A bathymetric survey of Gillham Lake, Arkansas, was conducted in late June 2018 by the Lower Mississippi-Gulf Water Science Center of the U.S. Geological Survey (USGS) using methodologies for sonar surveys like those described by Wilson and Richards (2006) and Richards and Huizinga (2018). Data from the bathymetric survey were combined with data from an aerial Light Detection And Ranging (LiDAR) survey conducted in 2016 by the National Resources Conservation Service (U.S. Geological Survey, 2017) to create a digital elevation model (DEM) of the extent of the flood pool of the lake and compute volume (storage capacity) of the lake at 1-foot increments in water surface elevation from 431-559 feet (ft) above the North American Vertical Datum of 1988 (NAVD88) and for conservation pool elevation 502.1 ft and flood pool elevation 569.1 ft. Products in this data release are stored within an Esri file geodatabase and include: 1) point datasets of the bathymetric and LiDAR surveys; 2) point data representing the stream channels of select tributaries where bathymetric data were sparse, digitized from historical topographic maps; 3) clipping polygons representing the extent of the LiDAR data the and flood pool; 4) Two DEMs, one representing the extent of the LiDAR data used in the study and the other representing the extent of the flood pool; 5) bathymetric contours at 10-ft intervals, derived from the DEM of the extent of the LiDAR and clipped to the extent of flood pool; and 6) a table of volume (storage capacity) of the lake. A third DEM, representing the extent of the LiDAR, is provided in GeoTIFF format for use with softwares other than Esri ArcGIS. In April 2019, it was discovered that some of the areas in shallow and/or tree-ridden areas of the lake that had not been surveyed needed additional data in order to generate a more topographically realistic surface. Additional data were interpolated from a combination of elevation data from pre-impoundment topographic maps and from the point datasets of the bathymetric and LiDAR surveys. The interpolated data was added to the geodatabase, the final products re-created, metadata edited accordingly, and the data release reviewed. In response to the second review, a vertical datum discrepancy between the single beam and multi-beam bathymetric datasets was addressed and select areas of erroneous bathymetric data were edited. First release: October 2018; revised April 2020 (version 1.1). The previous version can be obtained by contacting the USGS Lower Mississippi-Gulf Water Science Center using the "Point of Contact" link on the landing page on ScienceBase. References: Richards, J.M. and Huizinga, R.J., 2018, Bathymetric contour map, surface area and capacity table, and bathymetric difference map for Clearwater Lake near Piedmont, Missouri, 2017: U.S. Geological Survey Scientific Investigations Map 3409: 1 sheet, https://doi.org/10.3133/sim3409; U.S. Geological Survey, 2017, Lidar Point Cloud - USGS National Map 3DEP Downloadable Data Collection: U.S. Geological Survey, https://nationalmap.gov/3DEP; Wilson, G.L., and Richards, J.M., 2006, Procedural Documentation and Accuracy Assessment of Bathymetric Maps and Area/Capacity Tables for Small Reservoirs: U.S. Geological Survey Scientific Investigations Report 2006-5208, https://pubs.usgs.gov/sir/2006/5208/.