Mile Run is a tributary of White Deer Creek in Union County, Pennsylvania, in the United States. It is approximately 1.9 miles (3.1 km) long and flows through West Buffalo Township. The watershed of the stream has an area of 1.57 square miles (4.1 km2). It has been described as a "spring run". Wild trout naturally reproduce within the stream and numerous bryophyte species have been observed in its vicinity.

White Deer Creek is a tributary of the West Branch Susquehanna River in Centre County and Union County, in Pennsylvania, in the United States. It is approximately 28 miles (45 km) long and flows through Miles Township in Centre County and Hartley Township, Lewis Township, West Buffalo Township, and White Deer Township in Union County. The watershed of the creek has an area of 45.1 square miles (117 km2). Parts of the creek are designated as impaired. The creek's discharge near White Deer can be as low as 3 cubic feet per second (0.085 m3/s) or as high as 169 cubic feet per second (4.8 m3/s).