It is known for The Trait de Scie (Saw Cut),[5] a deep canyon 8 metres (26 ft) wide with several rapids and small waterfalls that are passed by the salmon heading up the river.

The current has scoured out large cavities in the pink granite river bed, which are called "giant cooking pots".

[6] In its natural state, the Le Trait de Scie canyon[5] is classified as an impassable obstacle for Atlantic salmon.

Starting among the sphagnum-rich bogs of the Labrador–Quebec plateau, the unassuming river quickly gains momentum as it wathefalls off the ancient Laurentian mountain range through an array of commanding canyons, magnificent drops, and glacial landforms (i.e., eskers, drumlins and kames).

[3] The Dictionary of rivers and lakes of the province of Quebec (1914)[11] says Agwanus or Agouanus is a Montagnais word that means "where one unloads" boats.

Another theory is it comes from the Innu word akuannis meaning a beaver scooping mud from the river bottom to build its lodge.

Saucier, Robitaille, Grondin, Bergeron, 1998 The river has been open to recreational fishing since 1988, the most sought after takes are: The Innu of Natashquan have exclusive rights to the 4 kilometres (2.5 mi) stretch from the mouth to the Trait-de-Scie.

The only significant amount of good habitat is upstream from kilometre 137, including the Aguanish North River.

In view of the rapidly declining Atlantic salmon population catch-and-release should have been implemented on all rivers apart from northern Quebec.