It flows northeast through Gitega Province past Murongwe to join the Ruvubu River.

[4] The surroundings of the lower Mubarazi are a mosaic of agricultural land and natural vegetation.

[11] In July 2016 Jean Bigirimana, an investigative journalist with Iwacu, was arrested by agents thought to be from the National Intelligence Agency and disappeared.

In August that year, two bodies in advanced decomposition were found in the Mubarazi River near the place where Bigirimana went missing.

[12] In December 2019 heavy rains caused the Mubarazi River to break its banks and flood roads and crops.