This project is a collaborative effort between the U.S. Geological Survey (USGS), U.S. Army Corps of Engineers (USACE), and the state of Alabama funded by the National Fish and Wildlife Foundation (NFWF) to investigate viable, sustainable restoration options that protect and restore the natural resources of Dauphin Island, Alabama. Scientists from the USGS, St. Petersburg Coastal and Marine Science Center collected push cores and water quality data from the marshes of Dauphin Island, Little Dauphin Island, and Cedar Key, Alabama in August, 2015 (U.S. Geological Survey Field Activity Number (FAN) 2015-322-FA; referred to as 15BIM09) as well as in April, 2013 (13BIM01). Sample sites varied between high marshes, low salt marshes, and sand flats. This report serves as an archive for the sedimentological and geochemical data derived from the marsh cores and select surface data from the corresponding marsh core sites collected in August, 2015 (15BIM09). Downloadable data are available and include Excel spreadsheets, JPEG files, and formal Federal Geographic Data Committee metadata. For further information regarding data collection and/or processing methods refer to USGS OFR Ellis and others 2017–1165 (https://doi.org/10.3133/OFR20171165), and Data Series Ellis and others 2017–1046 (https://doi.org/10.3133/DS20171046).