New Measurements of Water Dynamics and Sediment Transport along the
Middle Reach of the Congo River and the Kasai Tributary
Abstract
The Congo River provides potential for socio-economic growth at the
regional scale, but with limited information on the river dynamics it is
difficult for basin countries to benefit from this potential, and to
invest in the development of water resources. In recent years, the
number of hazards related to navigation and flooding has sharply
increased, resulting in high loss of human lives as well as economic
losses. Associated problems of river management in the Congo also
include inefficiency in hydropower production, an increase in rate of
river sedimentation and land use changes. Accurate information is needed
to support adequate management strategies such as prediction of
navigation water levels and sediment movement, and assessment of
environmental impacts and engineering implications of water resources
infrastructure. Modelling approaches and space observations have been
used to understand the Congo River dynamics, but their effective
application has proved difficult due to a lack of ground-based
observational data for validation. Recent developments in data capture
with acoustic Doppler technologies have considerably improved
measurements of river dynamics. As well measuring river discharge, they
also allow the analysis of the multiple hydrodynamic features occurring
in fluvial systems. This paper presents the results of field measurement
campaigns carried out in the middle reach of the Congo River and the
Kasai tributary using state of the art measurement technology (ADCP,
Sonar, GNSS) for investigation of large rivers. The measurements relate
to river flow at multiple transects, river bathymetry, static and
continuous water surface elevation, and targeted sediment sampling along
the river. The paper provides a descriptive summary of the measurement
results, a discussion on the application and performance of the
equipment used in the Congo River, and lessons for future use of this
equipment for measurements of large rivers in a data scarce environment
such as the Congo Basin.