Disintegration Patterns

A scattered drifting disassembly of mountains. Disintegrated edges as you roll.

Loosening up as a way of friendship.

The South end of Ocean Beach in San Francisco is an odd anthropocenic geological site. The layers go: Pacific Ocean, a narrow stripe of sandy beach, contained by a humanmade landslide of concrete, ballast, sand bags the size of king sized mattresses, construction materials, and then two versions of the Great Highway - one that’s a discontinued ghost, crumbling off the edge of the continent and one that is still being used just slightly east. I ask Patrick Barnard of the USGS, from the geological perspective, how do we read all those different layers of human and non-human geology all jumbled together?

He answers that this construction debris landslide was a quick response to a particularly harsh El Niño in 1997-98. The crumbling human-made landslide a way to fortify the Great Highway in the case of much stronger than usual winter waves.

The winter beach and the summer beach are hardly the same place. Beaches breathe. They expand and contract dramatically over the seasons. Patrick says that our seasonal wave climate means small waves in the summer that then double in size on average each winter. Large winter waves and storms take sand away from the beach and store it on bars, then returning this sand to the beach each summer. Patrick and USGS teams have done monthly surveys on Ocean Beach since 2004 and have found it to erode temporarily, about 65 ft, each winter.

In all this, the Great Highway is a constrictive belt that doesn’t allow for low-stakes natural erosion and movement of the beach. Patrick says that at this point: “The ocean wants to be further landward and naturally it used to be further landward. Around the turn of the 20th century the Great Highway was extended considerably along that entire stretch, I believe to basically create more land and a highway and so, naturally the shoreline does not want to be there. So, if the beach has nowhere to go, it can’t erode any further landward, it runs into a wall, so when you have a kind of ridgid structure it tends to amplify the scouring potential of the waves and the beach tends to erode more rapidly. Whereas, if you have big wide beach that has lots of room to move back and forth it tends to disipate the wave energy.”

Patrick shares also that: “Outside of water, sand is the second most valuable natural resource in the world. There’s a huge demand for sand. I mean the whole city is made out of sand when you think about it: the buildings and all the concrete foundations, and then there’s the natural sand, and the sand that’s been used to build up the whole area.”

“The whole Bay Area is really analaogous to every development story in the whole world. We try to tame nature. In the case of San Francisco, its both for flood control and these unruly sand dunes. So we had this incredible resource of sand and water and we tame it and now we’re realizing we need these resources again. We need sand and we need water.”

The need for sand and an extractionist relationship toward it is part of a global crisis in sand shortage and the ensuing environmental injustices, civil wars, and violent sand mafias that span the globe.