| Calvin Run | |
| Name Other: | Tributary to Dunkard Creek |
| Map Size: | 300 |
| Pushpin Map: | USA Pennsylvania#USA |
| Pushpin Map Size: | 300 |
| Pushpin Map Caption: | Location of Calvin Run mouth |
| Pushpin Map Alt: | Map of Calvin Run mouth location |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | Pennsylvania |
| Subdivision Type3: | County |
| Subdivision Name3: | Greene County |
| Length: | 4.18miles[1] |
| Discharge1 Location: | Dunkard Creek |
| Discharge1 Avg: | 8.02cuft/s at mouth with Dunkard Creek[2] |
| Source1: | Whiteley Creek divide |
| Source1 Location: | about 1.25 miles south of Kirby, Pennsylvania[3] |
| Source1 Coordinates: | 39.7853°N -80.1117°W[4] |
| Source1 Elevation: | 1180feet |
| Mouth: | Dunkard Creek |
| Mouth Location: | about 0.25 miles northeast of Mount Morris, Pennsylvania |
| Mouth Coordinates: | 39.7447°N -80.0614°W |
| Mouth Elevation: | 900feet |
| Progression: | generally southeast |
| River System: | Monongahela River |
| Tributaries Left: | North Branch Calvin Run Watkins Run |
| Tributaries Right: | unnamed tributaries |
| Bridges: | US 19, Haines Hill Road, US 19, I-79, Dooley Run Road |
Calvin Run is a 1.63miles long first-order tributary to Dunkard Creek in Greene County. This is the only stream of this name in the United States.
Calvin Run rises about 1.25 miles south of Kirby, Pennsylvania, and then flows southeasterly to join Dunkard Creek about 0.25 miles northeast of Mount Morris, Pennsylvania.[3]
Calvin Run drains of area, receives about 43.1 in/year of precipitation, and is about 76.8% forested.[2]