Power Trip

composite showing transmission towers in different settings, like grass hills, steep mountains, and rocky cliffs

This project began when I learned that San Francisco receives all of its municipal power from a dam at the Hetch Hetchy Reservoir in Yosemite National Park. "Municipal" means things like city streetlights, SF General Hospital, the SFO airport, SFUSD public schools, fire stations, and the MUNI transportation system. When I looked for a map online, the only one I could find was abstract: it included just two tower symbols and a couple of straight lines. Wanting to see the route for myself, I used Google Satellite to painstakingly trace the transmission and towers and lines from the Newark substation in the East Bay, where the power enters the grid, to the Kirkwood Powerhouse in the Sierra Nevada Mountains, where the flow of Hetch Hetchy water is first converted to electricity. I then used this map to generate driving directions for a trip in the summer of 2013.

screenshot of Googe Earth with markers along the Hetch Hetchy system route

It was an difficult route, since the transmission lines disregard all boundaries, crossing public and private lands and sneaking through backyards and inaccessible ravines. Ultimately, the route would take me past the suburbs of Fremont, a paintball park, a series of vineyards, a road named for Tesla, a vehicular recreation area, the San Joaquin River Nation Wildlife Refuge, orchards and farms, a veterinary hospital parking lot, traffic jams and shopping centers in Modesto, a Del Taco, a fruit stand, an endless expanse of yellow grass (a wintering home for bald eagles, and thus an Area of Critical Environmental Concern), a crystal-blue reservoir, and Moccasin, a town mostly owned by San Francisco for the purpose of maintaining the Hetch Hetchy line.

sign that says: Moccasin Powerhouse, Hetch Hetchy Water & Power, San Francisco, with power lines crossing forested mountains in the background

Past Moccasin, my Google directions completely failed me – telling me to turn right onto Forest Route 1 from Forest Route 1, for example – as my route twisted onto steep, mostly deserted roads. After several unsuccessful attempts, I found the Kirkwood Powerhouse at the bottom of a canyon. Hetch Hetchy water, which flows underground from the dam to this point, emerged as a white pipe that dropped straight down the severe face of a mountain. Then, across the river, the generated electricity clambered up the other side of the canyon via the transmission towers, which had never looked so precarious.

a nearly vertical white pipeline going down the side of a severe mountain face a utility building, transmission lines, and a substation at the bottom of a steep canyon, viewed from above

It was this characteristic of the system -- so vulnerable, so unlikely, with its spindly structures making complicated maneuvers through dense suburbs and famously large mountains just so that a bus in San Francisco could open and close its doors -- that struck me the most. To a person completely unacquainted with contemporary civilization, it would seem obvious that the towers and pipes (the Kirkwood penstock's vertical drop being totally baffling to the eye, describable only as sublime) are monuments. Instead, my curiosity about a public good -- and my camera -- simply aroused suspicion.

large transmission towers in the background of a suburban basketball court

The fact is that photographing these structures was by no means illegal, but it was also not expected, because (especially where it exists above ground) the power grid is one of the best examples of something that is all around us but which we have learned not to see. As a child I would often take pictures in my neighborhood and be dismayed when there turned out to be power lines in the photo– as though they had materialized in the picture itself. The towers of the Hetch Hetchy line stand unassumingly in fields next to the freeway and in the back parking lots of shopping centers, invisible unless you're looking for them. But now that I have sought them out, I can't forget their image. When the J MUNI line comes to pick me up in the morning, seemingly banal as ever, I know that it's driven by water rushing straight down a monumental pipe in a remote canyon in the Sierra Nevada.

The video below, containing images from all along the route, was exhibited in INFRASTRUCTURE at Intersection for the Arts. The soundtrack is an original home recording by my father, an electronics engineer.

A wall-mounted screen showing a video of the transmission towers, with maps and information on one side, and a short essay on the other
(photo: Scott Chernis)
abstract utility map of the Hetch Hetchy system, showing only major points along the route A hand-drawn map showing a handful of sites along the Hetch Hetchy system route