It flows approximately 12 km (7.5 mi) and is a major tributary of the Pawcatuck River.

[3] The river is formed by the confluence of the Queen River and Glen Rock Brook, just above the village of Usquepaug.

Below is a list of all crossings over the Usquepaug River.

The list starts at the headwaters and goes downstream.

Chickasheen Brook is the Usquepaug River's only named tributaries, though it has many unnamed streams that also feed it.