The total surface area of the Muvumba catchment within Rwanda is 1,568 km², which represents 5.95 % of the total surface area of Rwanda (26,338 km² including water bodies). The Muvumba River is transboundary with Uganda, which registers an additional hydrological catchment area of 2,146 km² for a total hydrological catchment area of 3,714 km².
The Muvumba Catchment finds its source in Rwanda on the Mulindi River, located in the mountainous and high-rainfall central northern part of the country at an altitude of 2,030 m. The Mulindi River flows north over a length of 22.5 km to Uganda on to a flat wetland zone near Kabale, from where a complex flow pattern originates that ultimately joins the Muvumba River before it eventually flows back into Rwanda at an altitude of 1,460 m above sea level. The length of the Muvumba river within Rwanda is approximately 56.3 km. Just south of Nyagatare, the Ngoma River with a number of tributaries contribute their flow to the Muvumba River which flows in a north easterly direction to follow the border between Rwanda and Uganda before finally joining the Akagera River in the northeast, where the borders of Uganda, Rwanda and Tanzania meet. The final altitude of the Muvumba River is about 1,280 m.
Irrigated and agricultural wetlands occupy a significant part of the catchment in the central and northeastern parts. In the southern part of the catchment, there are numerous forest plantation. Natural open land is located in the central parts along the border with Uganda and in the northeast. Built-up areas are mostly dispersed, with some concentration around Nyagatare and Gicumbi urban areas.