Kehly Run begins in Fetter Pond in West Mahanoy Township. It flows west for several hundred feet, passing through another pond and entering Number Six Reservoir. From the southern end of this reservoir, the stream turns south-southeast for several tenths of a mile, passing near Number Five Reservoir, crossing Pennsylvania Route 924, and entering a valley. In this valley, the creek flows in a generally southerly direction for several tenths of a mile, passing through Kehly Run Reservoir Number Three and Number Two Reservoir. Towards the lower reaches of this valley, in West Mahanoy Township, or possibly at or shortly after its end, in Shenandoah, the stream reaches its confluence with or becomes Shenandoah Creek. Kehly Run joins Shenandoah Creek upstream of its mouth.
Hydrology
Kehly Run is designated as an impaired waterbody. The stream is impacted by abandoned mine drainage. However, it has been described as having "very good" water quality at site S11, in its upper reaches. In the late 1800s, the stream was described as having once been a stream of "good, soft, pure mountain water". In March 2001, the discharge of Kehly Run was measured to be, while in August 2001, it was. The dissolved oxygen concentration was in March and August 2001, respectively. In March 2001, the pH was 4.7 and the net alkalinity concentration was, while in August 2001, the pH was 4.8 and the net alkalinity concentration was. The concentration of dissolved aluminum in Kehly Run was in March 2001 and in August 2001. The dissolved manganese and iron concentrations in the stream were in March and in August. In March 2001, the concentration of dissolved nitrate in Kehly Run was less than, while the concentration in August 2001 was. The concentration of dissolved phosphorus was less than in both March and August 2001. The sulfate concentration was in March and August 2001, respectively.
Geography and geology
The elevation of the source of Kehly Run is above sea level. The stream is situated entirely within the Western Middle Anthracite Field. There is some abandoned mine land in the vicinity of the stream's upper reaches. The dried sediment of Kehly Run was light olive brown in the Munsell color system. A dam known as the Kehly Run Dam No. 3 is, about high, and is made of earth and rockfill. In 1980, the dam was judged to be in fair condition. There are three reservoirs further upstream and one pool further downstream.
Watershed
The watershed of Kehly Run has an area of. The stream is entirely within the United States Geological Survey quadrangle of Shenandoah. The watershed of Kehly Run occupies a total of approximately 1 percent of the Mahanoy Creekdrainage basin. The watershed is located near the northeastern corner of the Shenandoah Creek watershed and in the upper part of the Mahanoy Creek watershed.
In 2001, no fish were observed in Kehly Run near Shenandoah, but macroinvertebrates were observed. A total of ten macroinvertebrate taxa were observed. Hydropsychidae was classified as "abundant", with 25 to 100 individuals being observed. Leuctridae and Simuliidae were classified as "common", with 10 to 24 individuals being observed. The taxa Cordulegastridae and Crydalidae were classified as "present", with three to nine individuals being observed. Another several taxaAeshnidae, Calopterygidae, Tipulidae, Cambaridae were "rare", with only one or two individuals of each being observed. A small number of miscellaneous individuals from Diptera were observed. Second-growth forest occurs in the vicinity of some reaches of Kehly Run. The family-level Hilsenhoff Biotic Index value of the stream was 4.14. Historically, Kehly Run was used as a trout-fishing stream. The stream is classified as a Coldwater Fishery.
