Food Loss and Waste

By: Green Knowledge Foundation

Every morning in Nigeria’s Benin City, before traffic builds up and markets awaken, faint plumes of smoke rise from heaps of waste scattered across open spaces. In Jos, plastic bags cling to drainage channels after heavy rains. On the outskirts of Abuja, government-approved dumpsites quietly ferment under the sun. In Lagos, Africa’s most populous city, towering landfills on the city’s fringes swell daily as trucks unload tons of mixed waste, while clogged canals and lagoons trap floating debris beneath the humid coastal air.

What appears to be ordinary waste is, in reality, an invisible climate threat: Methane.

Across Nigeria’s rapidly growing cities, unmanaged organic waste is releasing one of the most potent greenhouse gases into the atmosphere. The Multi-Solving Action to Methane Reduction in Nigeria (MAMRN) Project was conceived in response to this urgent environmental challenge.

When organic waste, food scraps, green waste, and agricultural residues decompose in oxygen-deprived conditions, such as open dumpsites, they produce methane (CH₄). Methane is not just another greenhouse gas. It is over 80 times more potent than carbon dioxide in the short term, responsible for nearly half of the global warming already experienced, and the second-most-important anthropogenic greenhouse gas after Carbon dioxide (CO₂).

Municipal solid waste landfills globally account for approximately 11% of anthropogenic methane emissions. For every tonne of waste sent to landfill, an estimated 50–100 kg of methane may be released; equivalent to roughly 1,610 kg of Carbon dioxide (CO₂) per tonne due to methane’s high global warming potential.

Nigeria generates over 32 million tons of municipal solid waste annually, yet only about 20–30% is formally collected. More than 90% of waste in many developing regions ends up in open dumpsites, waterways, unused land, or is openly burned. 

Nigeria’s waste composition is particularly significant: approximately 50–60% of municipal solid waste is organic. This means that a large proportion of waste entering dumpsites is actively generating methane. In 2021, methane accounted for 44.6% of Nigeria’s total greenhouse gas emissions, making it one of the country’s most critical climate pollutants.

With Nigeria’s population estimated at over 223 million and projected to rise significantly by 2050, urban centres such as Benin City, Jos, Lagos, and the Federal Capital Territory (FCT) are expanding rapidly. Urbanisation, rising consumption patterns, and limited infrastructure have widened the gap between waste generation and effective management.

Globally, about 2.01 billion metric tonnes of municipal solid waste are produced annually, and this is expected to increase by 70% by 2050. Sub-Saharan Africa alone is projected to reach 269 million tonnes of waste per year by 2030. Nigeria mirrors this trajectory.

Nigeria is already experiencing the effects of climate change, including increased flooding and stormwater runoff, coastal erosion and sea-level rise, rising temperatures and heat waves, agricultural productivity losses, food insecurity and water scarcity, and increased disease outbreaks. Open dumpsites worsen these impacts. During heavy rainfall, flooding dislodges waste, spreading pollutants into homes, schools, and water bodies. Methane buildup within dumpsites also presents explosion hazards.

Rather than treating waste as a burden, the MAMRN project reimagines it as a resource. Material Recovery Facilities (MRFs) are being established to divert organic waste from dumpsites, process it into compost, sort recyclables such as plastics, glass, paper, and e-waste, integrate and strengthen the role of waste pickers, and reduce methane emissions at the source. Each facility is initially designed to manage approximately 260 tons of waste annually.

By converting organic waste into compost, the project improves soil health, reduces dependence on petroleum-based fertilisers, supports climate-smart agriculture, and minimises methane emissions from decomposition. Farmers are trained through the My Zero Waste Farm Project, with at least 20 farmers per state serving as trainers to expand adoption across communities. Organic waste is also processed through Black Soldier Fly (BSF) farming to produce high-protein animal feed, organic fertiliser, and new livelihood opportunities. This model strengthens local food systems while reducing methane emissions from landfills.

Methane reduction through improved waste management delivers multiple benefits, including lower greenhouse gas emissions, reduced flooding and pollution, improved public health outcomes, job creation for waste pickers and farmers, strengthened urban food systems, and contributions to SDGs 1, 2, 6, 7, and 13. The project aligns with Nigeria’s long-term low-emission development strategy, aiming to reduce emissions by 50% by 2050 and to transition to a circular economy.

Methane may be invisible, but its impacts are not. The rising temperatures, flooded streets, polluted waterways, and strained agricultural systems across Nigeria tell a visible story of climate vulnerability. The MAMRN Project represents a shift from open dumping to resource recovery, from unmanaged emissions to data-driven reductions, and from environmental degradation to circular-economy solutions.

By diverting organic waste, empowering communities, integrating informal waste workers, and influencing policy, Nigeria takes a practical step toward reducing methane emissions and building climate resilience. The future of Nigerian cities depends not only on how much waste is produced, but on how wisely it is managed. 

The path forward requires action from everyone.  Policymakers can strengthen regulatory frameworks that recognise waste pickers as formal climate workers and prioritise waste-sector investments in national climate plans. Development partners and funders can direct climate finance toward community-led Material Recovery Facilities and methane monitoring infrastructure. 

Businesses can adopt circular procurement practices, reducing organic waste across supply chains and supporting compost markets. Farmers can integrate compost and Black Soldier Fly products into their practices, improving soil health while cutting dependence on chemical fertilisers. And as a reader, you can start where you are: composting at home, supporting local waste initiatives, or simply sharing this blog post to grow awareness. 

In that transformation lies the power to slow global warming, protect communities, and build a cleaner, more sustainable future.

This article is the second in a series on the Methane Reduction in Nigeria (MAMRN) Project, implemented in collaboration with CfEW Jos, SraDev Lagos, Pave Lagos, CODAF Epe Lagos, and SEDI Benin City.