess that’s the point, isn’t it?