In 1927, Louisiana dynamited a Mississippi River levee to save New Orleans, flooding the homes of about 10,000 people downstream, and the city turned out never to need it

The Great Mississippi River Flood of 1927 is one of the most profound events in U.S. history. The deluge would effect 170 counties and parishes. It would put all private flood insurance companies out of business by 1929 and eventually lead to the creation of the National Flood Insurance Program in 1968:

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