Spring Brook is a tributary of the Lackawanna River in Lackawanna County and Luzerne County, in Pennsylvania, in the United States. It is approximately 17 miles (27 km) long and flows through Covington Township, Spring Brook Township, and Moosic in Lackawanna County and Pittston Township in Luzerne County. The watershed of the stream has an area of 57.2 square miles (148 km2). It is designated as a High-Quality Coldwater Fishery and a Migratory Fishery above Interstate 476 and as a Coldwater Fishery and a Migratory Fishery below it. A section is also designated as Class A Wild Trout Waters. The stream's tributaries include Panther Creek, Plank Bridge Creek, Rattlesnake Creek, Green Run, Monument Creek, and Covey Swamp Creek. It has a relatively high level of water quality and is very slightly acidic, with a pH of 6.4 to 6.9.