Helicopter hovers over flooded area following passage of Hurricane Betsy. 164,000 homes were flooded in this storm. Small loss of life as residents heeded warnings. New Orleans, Louisiana. September, 1965. Hurricane Betsy was a Category 4 hurricane of the 1965 Atlantic hurricane season which caused enormous damage in the Bahamas, Florida, and Louisiana. Betsy made its most intense landfall near the mouth of the Mississippi River, causing significant flooding of the waters of Lake Pontchartrain into New Orleans.