Peirce Mill became famous as the only 19th century gristmill operating full time in the NPS system. The site operated off and on until April 1993 when it was determined that the wooden waterwheel and attached mechanical components were too deteriorated to run safely. As a result, Peirce Mill ceased operating. Currently the Friends of Peirce Mill are working with Rock Creek Park to raise the needed funds and supply volunteer help to preserve the mill. Until then, Peirce Barn remains open to the public as a museum and ranger contact station.