Leggetts Creek is considered to be impaired due to urban development problems, but is not affected by acid mine drainage.

From the southwestern end of the reservoir, the creek flows southwest for more than a mile before turning south-southwest and crossing Interstate 81.

[1] Leggetts Creek reaches its confluence with the Lackawanna River 14.36 miles (23.11 km) upriver of its mouth.

[4] Leggetts Creek is considered by the Pennsylvania Department of Environmental Protection to be impaired due to urban development problems.

[5] It is possible that Leggetts Creek sometimes exceeds its total maximum daily load, especially during low flow conditions and the summer months.

[8] The peak annual discharge of Leggetts Creek near its mouth has a 10 percent chance of reaching 2180 cubic feet per second.

[9] The peak annual discharge of Leggetts Creek at Neary Place (Mary Street) has a 10 percent chance of reaching 2470 cubic feet per second.

The peak annual discharge of the creek at the border between Scranton and South Abington Township has a 10 percent chance of reaching 2130 cubic feet per second.

[1] During a 2013 fish population survey, the average stream width of the creek was found to be approximately 18 feet (5.5 m).

[4][6] However, in some parts of the creek's lower reaches, fill has been dumped onto its banks, creating steep slopes.

[9] There are waterfalls and cascades on a reach of Leggetts Creek from the Griffin Reservoir to an intake dam three quarters of a mile downstream.

[6] At Providence, the creek flowed directly southeast prior to the glacial period, reaching the Lackawanna River approximately 0.5 miles (0.80 km) downstream of its current location.

From this point downstream to its mouth, it flows through a rocky channel that contains a thick covering of till on its upper walls.

[14] A rock formation known as the Campbell's Ledge Black Shale occurs in the vicinity of Leggetts Creek.

[15] The ledge on the northern bank of the creek was in the early 1900s noted to contain a large mass (up to a million tons) of sandy till.

[16] Major land uses in the watershed of Leggetts Creek include high-density residential, neighborhood commercial, and open space.

[4] The creek and the reservoir serve as a supplemental drinking water supply for more than 100,000 people as of the late 20th century.

[19] Thomas Meredith conceived the idea of a railroad going from the mouth of the creek at Providence to the Great Bend on the Susquehanna River, a distance of 48 miles (77 km), in 1826.

A masonry arch bridge with a length of 34.1 feet (10.4 m) carries North Main Street over the creek.

In 1979, a 37.1-foot-long prestressed box beam or girders bridge was built; it carries Mary Street across the creek.

[24] In 1991, the Lackawanna River Corridor Association gathered data on the water chemistry and biological habitats of Leggetts Creek.

[6] In 2012, the South Abington Sewer Authority began upgrading its sewage treatment plant to prevent wastewater and nutrient pollution from entering the creek.

PA Trout Unlimited's AMD Technical Assistance Program conducted a survey of the fish population in the creek on November 15, 2013.

[5] The Lackawanna Valley Conservancy once received a $190,000 Growing Greener grant for the Leggetts Creek Greenway.

[25] Historic places in the watershed of Leggetts Creek include Griffins Mills, which are in South Abington.

[5] In the fishery survey of Leggetts Creek, brown trout and cutlips minnow were the only common species.

From the reservoir downstream to an intake pond near Interstate 81, the creek's riparian buffer contains old growth forest, including tulip poplar trees.

In addition to tulip popular, hemlock and pine also occur in the Griffin Mills reach of the creek.

[6] At three sites on Leggetts Creek, the EPT (Ephemeroptera, Plecoptera, and Trichoptera) Taxa Richness ranges from 4.00 to 6.00.

[5] A greenway and/or connecting trail along Leggetts Creek was proposed in the Lackawanna River Watershed Conservation Plan in the early 2000s.