The massive Grandes or Coulonge Chutes, with a height of 48 meters (157 ft), is approximately 15 kilometers (9.3 mi) upstream of the confluence with the Ottawa River.

[1] The Coulonge was used as a waterway by native North Americans and, later, by the coureurs des bois plying their independent trade in furs.

In 1843, Bryson built a sawmill near the mouth of the river, which led to permanent settlement and the formation of the village of Fort-Coulonge.

[10] For almost 150 years, the forests around the Coulonge were logged throughout the winter months until spring breakup permitted the massive log drives which, along with similar operations throughout the Ottawa River watershed, fueled the economy of the Ottawa Valley region from the early 19th century through the middle of the 20th.

[11] Since then, the timber from smaller-scale logging operations has been hauled out by trucks over a network of dirt roads which meander throughout the Coulonge River valley.