Long Run

Long Run is a tributary of Elk Run in Sullivan County, Pennsylvania, in the United States. It is approximately long and flows through Davidson Township. The stream's watershed has an area of . It has no named tributaries, but four unnamed tributaries. The stream is considered by the Pennsylvania Department of Environmental Protection to be impaired by atmospheric deposition and metals. Wisconsinan Bouldery Till, Wisconsinan Till, and bedrock consisting of sandstone and shale occur in the vicinity of it. Course Long Run begins at the top of a deep valley in Davidson Township. It flows south for several tenths of a mile, receiving two unnamed tributaries from the left. The stream then turns south-southwest and its valley becomes considerably deeper. It then turns south for more than a mile, receiving two more unnamed tributaries from the left. The stream then turns southwest, exits its valley, and reaches its confluence with Elk Run near the border between Sullivan County and Columbia County. Long Run joins Elk Run upstream of its mouth. Hydrology Long Run is considered to be impaired by atmospheric deposition and metals. A total of of the stream and its unnamed tributaries have this impairment. This is approximately 10.5 percent of all the impaired streams in the watersheds of West Branch Fishing Creek and East Branch Fishing Creek.