As part of the Sea level and Storm Impacts on Estuarine Environments and Shorelines project (SSIEES), scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a single-beam bathymetry survey within the estuarine, open bay and tidal creek environments of Grand Bay Alabama/Mississippi, in May-June 2015. The goal of the SSIEES project is to assess the physical controls of sediment and material exchange between wetlands and estuarine environments along the northern Gulf of Mexico, specifically Grand Bay AL/MS and Vermilion Bay, Louisiana, as well as along the US east coast in Chincoteague Bay Virginia/Maryland. The data included in this data release will provide baseline bathymetric information for future research investigating wetland/marsh evolution, sediment transport, recent and long term geomorphic change, and will support modeling of future changes in response to restoration and storm impacts. The survey area encompasses more than 40 square kilometers (km2) of Grand Bay’s incorporated waters. This data release archives processed single-beam bathymetry data, collected from May 28-June 3, 2015 (USGS Field Activity Number [FAN] 2015-315-FA). Geographic information system (GIS) data products include: a 10 and 30-meter cell size interpolated bathymetry grid, trackline maps, and point data files. Additional files include error analysis maps, Field Activity Collection System (FACS) logs, and formal Federal Geographic Data Committee (FGDC) metadata.