Coal Run is a tributary of Shamokin Creek in Northumberland County, Pennsylvania, in the United States.

The stream is designated as an impaired waterbody due to metals from abandoned mine drainage.

It flows east-southeast through a valley for several tenths of a mile before entering Coal Township.

The stream continues flowing east-southeast for more than a mile before turning south for a short distance.

The stream then flows in a west-northwesterly direction for several tenths of a mile, passing through the census-designated place of Marshalton before entering Shamokin.

The stream then flows west for a few tenths of a mile until it reaches its confluence with Shamokin Creek.

[1] Coal Run joins Shamokin Creek 22.5 miles (36.2 km) upstream of its mouth.

The concentration of water hardness ranged from 224 to 259 milligrams per liter (0.224 to 0.259 oz/cu ft) in the two times it was measured.

[7] In 2000, the concentrations of recoverable sodium and potassium in Coal Run were 97.0 and 2.70 milligrams per liter (0.09689 and 0.00270 oz/cu ft).

[4] In the early 1900s, fine culm was carried into Coal Run via waste water streams from collieries.

In 1828, Daniel Derk opened a mine on Coal Run near a public road that crossed the stream.

Eagle, Inc. requested permission to construct a coal dredging plant on the bank of the stream.

[6] A concrete slab bridge carrying State Route 2026 over Coal Run was built in 1938.

A concrete channel beam bridge carrying State Route 2017 was built over the stream in 1952 and repaired in 2007.

A concrete culvert bridge was built over the stream 2 miles (3.2 km) south of Paxinos in 1970.