Innovative research specific hydrodynamic conditions Lake Kivu – Rwanda

Published: 28 November 2016

Lake Kivu, on the border between the Republic of Rwanda and the Democratic Republic of Congo in the tectonically and volcanically active East African rift valley system is 485 m deep with a surface area of 2400 km2 at an altitude of 1462 m. The lake is unique in the world due to its stable water column stratification that traps biogenic methane gas (CH4) and CO2 in the deepest layers (> 280m). The large amounts of CH4 (ca. 55 km3) are a source for sustainable green energy production. Rwanda plans to exploit the gas to generate electrical power. The pumped-up water will be washed, in order to extract the methane, before the water is re-injected in the Lake at other depths.

A partnership consisting of Deltares (Delft, The Netherlands), DeepBV (Amsterdam, The Netherlands), EPFL (Lausanne, Switzerland) and EAWAG (Kastanienbaum, Switzerland) has been awarded a contract for the study of deep currents, water levels and waves in Lake Kivu. The project has been granted by the Energy Development Corporation Ltd (EDCL) of Rwanda and will be supervised by the Lake Kivu Monitoring Program (LKMP).

maplakekivu

The objective of this assignment is to carry out an innovative research into the specific hydrodynamic conditions of Lake Kivu. This involves setting up and executing a measurement program in the lake and modelling of the deep lake hydrodynamics.

A measurement campaign will be set up to allow detailed measurements of the deep currents across the whole vertical profile in Lake Kivu. The study of deep currents will lead to a better understanding of the effects of deep water extractions and re-injection upon the lake structure (e.g. stratification) in the deep layers (around 240 m) and in the biozone (around 0-70 m). In addition, measurements of lake levels and waves heights are required for the safe design of the platform and security of boats on the lake. The system will be jointly tested and used by local scientists to develop the expertise necessary for further exploitation of the lake including extraction of methane gas and hydro-power on River Rusizi, and for other uses of the lake such as transport, ports, fishing and tourism. Specifically, the results of the measurement campaign will be used to improve and calibrate models of the three-dimensional hydrodynamics of the lake. During the assignment, work will be carried out in close collaboration with local and regional scientists associated with the project so that they become knowledgeable and self-reliant.

The project will run from November 2016 until April 2019. At the end of the assignment, the local scientists should be self-reliant in the use of the system, and in analysing and interpreting its data. The system will contribute to the provision of information needed to allow policy making for an integrated water resource management of Lake Kivu.