Río Negro (Uruguay)

river in Uruguay
Coordinates: 33°25′34″S 58°24′32″W / 33.42611°S 58.40889°W / -33.42611; -58.40889

The Río Negro (Black River) is the most important river in Uruguay.is a river in central France. It is a left tributary of the Uruguay river. It starts in southern Brazil and flows west across the entire width of Uruguay to the Uruguay River.

Río Negro
The Río Negro river at Paso del Puerto
The Río Negro river at Paso del Puerto.
Countries  Brazil,  Uruguay
 - left
 - right Tacuarembó
 - location Bagé, Rio Grande do Sul, Brazil
 - coordinates 33°25′34″S 58°24′32″W / 33.42611°S 58.40889°W / -33.42611; -58.40889
Confluence Uruguay
 - coordinates 33°25′34″S 58°24′32″W / 33.42611°S 58.40889°W / -33.42611; -58.40889
Length 750 km (466 mi)
Basin 70,714 km² (27,303 sq mi)
Discharge for Palmar Dam
 - average 722 /s (25,497 cu ft/s)
Course of the Río Negro river
Course of the Río Negro river
Wikimedia Commons: Rio Negro, Uruguay

The course of the Río Negro across Uruguay effectively divides the south of the country from the north.


The Río Negro is 750 kilometres (466.0 miles) long. Its drainage basin covers 70,714 km2 (27,303 sq mi), most of it in territory of Uruguay; only 2,500 km2 (965 sq mi) are in Brazil.

Its average yearly discharge (volume of water which passes through a section of the river per unit of time) is 226 m3/s (8,000 cu ft/s) (70 years) at the Palmar dam, 72 km (45 mi) to the east of the city of Mercedes, Soriano department.[1]

Average monthly discharge (m3/s) at Palmar


The Río Negro starts in the Bagé municipality, Rio Grande do Sul state, Brazil. It flows from northeast to southwest through Uruguay and divides the country in two parts: the northern part with 6 departments and the southern part (slightly larger) with the 13 remaining departments.

Its course forms the border of the departments:

At its end, to the south of the city of Fray Bentos in the Río Negro department, the Río Negro flows into the Uruguay river as a left tributary. The river has many meanders along its course and three hydroelectric dams has been built on this river that form three artifical lakes (or reservoirs in this case), from northeast to southwest:

  1. Rincón del Bonete Reservoir, also called the Gabriel Terra Reservoir or the Río Negro Reservoir;
  2. Baygorria Dam; and the
  3. Palmar or Constitution Dam.

The main cities along the river:

Main tributariesEdit

The main tributaries of the Río Negro are:


Related pagesEdit


  1. "GRDC - Le Río Negro - Station: Palmar". UNH / GRDC. Retrieved 7 August 2017.