Hallowing Run is a tributary of the Susquehanna River in Northumberland County, Pennsylvania, in the United States. It is approximately long and flows through Lower Augusta Township. The watershed of the stream has an area of. The stream is not designated as an impaired waterbody. It is a stream of "local importance" according to History of Northumberland County, Pennsylvania, and is located between Little Mountain and the Shamokin Hills. The area in its vicinity was settled by the first half of the 1800s and several bridges have been constructed over the stream. Its watershed is designated as a Warmwater Fishery and a Migratory Fishery.
Course
Hallowing Run begins in a small valley in Lower Augusta Township. It flows north for a few tenths of a mile and enters a much larger and deeper valley. Here, the stream flows north-northwest for a short distance before turning west-southwest for a few miles. In this reach, it flows through the valley alongside Hallowing Run Road and receives several unnamed tributaries: seven from the and three from the. The stream then turns south-southwest and its valley narrows. It begins flowing alongside Pennsylvania Route 147. Several tenths of a mile further downstream, it leaves its valley and turns west. The stream then crosses Pennsylvania Route 147 and a railroad and reaches its confluence with the Susquehanna River. Hallowing Run joins the Susquehanna River upriver of its mouth.
Hydrology
Hallowing Run is not designated as an impaired waterbody.
Geography and geology
The elevation near the mouth of Hallowing Run is above sea level. The elevation of the stream's source is between above sea level. A total of 125 tons of riprap were once placed along of Hallowing Run. Dark olive rocks of the Chemung Formation occur in the vicinity of the stream's mouth. Hallowing Run was described as a stream of "local importance" in J.J. John's 1891 book History of Northumberland County, Pennsylvania. It is situated between the Shamokin Hills and Little Mountain.
Hallowing Run was entered into the Geographic Names Information System on August 2, 1979. Its identifier in the Geographic Names Information System is 1176401. The stream is also known as Hollowing Run. This name appears in Israel C. White's 1883 book The geology of the North Branch Susquehanna River Region in the six counties of Wyoming, Lackawanna, Luzerne, Columbia, Montour and Northumberland. By the early to mid 1800s, the area in the vicinity of Hallowing Run was somewhat settled, with farms, mills, and a small number of schoolhouses. A roadway known as Hallowing Run Road also passed through the area, connecting with the Harrisburg Road and the Tulpehocken Road. Many of the early settlers in the area were Scotch-Irish. A Mr. DeWitt constructed a mill from Sunbury in 1840 and used Hallowing Run as a power source. A steel stringer/multi-beam or girder bridge carrying Township Road T-394 over Hallowing Run in 1904. It is located south of Sunbury and is long. A concrete tee beam bridge carrying State Route 4020 over the stream was built in the village of Asherton in 1921. This bridge is long. A steel stringer/multi-beam or girder bridge carrying the same road over Hallowing Run was built in 1973. It is long and is located west of Augustaville. At least one wooden covered bridge historically crossed Hallowing Run.
