Akagera River Discharge Monitoring and Hydrology
The RRFHP is constructing the 80MW dam on the Akagera River just upstream the Rusumo Falls using a Run-of-River (RoR) scheme – on behalf of RPCL. The water intake is on the right bank (Tanzanian side) at about 100 meters upstream the dam axis, delivering water through a 680 meters long headrace tunnel to the 80 MW Power Plant with 3 Kaplan turbines located about 500 meters downstream the Rusumo Falls.
The dam construction using Akagera River waters downstream of the confluence between the Ruvubu River from Tanzania-Burundi and Akagera River from Rwanda. The catchments of the two rivers include most of Rwanda for the Akagera River and significant parts of Burundi and Ngara District of Tanzania for the Ruvubu River. In Rwanda, Nyabarongo River upstream of Rweru Lake becomes the Akagera River downstream of the lake. The Nyabarongo and Akagera Rivers are directly connected.
However, in 2016, a river avulsion occurred, and the Nyabarongo River now flows into Rweru Lake and is no longer directly connected to the Akagera River. However, an inlet to the Akagera River eastwards from the location where the avulsion occurred still allows reduced amounts of water to flow into the Akagera River from the Lake Rweru when the water surface elevation in the Lake is high enough. The effects of this avulsion on Lake Rweru and Akagera River discharge is still under analysis.
The Akagera River Discharge Monitoring is a suitable tool established to detect and monitor changes resulting from the Plant operations and natural environmental changes. The water discharge from Akagera River going downstream plays an important role in guiding driving the climate system, as the freshwater inflow into the oceans may influence oceanic circulation patterns.
RPCL is endeavoring to monitor all changes in flow regime in the Akagera River that may impact the planned electricity generation from RPCL Power Plant. RPCL is currently undertaking necessary assessments to predict impacts of the Nyabarongo River avulsion, and, if required and necessary, develop cost-effective mitigation measures to ensure planned power production is well done.
Water Flow at Rusumo Falls