Dunkle Run is a long 2nd order tributary to Brush Run in Washington County, Pennsylvania, United States.
According to the Geographic Names Information System, it has also been known historically as:
Dunkle Run rises about 1 mile northwest of Buffalo, Pennsylvania, in Washington County and then flows southwest to join Brush Run about 0.5 miles northeast of Acheson.
Dunkle Run drains of area, receives about 40.0 in/year of precipitation, has a wetness index of 318.15, and is about 45% forested.