Long Run is a

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainag ...

of Elk Run in

Sullivan County, Pennsylvania Sullivan County is a county in the Commonwealth of Pennsylvania. It is part of Northeastern Pennsylvania. As of the 2020 census, the population was 5,840, making it the second-least populous county in Pennsylvania. Its county seat is Laporte ...

, in the United States. It is approximately long and flows through Davidson Township. The stream's watershed has an area of . It has no named tributaries, but four unnamed tributaries. The stream is considered by the

Pennsylvania Department of Environmental Protection The Pennsylvania Department of Environmental Protection (DEP) is the agency in the U.S. state of Pennsylvania responsible for protecting and preserving the land, air, water, and public health through enforcement of the state's environmental laws. ...

to be impaired by atmospheric deposition and metals. Wisconsinan Bouldery Till, Wisconsinan Till, and bedrock consisting of sandstone and shale occur in the vicinity of it.

Course

Long Run begins at the top of a deep valley in Davidson Township. It flows south for several tenths of a mile, receiving two unnamed tributaries from the

left Left may refer to: Music * ''Left'' (Hope of the States album), 2006 * ''Left'' (Monkey House album), 2016 * "Left", a song by Nickelback from the album ''Curb'', 1996 Direction * Left (direction), the relative direction opposite of right * L ...

. The stream then turns south-southwest and its valley becomes considerably deeper. It then turns south for more than a mile, receiving two more unnamed tributaries from the left. The stream then turns southwest, exits its valley, and reaches its confluence with Elk Run near the border between Sullivan County and Columbia County. Long Run joins Elk Run upstream of its mouth.

Hydrology

Long Run is considered to be impaired by

atmospheric deposition In the physics of aerosols, deposition is the process by which aerosol particles collect or deposit themselves on solid surfaces, decreasing the concentration of the particles in the air. It can be divided into two sub-processes: ''dry'' and '' ...

and

metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typi ...

s. A total of of the stream and its unnamed tributaries have this impairment. This is approximately 10.5 percent of all the impaired streams in the watersheds of West Branch Fishing Creek and

East Branch Fishing Creek East Branch Fishing Creek is a tributary of Fishing Creek in Columbia County and Sullivan County, Pennsylvania, in the United States. It is long. The stream and its tributaries are acidic and contain aluminum. The area in the vicinity was firs ...

. Long Run does not attain the stream standards of the

. None of its four unnamed tributaries attain the standards either.

Geography and geology

The elevation near the

mouth In animal anatomy, the mouth, also known as the oral cavity, or in Latin cavum oris, is the opening through which many animals take in food and issue vocal sounds. It is also the cavity lying at the upper end of the alimentary canal, bounded on t ...

of Long Run is above

sea level Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardise ...

. The elevation of the stream's

source Source may refer to: Research * Historical document * Historical source * Source (intelligence) or sub source, typically a confidential provider of non open-source intelligence * Source (journalism), a person, publication, publishing institute ...

is between above sea level. Most of the valley of Long Run is on a glacial or resedimented

till image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is d ...

known as the Wisconsinan Bouldery Till. This till contains numerous

boulder In geology, a boulder (or rarely bowlder) is a rock fragment with size greater than in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive. In ...

s consisting of

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...

quartz Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical ...

, and

conglomerate Conglomerate or conglomeration may refer to: * Conglomerate (company) * Conglomerate (geology) * Conglomerate (mathematics) In popular culture: * The Conglomerate (American group), a production crew and musical group founded by Busta Rhymes ** C ...

. The rest of the stream's valley, as well as the slopes of the valley, are on

bedrock In geology, bedrock is solid rock that lies under loose material ( regolith) within the crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of be ...

consisting of

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especia ...

and sandstone. A till known as the Wisconsinan Till occurs near the headwaters of the stream.

Watershed

The

watershed Watershed is a hydrological term, which has been adopted in other fields in a more or less figurative sense. It may refer to: Hydrology * Drainage divide, the line that separates neighbouring drainage basins * Drainage basin, called a "watershe ...

of Long Run has an area of . The stream is entirely within the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

quadrangle of Elk Grove. Long Run is one of twenty streams in the Upper Susquehanna-Lackawanna drainage basin whose

streambed A stream bed or streambed is the bottom of a stream or river (bathymetry) or the physical confine of the normal water flow ( channel). The lateral confines or channel margins are known as the stream banks or river banks, during all but flood ...

is publicly owned. The streambeds of the two other named tributaries of Elk Run (Hog Run and Gallows Run) are also publicly owned, as is the streambed of Elk Run itself.

History

Long Run was entered into the

Geographic Names Information System The Geographic Names Information System (GNIS) is a database of name and locative information about more than two million physical and cultural features throughout the United States and its territories, Antarctica, and the associated states of ...

on August 2, 1979. Its identifier in the Geographic Names Information System is 1179887.

References