Guests of the Alexander von Humboldt Foundation at TU Darmstadt

My field of research is fascinating. The best way to explain it to non-specialists is…

Water is one of the most important natural resources without which there would be no life on earth. The water resources available for use both in agriculture and in our cities is limited by nature. Although there seems to be plenty of water on earth, it is not always in the right place, at the right time and of the right quality. Adding to the problem is the increasing evidence that chemical wastes improperly discarded yesterday are showing up in our water supplies today. My research aims at understanding the complex water systems of the Earth and help solve water problems.

What research questions are you currently working on?

The study aims at modelling both point and non-point source pollution in the Sosiani River Catchment draining into Lake Victoria, the world’s second largest freshwater lake. The Soil and Water Assessment Tool (SWAT) is a GIS-linked catchment scale model capable of simulating hydrology and water quality for 100 or more years. The research will incorporate the in-stream kinetics of an in-stream water quality model, QUAL2K, into SWAT, thus improving the overall capability of the SWAT model. The combined model will be applied to the Sosiani River Catchment, within Eldoret City, in Kenya.

My most important success in research to date is…

… applying catchment models that include sufficient process details to allow for the implementation of controls such as wetlands, dams and buffer strips. The major contribution being to link hydrology and Non-Point Pollution (NPS) processes by describing and defining pathways through which pollutants move in rural and urban catchments. This involve studying the dynamics and connectivity of water, sediments and nutrient fluxes by combining hydrometric, hydro-pedological geophysics and stable water isotope techniques to model and interpret the field and laboratory data.

Will the results of your research have a concrete impact on our everyday lives now or at some later date?

The established database of the major types of surface water pollutants and their sources in Kenyan Rivers will be used to predict the behaviour of the riverine systems under the various pollution loadings in future. The self-purification processes of rivers and the role of wetlands in improving water quality will be shown. The knowledge gained will be disseminated to benefit institutions and organizations charged with enforcing the river effluent standards in Kenya which include local authorities, government departments, universities and other relevant research organizations.

What innovative developments are you expecting in your field of research in the next few years?

A key objective of the research is to protect and enhance the status of aquatic ecosystems in rural and urban settlements in Kenya. Management of such systems must be carried out at the catchment scale which requires catchment scale modelling of surface water-groundwater interactions, contaminant transport and ecological impacts. My focus would be to understand and model these interactions and ecological impacts using mathematical models and to apply these models to real case studies with an aim of having improved water quality.

I became a researcher because …

… rivers in Kenya experience high pollution levels from municipal and industrial point sources besides that from non-point sources resulting from agriculture, erosion and other commercial activities. Rivers have thus progressively shown signs of water quality deterioration and there is need to find ways of reversing this trend. Agricultural pollution mostly occurs over a wide area, and its sources are diffuse and difficult to identify. It also varies unpredictably over time and space, and depends not only on rainfall patterns, but also on the land slope and soil characteristics.

I have chosen TU Darmstadt because …

… when I applied for Humboldt Fellowship for Experienced Researchers as a visiting researcher, one condition that I had to fulfil was to work with a German Professor. Prof Britta Schmalz’s research area of interest converged with mine. I am forever grateful to Britta for her patience and having accepted to host me in her team. Because of the corona situation in the world, we kept postponing the time to start my research stay in Germany. It has now come to pass and gaining valuable research experience from the Technical University of Darmstadt in now a reality.

What reputation does German research enjoy in your home country?

German universities have a reputation of top-notch research that is well supported by modern research facilities. Additionally, many Nobel prize winning Professors have been locally trained within these German institutions of higher learning. It is a great privilege to many of us who have been lucky to be associated with these institutions. Germany is also known to be a welcoming nation to visitors.

What lasting impressions will you take back home with you from your time in Darmstadt and Germany?

My future aspiration is to apply the knowledge gained in TU Darmstadt to assist my country in mitigating water pollution issues currently experienced in our urban and rural catchments. I am also looking forward to visiting many places in Germany with an intention to share with my people back home the good memories in the 18 months I shall be in the country.