Briar Creek is a tributary of the Susquehanna River in Columbia County, Pennsylvania, in the United States.

The rock in the watershed mostly consists of sandstone, siltstone, mudstone, limestone, and shale.

There are Pennsylvania State Game Lands in the watershed, as well as a lake known as the Briar Creek Reservoir.

[3][4] It flows east for a short distance before turning south through a gap in Lee Mountain, briefly descending quite steeply.

The course levels out as it leaves the mountain behind and begins flowing through a valley after a short distance.

Soon afterwards, the stream picks up the tributary West Branch Briar Creek and turns southeast.

The stream then turns southwest and reaches its confluence with the Susquehanna River near French Island.

On West Branch Briar Creek, the temperature is a minimum of 35.6 °F (2.0 °C), a median of 57.38 °F (14.10 °C), and a maximum of 71.6 °F (22.0 °C).

Two miles downstream of East Branch Briar Creek's headwaters, the median temperature is 49.73 °F (9.85 °C) and the range is 32.18 to 71.42 °F (0.10 to 21.90 °C).

Near Briar Creek Reservoir, the water temperature has a minimum of 32.18 °F (0.10 °C), a maximum of 78.62 °F (25.90 °C), and a median of 50.18 °F (10.10 °C).

[2] The watershed of Briar Creek is located in the ridge and valley physiographic region.

[2] In the very northern reaches of the Briar Creek watershed, the bedrock is made up of sandstone.

Places it is found include Briar Creek about two miles downstream of its headwaters.

The Albrights Series, a silt loam with gravel, is also found in the watershed, in such places as East Branch Briar Creek two miles downstream of its headwaters.

The Chenango Series is a silt loam that occurs, among other places, in the southeastern and southern corners of the watershed.

The Zipp Series is a somewhat acidic silt loam that occurs in places such as the Cabin Run watershed.

Its tributary West Branch Briar Creek is about 15 feet (4.6 m) wide.

Much of this is on Knob Mountain or belongs to the Pennsylvania State Game Lands Number 55.

[8] Up to approximately 1770, the area around Briar Creek was inhabited by the Lenni Lenape Indians.

[9] The Briar Creek area was one of the first places in Columbia County to be settled, on account of the high level of fertility of the land.

In 1799, Samuel Ely was granted a patent from the state of Pennsylvania for 307 acres of land on Briar Creek known as "Manheim".

A number of other industries were established in the watershed in the early 1800s, including a sawmill, a woolen mill, an iron furnace, and a tannery.

The Pennsylvania Department of Conservation and Natural Resources has designated the Briar Creek watershed as "place of ecological importance".

Bald eagles, sandhill cranes, and several species of waterfowl have been observed on Briar Creek Reservoir.

Mammals living in the watershed include minks, muskrats, and short-tailed shrews, and the endangered Indiana bat.

The smallest fish were pumpkinseed, of which 12 specimens between two and four inches (five and ten centimeters) were observed.

[12] It was originally constructed to control floods, but most recreational activities in the watershed take place at this lake.