Four years ago, Mr Dominic Wanjihia Kahumba visited the Nyalenda slums in Kisumu and came face to face with the deplorable, unhygienic conditions of pit latrines in the locale.
The appalling state of the pit latrines, which were emitting foul smell and making life in the slums unbearable, got Mr Kahumba thinking.
He took up the challenge of coming up with an innovation of a smart pit latrine that was environmentally friendly and affordable to users.
Apart from the poor hygiene brought about by pathogens from the shallow pit latrines, the foul smell made life unbearable and sickening for families struggling to eke out a living in the filthy slums.
Mr Kahumba decided to come up with a human waste management method that would not only suit the slum dwellers but also ideal to farmers by way of generating clean water for use in gardens and farms.
His efforts gave birth to 'Merry Loo', an improved latrine that is designed for use in areas with a high water table and rocky grounds.
Mr Kahumba says the pit latrine does not only do away with the foul smell but also produces clean and highly nutritious water, which can be used to water gardens and grow crops.
In 2017, he designed and constructed the first pit latrine in Nyalenda estate.
"Most people living in slums use pit latrines, which are very shallow and easily get flooded during rainy seasons," says Mr Kahumba.
He has been borrowing from the experience of a biogas expert to innovate on the smart pit latrine.
Mr Kahumba, aged 49, is a self-taught solid waste management expert and is the chief executive of the Biogas International Company, based on the shores of Lake Victoria in Kisumu. The pit larine project is one of his innovations.
He submitted samples of water generated from his solid waste management system connected to the pit latrine to Crop Nutrition Laboratory Services (Cropnuts), a leading East Africa agricultural testing laboratory and agronomy advisory services.
Cropnuts specialises in the analysis of soil fertility, water quality, food safety, pesticide residues, fertiliser quality, animal feeds, plant diseases and nematodes.
Mr Kahumba received a certificate from Cropnuts in 2017 giving a clean bill of health for the water product generated from the pit latrine for use in crop production. He has so far designed six such pit latrines and is currently working to cut down on the cost of the units.
Six of the pit latrines are in use in Nyalenda slums while seven others were sold to an orphanage in Nairobi.
The pit latrines have helped in making the environment safer in the slums by checking the flooding of ordinary pit latrines.
The innovation has helped in addressing unemployment among youths in the slums who are hired to help construct the toilets.
Mr Kahumba has hired 10 youths on the project and he is involved in training others on the innovation.
The pit latrine attracted his first client, Ms Mine Pabarza, a resident of Nanga, Nyalenda.
According to Ms Pabarza, Merry Loo came as her rescue plan after having been a victim of flooded toilets following the rising levels of Lake Victoria.
"A year ago, I was forced to build a new toilet after the lake level rose, leading to flooding of my shallow pit latrine," she said.
Just before she could start the construction of a new toilet, she came across the improved latrine.
He signed an agreement with the County Government of Kisumu in October 2020 for management of solid waste from Ahero market, which will be used in the production of fertiliser, biogas and interlocking bricks.
He hopes that the improved toilet will be embraced by more families living in slums and create a habitable and friendlier environment among communities in slums.