The Flood Control Act of 1934 was an accidental creation based on a typographical error [1]. The reference should be to the Flood Control Act of 1936, Pub.L. 74–738 [2]. The 1934 date referenced in the 2003 textbook was a typographical error that went uncorrected through several editions. Countless references to it were made (including on the FEMA training pages). It was first identified during fact-checking of another manuscript in 2013, and corrected in time for the 2014 publication.
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Flood Control Act of 1934 Wikipedia(Text) CC BY-SA