The Geology That Keeps Winning

In May of twenty seventeen, roughly forty acres of the Santa Lucia mountains slid into the Pacific Ocean. The Mud Creek slide deposited enough material to add approximately forty feet of new coastline to California, closing Highway One for more than fourteen months. It was not a disaster by Big Sur standards. It was the geology behaving as expected.

Big Sur sits at the boundary between the Pacific and North American tectonic plates. The Santa Lucia mountains are among the fastest-rising coastal ranges in North America, pushed up by the same forces that make the San Andreas Fault a permanent feature of California's geography. The faster a mountain range rises, the faster erosion and gravity work on it. The cliffs are not stable. They have never been stable. The engineers who designed Highway One in the nineteen twenties and thirties knew this and built the road anyway, because the alternative was no road.

The highway has been closed by slides in nineteen eighty-three, when the Pitkins Curve slide took more than a year to repair, and again in twenty seventeen, and has been periodically threatened by fires and floods in the years between. Each closure isolates the several hundred year-round residents of Big Sur, who have historically stocked months of supplies and relied on helicopter drops when the road is gone.

There is a word for what the road is attempting here. The word is temporary. The Santa Lucias will eventually provide more coastal acreage, and the engineers' descendants will decide where to put the road.