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Posted on @rawstates
Crystal Springs Dam, the first mass concrete dam in the country, built beside the fault
1889
San Mateo County, California
The original uploader was Kglavin at English Wikipedia. · CC BY 2.5 · Wikimedia Commons
The Spring Valley Water Company finished this concrete gravity dam across San Mateo Creek in 1889, the first mass concrete dam built in the United States and briefly the largest concrete structure in the world. It stands about 1,100 feet east of the San Andreas Fault, which is roughly the worst address in California for a dam, and it came through the 1906 rupture without failing. San Francisco still drinks the water it holds.
That was 1 of the hidden places.
Location: documented spot
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