Sometimes Construction Methods Don't Change

Image courtesy of https://auto.howstuffworks.com/horsepower.htm

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The photo below was taken in 1918-- when the first Calaveras Dam was being constructed.  These workers are excavating in the dam's foundation.  They're using using 4-mule carriages(4-horsepower) to do the job. Each power train (4-mule carriages) transport approximately 4 cubic yards per load at a speed of 1 to 2 mph. 

Fast forward a hundred years.  The photo below was taken at the new Calaveras Dam as workers were excavating the new core.  The workers in this photo are doing the same job with a Caterpillar Motor Scraper with a 450 horse power engine capable of carrying 30 cubic yards at a speed of 25 to 30 mph.

Although times have changed, sometimes the methods don't.  

See you around the valley!