A significant part of the land in the creek's watershed is forested, with large areas being owned by the Pennsylvania Bureau of Forestry.

It flows east through its relatively deep, narrow valley for more than a mile before receiving its first named tributary, Tunis Run, from the right.

The creek then begins flowing east-northeast again, now fairly close to Interstate 80, and receives the tributary Mile Run from the left and passing Little Mountain.

The creek heads east for several tenths of a mile before receiving Lick Run, its last named tributary, from the left.

For the next several miles, the creek heads in a generally easterly direction between South White Deer Ridge and Catharines Crown/Nittany Mountain, still alongside Interstate 80.

[1] White Deer Creek joins the West Branch Susquehanna River 15.76 miles (25.36 km) upstream of its mouth.

At some points, the valley walls rise steeply almost immediately from the creek's streambanks, which made the construction of roads through those areas difficult.

A 4-foot (1.2 m) dam for water supply is located on White Deer Creek a few miles upstream of Interstate 80.

[10] In the lowlands of the White Deer Creek watershed, coarse-grained soils are predominant; sand, silt, gravel, and boulders are common.

The Pennsylvania Bureau of Forestry owns the vast majority of the land in the creek's watershed upstream of the dam.

[19] An overhead power line, a compressed natural gas pipeline, on-lot wastewater systems, and unpaved roads are present in the watershed of White Deer Creek.

[21][22] White Deer Creek's name comes from the Delaware word Woap'-achtu-hanne, meaning "white-deer stream".

[24] The widow Catharine Smith began building a sawmill and a gristmill on White Deer Creek in 1774 and completed the construction in 1775.

These included Daniel Caldwell's stone gristmill, fulling mill, sawmill, carding machine, and distillery.

John McCall, a native of Scotland, established a camp in the upper reaches of the watershed by 1860 and used splash dams to float the logs downstream to his mill.

Ario Pardee later established a system to float them all the way to the mouth of White Deer Creek, where they were ferried to Watsontown for milling.

[27] Near the turn of the 20th century, the Kulp Lumber Mill processed millions of board feet of timber taken from White Deer Creek and Spruce Run via a narrow gauge railway system.

[15] It was incorporated by the White Deer Lumber Company on April 26, 1906 and ran as far as Loganton, a distance of 24 miles (39 km).

A two-span prestressed box beam or girders bridge carrying State Route 1003 over the creek was built in 1958 and repaired in 2011.

A prestresed box beam or girders bridge carrying State Route 1011 over the creek in White Deer was built in 1963 and is 89.9 feet (27.4 m) long.

A two-span steel stringer/multi-beam or girder bridge was built across the creek 0.2 miles (0.32 km) northeast of White Deer in 1974 and is 68.9 feet (21.0 m) long.

[30] Wild trout naturally reproduce in the creek from its headwaters downstream to the White Deer Dam, a distance of 18.40 miles (29.61 km).

[12] Forests and dense areas of mountain laurel occupy most of the valley of White Deer Creek in some reaches.

The Union County Natural Areas Inventory recommended maintaining a forested riparian buffer around the creek.

By the late 1930s, second-growth trees including hardwoods, hemlocks, pines, and aspens, grew in the watershed, some of them up to 1 foot (0.30 m) in diameter.

This allowed wealthier residents of Lewisburg, Milton, Sunbury, Watsontown, and Williamsport to construct weekend/vacation cabins in the watershed.

[12] At least 17.1 miles (27.5 km) of White Deer Creek is navigable by canoe during rapid spring snowmelt or within five days of heavy rain.

[10][32] However, it is not nationally known, possibly due to its small size and the fact that the Delayed Harvest Fly-Fishing Only reach is in remote a location.

[10] It is classified as Approved Trout Waters by the Pennsylvania Fish and Boat Commission from Cooper Mill Road downstream to the creek's mouth.

[11] Mid Penn Trailblazers' marathon Dam Full crosses the headwaters of White Deer Creek at between 15.5 and 18.0 miles (24.9 and 29.0 km).