This portion of the data release presents sediment grain-size data from samples collected from Anahola Valley, Kaua`i, Hawai`i in November, 2015 (USGS Field Activity 2015-671-FA). 63 sand and mud samples were taken from sediment cores that were collected using a Russian corer (a hand-held, side-filling peat auger) from two site locations. Site locations were determined using a hand-held global navigation satellite system, GNSS. The grain-size distributions of samples were determined using standard techniques developed by the USGS Pacific Coastal and Marine Science Center sediment lab. The grain-size data are provided in a comma-delimited spreadsheet (.csv). Core ANA15-RC1 BR contained two carbonate sand layers (Sand A1from 24.5-29 cm depth and Sand A2 from 32-35 cm depth). Core ANA15-RC6 BR contained a deeper carbonate sand layer (Sand A3 96-114 cm depth).