Al Roker talks about ‘Ruthless Tide,’ his new book about the Johnstown Flood

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The 1889 Johnstown Flood, which claimed the lives of more than 2,000 people, is the subject of a new book by TODAY’s Al Roker, “Ruthless Tide.” Roker explains how the catastrophe was caused by the actions of a few “one percenters” of the time, calling it “a watershed moment of American history.”