If you got woken up on Saturday night by the 6.0 Earthquake in Napa, you might have thought something along the lines of “Drop, cover and hold.”
If you live in Winters, California though, your first thought was likely “The dam!”, quickly followed by “where is the nearest tall tree I can climb.”
The timing of the quake on Saturday was a bit of a coincidence for the Winters community. You see, we hold an Earthquake Festival every year to commemorate the anniversary of the magnitude 6.6 quake that leveled our town in 1892. The festival was last Friday night, even though the quake itself was in April.
Many things have changed in Winters since 1892. But arguably one of the biggest is the construction of the Monticello Dam, 10 miles upstream from our town on Putah Creek, in the 1950s. The dam, which created 50 mile long, 300 foot-plus deep Lake Berryessa, was built directly atop the Green Valley fault.
If a giant earthquake were to strike along that fault and cause the dam to break, folks in Winters would have just a few minutes to reach high ground. No one knows exactly how deep the water would only be when it hit our town, but it would be moving pretty fast and carrying alot of larger objects with it. Houses would get pushed off their foundations and cars would float down the streets. Of course, a quake big enough to crumble the dam would probably already have flattened the town, just like the last time. I’ve heard old-timers say that the flood would just be insult on top of injury.
Closer to the dam, however, the water would be much deeper. The ranch where we plant our strawberries each year, for example, is just 5 miles from the dam and right below the narrow canyon leading down from it. Water there would be much, much deeper and moving much faster. It would scour the entire landscape, uprooting trees, washing away buildings and probably drowning anyone in the area. And it would arrive just minutes after the dam broke.
On a daily basis, the Monticello Dam is a hugely positive influence on our community, providing us with recreation and the business it brings in as well as abundant irrigation water. But if and when that giant earthquake hits, well…we just try not to think about it.
As it was, the 6.0 quake on Sunday shook us out of bed and broke a few dishes, but nothing more. The Bureau of Reclamation did a full inspection of the dam on Sunday and concluded that it had survived the quake with zero damage. If another 6.6 quake like the one in 1892 hit, though…who knows.
Our hearts go out to the folks in Napa whose houses shifted off their foundations and the winemakers whose vintages were destroyed. But there’s no escaping what we were really thinking on Sunday morning: Better there than here.