Dam dead people

This, courtesy of my friends at JournoBiz, that the first and last people to die in construction of the Hoover Dam were J.G. Tierney and P.W. Tierney-father and son and they both died on December 20 (13 years apart). Tierney Senior who died in 1922 drowned in the Colorado River while undertaking a geological survey in the preparations of the dam and his son fell from one of the intake towers.
Here's a cheery list of the industrial fatalites - though there were plenty more deaths caused by heat and exhaustion.