There have been considerably more dam failures though: https://en.wikipedia.org/wiki/Category:Dam_failures_in_the_United_States https://en.wikipedia.org/wiki/Ca

There have been considerably more dam failures though: https://en.wikipedia.org/wiki/Category:Dam_failures_in_the_United_States https://en.wikipedia.org/wiki/Category:Dam_failures_in_the_U... Which is the point: any retained body of water like this is a significant geotechnical engineering project.