A digital dataset of the geomorphology of the Lower Mississippi River Valley in Missouri, Kentucky, Arkansas, Tennessee, Louisiana, and Mississippi was developed from Roger T. Saucier’s “Geomorphology and Quaternary Geologic History of the Lower Mississippi Valley, Volumes I and II” (1994) as part of the Mississippi Alluvial Plain (MAP) Regional Water Availability Study. The maps included in the 1994 reports provide a comprehensive overview of the previously misunderstood alluvial valley geology and characterize twenty-nine Pleistocene and Holocene alluvial deposits, such as point bars, abandoned channels, backswamps, and natural levees. Each map was georeferenced to North American Datum 1983 and projected to USA Contiguous Albers Equal Conic (U.S. Geological Survey version) projection (standard parallels 29.5 and 45.5 degrees, central meridian -96 degrees, and latitude of origin 23 degrees). Once georeferenced (using ArcMap v 10.4.1), individual geomorphological features were digitized manually. Each polygon was validated using a geodatabase topology and the Topology Editor tools in ArcMap; this step was completed to create individual polygons without gaps or overlap. Efforts were made to match colors in the original map legend to the digital product, with the exception of a few features listed in the original key (for example, feature “Pve” does not match the exact color in the plates). Updated colors were selected to ease the distinction between similarly colored features. Saucier envisioned his work to be utilized by engineering geologists conducting studies that were focused at both the local and regional scale in the Lower Mississippi River Valley (Saucier, 1994). Creating a digital dataset of Saucier’s seminal geomorphological work increases the usability of the map layers for current and future scientific investigations focused on regional groundwater availability in the Mississippi Alluvial Plain. References Saucier, R.T., 1994, Geomorphology and Quaternary Geologic History of the Lower Mississippi Valley: U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS, Vols. I and II, 398 p. and 28 plates