The Río Negro is one of the principal tributaries of the Rahue River in southern Chile, flowing from south to north as it drains part of the eastern slopes of the Cordillera Pelada. The river gives its name to the commune of Río Negro, through which it passes, and its mouth meets the Rahue River at an elevation of approximately 26 meters above sea level.

For paddlers, the river has been used for organized kayak descents promoted by the local tourism office. One documented route runs from Puente Esmeralda downstream to Puente Chapaco, using these two bridges as the put-in and take-out respectively. The river has been characterized by local organizers as presenting minimal complexity, making it accessible to paddlers without advanced whitewater skills, though safety personnel and a qualified kayak instructor have been deployed on organized runs, suggesting that some level of caution is still warranted.

Paddling on the Río Negro has been promoted as a nature-based recreational activity, and the local tourism office has run open participation events on the river. These organized descents have been limited to adults aged 18 and older. No specific restrictions on independent paddling are known.

The river passes through a landscape associated with the coastal precordillera of southern Chile's Los Lagos Region, an area characterized by significant rainfall and dense native vegetation typical of the region.