Fish Dam Run is a long second-order tributary to West Branch Susquehanna River. This is the only stream of this name in the United States.
Fish Dam Run rises about southwest of Renovo, Pennsylvania in Clinton County and then flows northeast to meet West Branch Susquehanna River about 4 miles southwest of Renovo.
Fish Dam Run drains of area, receives about of precipitation, and is about 96.77% forested.