Plum Run is a long 2nd order tributary to Tenmile Creek in Washington County, Pennsylvania.
Plum Run rises about 0.5 miles west-southwest of Beallsville, Pennsylvania, and then flows south to join Tenmile Creek about 0.5 miles southeast of Fairfield.
Plum Run drains of area, receives about 40.9 in/year of precipitation, has a wetness index of 324.20 and is about 53% forested.