A secret seismologist landmark in Hayward, California was accidentally destroyed recently by some guys just trying to do their jobs. As reported in the Los Angeles Times, a small bit of sidewalk at the corner of Rose and Prospect Streets, had acted as an unofficial barometer of local geologic activity since the 1970s.
The corner curb just happened to have been built almost exactly on the Hayward fault line, just one of the many potentially catastrophic faults underlying California’s geography. As can be seen in vintage photos dating back as far as 1971, the corner section of the sidewalk has slowly been growing out of alignment with the rest of the cement path, the fault perfectly dragging the two sections apart so that the corner curb juts out like a book coming out of a shelf.
The accidental seismic indicator became a sort pilgrimage site for earthquake specialists who documented the perfectly described movement of the fault-via-sidewalk for decades. Unfortunately, not everyone has a seismologist’s eye for the sidewalk.
Just last month, seismologists arriving to take a look at their secret landmark found it had disappeared, replaced by a wheelchair accessible sidewalk ramp, and, disappointingly, a nice, straight curb. The city, seeing the out-of-whack bit of curb as nothing more than a bad bit of masonry, took the opportunity to upgrade the corner sidewalk, but in doing so erased the Hayward-indicating curb from existence. Just doing their job.
When they discovered the significance of the curb, the city said they would have been more careful had they known. Even though the earthquake curb is gone, seismologists speculate that the Hayward fault is primed for another catastrophic earthquake at any time, so a curbside reminder of its existence may soon be a null point.
This article has been updated. A previous version incorrectly said the corner was in Los Angeles.
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