The creek is a High-Quality Coldwater Fishery and Class A Wild Trout Waters in some places.

The creek has been surveyed at least nine times by the Pennsylvania Fish and Boat Commission.

Little Catawissa Creek begins in a narrow valley in Conyngham Township.

Approximately a mile downstream, it receives its first named tributary, Trexler Run.

After some distance, it begins meandering northeast for a few miles, receiving the tributary Stony Run.

Shortly afterwards, the creek turns north-northeast, crosses into North Union Township again.

A few tenths of a mile downstream, it reaches its confluence with Catawissa Creek.

[4] Stony Run joins Little Catawissa Creek 1.96 miles (3.15 km) upstream of its mouth.

Trexler Run joins Little Catawissa Creek 4.24 miles (6.82 km) upstream of its mouth.

[3] Little Catawissa Creek is infertile in its upper reaches, from its headwaters to T431, 8.10 miles (13.04 km) upstream of its mouth.

[2] At 1:00 P.M. on June 26, 1997, the air temperature in the vicinity of Little Catawissa Creek 8.90 miles (14.32 km) upstream of its mouth was 28 °C (82 °F).

[2] The specific conductivity of the waters of Little Catawissa Creek is 80 micro-mhos 8.90 miles (14.32 km) upstream of its mouth.

[1] Little Catawissa Creek flows over rock of the Mauch Chunk Formation for its entire length.

A substantial area of the Pocono Formation can be found in the northwestern part of the watershed and large areas of rock of the Pottsville Formation occupy portions of the southern and western parts of the watershed.

[4] Little Catawissa Creek is flanked by areas prone to flooding between the point where it enters Schuylkill County and its mouth.

[2] There is a flooded strip mine in the western part of the watershed of Little Catawissa Creek.

Additionally, Pennsylvania Route 42 traverses the western edge of the creek's watershed.

[2] In 1990, the population density of the upper reaches of the watershed of Little Catawissa Creek was 30 people per square kilometer.

The population density in the middle reaches of the creek's watershed was 40 people per square kilometer and the density in the lower reaches of the watershed was 31 people per square kilometer.

[2][4] The main areas of residential development in the watershed are the communities of Aristes and Ringtown.

The Pennsylvania Department of Environmental Protection has issued four mining permits in the watershed of the creek.

[2] Little Catawissa Creek is on the United States Geological Survey quadrangles of Ashland, Shenandoah, and Nuremberg.

[7] John Mourey constructed a sawmill and gristmill on Little Catawissa Creek 0.5 miles (0.80 km) west of Ringtown in 1853.

[9] Little Catawissa Creek is considered by the Pennsylvania Department of Environmental Protection to be a High-Quality Coldwater Fishery between its headwaters and Reservoir Road.

The upper reaches of the creek, between its headwaters and a point slightly downstream of where it enters Schuylkill County are considered by the Pennsylvania Fish and Boat Commission to be Class A Wild Trout Waters and the rest of the creek's length is considered to be Approved Trout Waters.

[2] The tributary Trexler Run is also considered to be Class A Wild Trout Waters throughout its length.

However, introducing rainbow trout into the creek is forbidden, although they were historically stocked there by the Pennsylvania Fish and Boat Commission.

Eight fish species, including brown trout, were observed on the creek between T435 and its mouth during a 1976 survey.

[2] The biomass of wild trout in Little Catawissa Creek upstream of T431 is 30.85 kilograms per hectare (27.52 lb/acre).