Large scale , localised flood control measures such as levees had been constructed since the early 1900s , especially in the decade after the Great Mississippi Flood of 1927 and following the Flood Control Act 1936 . From 1928 onwards , the Army Corps of Engineers built a huge number of locks , run-off channels and extended and raised existing levees . These control measures only targeted single sites , and did not look at the entire river system
Great Mississippi Flood of 1927
Great Mississippi Flood of 1927
Mississippi River Basin Model