2011 Mississippi River floods
severe flooding across the Mississippi River Valley affected Louisiana

Major floods along the Mississippi River in April and May 2011 were among the largest and most damaging recorded along the U.S. waterway in the past century, comparable in extent to the Great Mississippi Flood of 1927 and Great Flood of 1993. In April 2011, two large storm systems deposited record levels of rainfall on the Mississippi River drainage basin. When that additional water combined with the springtime snowmelt, the river and many of its tributaries began to swell to record levels by the beginning of May. Flooding occurred in Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana.
U.S. President Barack Obama declared the western counties of Kentucky, Tennessee, and Mississippi federal disaster areas. For the first time in 37 years, the Morganza Spillway was opened on May 14, deliberately flooding 4,600 square miles (12,000 km2) of rural Louisiana to save most of Baton Rouge and New Orleans.
Fourteen people were killed in Arkansas, with 348 killed across seven states in the preceding storms. Thousands of homes were ordered evacuated, including over 1,300 in Memphis, and more than 24,500 in Louisiana and Mississippi, though some people disregarded mandatory evacuation orders. The flood crested in Memphis on May 10 and artificially crested in southern Louisiana on May 15, a week earlier than it would have if spillways had not been opened. The United States Army Corps of Engineers stated that an area in Louisiana between Simmesport and Baton Rouge was expected to be inundated with 20–30 feet (6.1–9.1 m) of water.
Begin with the source’s own compact description: “2011 Mississippi River floods” is severe flooding across the Mississippi River Valley affected Louisiana. The dossier treats that line as a proposition to test through Mississippi, River and floods, not as a finished interpretation.
Why this record matters
The phrase “severe flooding across the Mississippi River Valley affected Louisiana” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Aug 22, 2026. The linked authority identifier is Q1135487. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2011, 1927 and 1993.
Architectural summaries often privilege surviving fabric and can understate demolished phases, contested use or displaced communities. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “2011 Mississippi River floods”, its source revision and the description used here.
- Expand the search: follow 2011 Mississippi River floods primary sources, 2011 Mississippi River floods archive and Mississippi research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “2011 Mississippi River floods”?
- Which earlier names or jurisdictions may reveal additional records?
- Which authority defined the place, boundary or structure at the relevant date?
Search terms from this dossier
This entry incorporates text from “2011 Mississippi River floods” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.