Understanding River Discharge

Understanding river discharge is essential to estimating landscape responses to rainfall and other climatic driving forces, planning infrastructure, predicting floods and droughts, and assessing ecosystem conditions. Discharge measurements in Africa are scarce. Yet, there are several highly affordable and locally viable innovative techniques to measure discharge. On Friday 1 November, as part of the annual SADC_WaterNet symposium, Micha Werner, Mark Graham, Leisa Mokuoane, Dr. Hubert Samboko, Nicholas B. Pattinson, PhD, Camila Justine Jacinta Haux and Hessel Winsemius organized a fieldwork experience to demonstrate these methods. This was a collaborative effort between Rainbow Sensing, GroundTruth, OpenDroneMap, University of Zambia, Lesotho Department of Water Affairs, UNICEF and IHE Delft Institute for Water Education. The event was supported by the EU HORIZON project TEMBO Africa, UNICEF, and GroundTruth in partnership with the International Water Management Institute (IWMI) within the CGIAR Initiative on Digital Innovation.

Modular Flood Early Warning System an Approach to Flood Adaptation

One major impact of climate change is the ever-increasing frequency of foods events as a result of deep convective storms exacerbated by the increase in global surface temperature. Therefore, flood early warning system (FEWS) is critical tool in safeguarding life and protection of property of the vulnerable communities.

FEWS are used whenever there is a need to understand the potential impacts of flooding and to make informed decisions about flood risks and management and mitigation flood modelling can be used for purposes such as planning and design of sustainable drainage and storm water management systems or designing and planning flood protection systems or identifying areas at risk of flood and developing evacuation plans, assessing the impact of land use changes, identifying areas that are vulnerable to flood and prioritizing for flood mitigation.

Flow measurements at the Lunsemfwa Hydropower station with the DischargeKeeper and DKlight

One lego component of the TEMBO project is to develop transformative camera-based river discharge measurements that are non-contact, cost effective, easily maintained, deployed, and adapted to local context in Africa. To this endSEBA DischargeKeeper (TRL 9)observation systems will be installed, side-by-side with other observation systems, for benchmarking purposes. Two pilot sites will be installed, one in theLunsemfwabasin in Zambia, and the other one in the Black Volta in Ghana

The firstDischargeKeeper (DK)has already been installed at the diversion dam inLunsemfwa. The DK is solar-powered, has a bullet camera and it is using an external radar to measure the water level. The DK has a cellular router, but we are also testing satellite communication via the Starlink system.

VLOG ON RIVER MONITORING

One of our approaches for river monitoring in the TEMBO project includes image velocimetry using OpenRiverCam for river velocity estimation, dry bed bathymetry using photogrammetry in OpenDroneMap, and wet bed bathymetry using sonar via a fish finder. Work to date has piloted this approach at three locations in Ghana within the Black Volta Basin. Some visualization of this work is available in this preliminary video introducing the work.

Flood Early Warning System (FEWS) for Narok County in Kenya; A Key Decision Tool for Farmers and Disaster Managers

Frequent flooding is one of the consequences of the changing climate that is affecting most communities in Sub-Sahara Africa. When it rains it pours, and Narok County in the Southern parts of the Great Rift Valley in Kenya is a good example. Situated within the Valley of the Great Rift Valley Narok Town and Masai Mara National Reserve are hot spots for flooding during the rainy seasons in Kenya. The intense rains leave no time for the water to infiltrate leading to flooding. Passing through the Narok Town and Masai Mara National Reserve is the Enkare Narok River which floods due to heavy rainfall uphill in the Mau Forest the largest water tower in the Country.

In order to safeguard life and properties of the community, informed decision making based on accurate rainfall forecast is a key ingredient. Numerical weather prediction (NWP) models plays a key role in flood forecasting. Using the WRF model, KMD has established a limited area model with the outer nest extending into Central Africa to take care of the unstable Congo air mass and into the Indian Ocean to cater for the ocean dynamics running at 10 km resolution.  The inner domain running at 2 km resolution extends from the Lake Victoria basin through the Rift Valley and the Highlands east of Rift valley. Shown in figure 1.

The Transformative Role of TAHMO in Empowering TEMBO Africa

In an era of rapid climate change and its far-reaching impacts, the need for accurate weather and climate data has become increasingly vital for communities, policymakers, and researchers alike. In Africa, where vulnerable populations are disproportionately affected by climate-related disasters, having access to reliable weather information can make a significant difference in the lives of millions. This is where the Trans-African Hydro-Meteorological Observatory (TAHMO) steps in, playing a transformative role in empowering TEMBO Africa.

The Importance of Weather Data

Accurate and timely weather data serves as a foundation for various sectors, including agriculture, disaster management, water resources management, and infrastructure development. In Africa, where a significant portion of the population relies on rainfed agriculture, access to weather information becomes even more critical. Farmers need precise forecasts to make informed decisions about planting, irrigation, and crop protection. By utilizing weather data, governments and organizations can enhance early warning systems, mitigate the impact of climate-related disasters, and improve overall resilience.