Bacteria as solution to Kampala’s waste management

Anybody living in Kampala has experienced the ripple effects of not having a proper waste disposal management system in place. The problem is worse in major markets such as Kalerwe, Nakawa and Nakasero where traders dump Matoke peels and solid waste from leafy vegetables. But there is new research that promises to change waste management systems as we know it.
The 15-year-old research was carried out by scientists at Makerere University School of Agriculture and Environmental Sciences. Its focus is on how people can manage solid agricultural waste.
A team of eight scientists led by Prof Elly Sabiiti have been conducting this research on an incubation centre at Makerere University Agricultural Research Institute Kabanyoro (MUARIK) in Wakiso District to test different technologies which can be used to manage solid agricultural waste.

The project was funded by Swedish International Cooperation Agency and is worth more than $20m. Part of these funds were used on training eight PhD students, purchase biogas textures, refrigerators, digesters, computers and nutrient analysers.
While presenting the findings on technological advances in urban market crop waste utilisation, Prof Sabiiti explained that technology has advanced in the area of recycling.
Explaining the concept to Eastern Africa scientists dealing in waste management, Prof Sabiiti said they have discovered four types of bacteria which can be processed to dissolve solid waste into animal matter.
The types of the bacteria which exist in soil are Caulabacter bacteria species, Acquicella bacteria species, Bacillus bacteria species and Pseudomonas.
According to Prof Sabiiti, these bacteria species will be processed at the incubator in MAURIK and will be launched early next year.

How they work
He says it can be applied on solid waste where the organic composite of waste will be eaten by bacteria to make it soft and this can be used as animal feed.
The process will involve producing a culture using a media which contains, Potassium, Calcium and other oxides to provide food for the bacteria.

“Right now these bacterial are few in the soil and we want to multiply them in large quantities. The fact that we shall put them in the media which is food to them will make the multiplication process easy because they will be able to grow and multiply. We shall then process and sell to waste collectors who will be in position to degrade the waste solids into manure. It will help farmers because they will be solid at reduced price which farmers can apply as fertilizer in their farms. Secondly people will be sensitised to purchase the processes biodegradable powder which they can use to dissolve the solid waste in their homes and those collecting and managing solid waste such as KCCA and this will reduce on the waste dumping in the city making it a little clean,” he explained.
Dr John Baptist Tumuhairwe, one of the PhD students who worked in developing the bacteria usage technology explains that it is mechanism of shifting from organic processing of solid waste to inorganic mechanism.

“This is a biological process where we have identified microorganisms which we can inoculate for multiplication. What we do is get the bacteria from the soil, isolate them and mix it water after they are left to grow in a media. What is mixed in water will be sprinkled on waste material which will produce enzymes to dissolve the waste,” he explains.
“Nutrients will also be produced in the process which farmers can use as fertilizer. This technology is already being used in countries like Asia and we want to introduce it here. We shall process them both in liquid and powder for. Those in liquid form will be bottled and those in powder form packaged ready for sale. We have not yet started the process of packaging because we have to get certification from the Ministry of Agriculture and we are also looking for funding to support the process.”

Kampala waste crisis
According to the research, banana waste pollution in the city ranked high.
In Kalerwe market, 1,548 metric tonnes is produced every week and 3,000, 4,000 and 7,000 metric tonnes of Nitrogen, Potassium and Calcium respectively is lost to the atmosphere.
Further statistics indicated that 16kg of solid food waste is generated by every family living in Kampala every week. Kampala Capital City Authority (KCCA) takes between 20 to 50 per cent while and less than 10 per cent of the banana peel is sold as animal feed.
About 40 per cent of families living in Kampala and its surroundings burn their garbage which emits methane to the atmosphere causing greenhouse gases which leads to climate change. Some families bury the waste while more than half are dissatisfied with waste collectors.

The researchers recommend that farmers living in urban areas could use this solid waste to feed their livestock.
“There are a number of innovations to be applied by people, they can dry the banana peels or chop them into pieces and this can be given as animal protein to farmers practicing zero grazing. It cuts across for those practicing piggery, cattle and goat keeping. The waste from leafy vegetables is also another source of protein for animals. Traders dealing in selling these produce should take this into consideration because it can earn them extra income. Some people are already doing this but not all,” he noted.
Prof Sabiti says Kampala has a population of more than 1.5 million who generate 60,000 tonnes of solid waste. Of this, 40 per cent is collected and taken to official disposal sites such as Kiteezi landfills which are not managed well.

Coping mechanisms
Communities and families are advised to decompose solid waste which is a source of improving soil degradation.
This must be done carefully by selecting agricultural waste from plastics and other metals.
Prof Sabiiti explains that, at MUARIK they have been encouraging farmers to breed earth worms which are used as animal feed. Earth worms are also good ingredients for soil nutrient because the ones that die decompose and fix nitrogen in the soil. They are also useful for soil aeration because there are types of bacteria in soil which require oxygen.
Since people are depleting wetlands, the number of earthworms is reducing and breeding is the way to go.
There are also technologies where farmers can decompose banana peels and process it into liquid form and this can be used as fertilizer to improve on soil fertility.
Dr Constantine Katongole, who works closely with Prof Sabiiti on this project, says solid waste management is a big problem world over but the problem is dire in developing countries.

The bigger plan
National Environment Management Authority (Nema) executive director Dr Tom Okurut says since Nema is responsible for controlling pollution coming from waste, it is important to engage stakeholders who deal in waste management for knowledge sharing.
He explains that Nema is working with municipalities in waste management. So far, they have constructed municipal compositing sites in the districts of Mukono, Jinja, Mbale, Soroti, Lira, Arua, Masindi, Hoima, Kasese, Kabale and Mbarara.
Dr Okurut says most municipalities have 120 metric tonne capacity with exception of Arua and Kabale which have 70 metric tonne capacity.

“Municipal managers usually encourage solid waste to be brought on site using trucks which is sorted and decomposed to be used as manure by farmers,” he explains.
Sorting is done in about two days and water is added to it and it is mixed manually using tractors.
Nema is also working closely with cement factories where standards have been improved with a system which collects dust going into the atmosphere within the system which is recycled into cement.
Giving the statistics he said cement factories like Tororo and Hima cement are now producing 22,000 metric tons of bags of cement from dust annually. This started in Uganda but other neighbouring countries are adopting this technology.

Solid waste management policies

In Uganda, the responsibility of solid waste management lies with Local Governments as specified in the Public Health Act of 1964 a nd the Local Governments Act of 1997.
Although the Public Health Act of 1964 does not emphasise solid waste management (which was not a major problem then), the Act promoted good health through empowering health workers to prevent and minimise disease transmission resulting from unhygienic practices, and improper environmental management. However, the Local Governments Act of 1997 clearly mandates the city authority (Kampala City Council - KCC) the responsible for all the activities dealing with solid waste; from the point of production through collection to disposal.

The law mandates local governments with the overall responsibility of environmental management. The other law that directly provides for the management of solid waste in Uganda is The National Environment Statute (NES) of 1995.
It is this Statute that establishes the National Environment Management Authority (Nema) as the overall body, charged with the management of environmental issues. In general, the Authority in consultation with Lead Agencies is empowered to issue guidelines and prescribe measures and standards for the management and conservation of natural resources and the environment.
The Statute requires that the central government collaborates with the Local Governments in the management of local issues including among others, solid wastes.

[email protected]