The surface of the river is usually frozen from early November to mid-May, but safe circulation on the ice generally occurs from mid-November to the end of April.

The major watersheds adjacent to the Corner River are: The Corner River originates at the mouth of an unidentified lake (length: 2.3 metres (7 ft 7 in); altitude: 269 metres (883 ft)) belonging to a group of lakes identified as "Corner Lakes" in the eastern part of the Cochrane District.

The mouth of this lake of head is located at: From its source, the Corner River runs more or less parallel to the Ontario and Quebec boundary, on 65.2 kilometres (40.5 mi) in the following segments: Corner River empties on the southwestern shore of the Harricana River in front of Low Shoal Island.

This confluence is located at: The hydronyme "River Corner" (English origin) is similar to the fact that the mouth of the river flows into a bend of river facing Low Shoal Island.

Mariners navigating through the Harricana River through the southern part of the island to James Bay were passing by the river bend.