The Dennis Johnson Lumber Company Sawmill, also known as the Johnson Mill, was an industrial fixture in Waterboro, Maine from at least 1869 to 1963. Over its long history the mill manufactured long and short lumber, shingles, and wooden box components. In the 19th century it utilized water power from Johnson Stream before upgrading just after the turn of the twentieth century to mechanical power provided by a steam boiler. Although closed since 1963, the mill complex, consisting of the mill building, sluiceway, lumber yard and associated bridge, retains most of its machinery, including the bandsaw, carriage, edger, joiner, associated belts and massive steam boiler. A wing off the building, known as the file room and dedicated to maintaining the nine inch saw blades, still contains the sharpening equipment and spare blades. The Johnson Mill is also significant as one of the few industrial structures to remain in the town from before 1947. As such, the Dennis Johnson Lumber Company Sawmill was recognized by the National Register for its long association with the lumber manufacturing industry in northern York County.