This data set contains information on well yield and ancillary information at 7,287 wells in the bedrock aquifer in the Nashoba terrane in central and eastern Massachusetts. Well yield was compiled from records in databases and files of the Massachusetts Department of Environmental Protection and U.S. Geological Survey. Ancillary data include well depth; bedrock geology, surficial geology, topographic setting, and wetlands at the well location; distance of the well to hydrologic and geologic features; and distance of the well to lineaments. The data in this data release were interpreted in U.S. Geological Survey Scientific-Investigations Report 2012-5155.