Manuel Mathis still remembers the human geography class that made such a lasting impression on him at secondary school. His teacher explained that millions of people go to bed hungry each night, in part due to the erosion and diminishing fertility of the soil they use to grow their crops. There and then, Mathis resolved to pursue a course of study that would help to alleviate hunger and poverty. In 2015, he enrolled at ETH and embarked on a degree programme in agricultural sciences. He was bombarded with huge amounts of theory about soil-plant systems, yet he yearned to spend more time digging in the soil to get hands-on experience. This led him to take a job, alongside his studies, at a composting plant in Fehraltdorf in October 2020. “The practical experience I gained there has served me well,” says the 25-year-old student on a Zoom call in late September. He is sitting in the living room of his apartment in the centre of Nairobi, looking rather under the weather. It turns out he is fighting off
another in a series of nasty stomach bugs. “It’s a natural consequence of working here,” he explains. “I get pretty close to all sorts of unfamiliar viruses and bacteria!”
A chaotic start
Since May, Mathis has been working at the composting plant run by the privately owned recycling company TakaTaka Solutions in Kenya’s capital Nairobi. Each day, he jumps in a white Nissan Estate and drives 20 minutes from his apartment to the 8,000-square-metre site on the city outskirts. When the idea first came up to do the internship for his Master’s degree at the plant, the plan was simply for Mathis to set up a small lab to help the workers monitor the pH, ammonium and nitrate content of the compost – all key indicators of high compost quality. But things worked out rather differently.“When I got here, everything was in total chaos,” says Mathis. “The whole plant was overflowing with fresh organic waste; the raw materials were just piling up everywhere rather than being turned into compost!” He then discovered that most of the workers had recently been dismissed for theft, and the plant’s long-time manager had gone on holiday, exhausted by the relentless workload. The only people left were two new, inexperienced workers and a tractor driver, who was reasonably familiar with the site, but who spent most of his time repairing the wheels of the only available tractor, which were constantly breaking down. “Everyone else gave the area a wide berth because of the terrible smell,” says Mathis.
After overcoming his initial shock, the student took stock of the situation. He quickly identified that the two key problems were profitability and infrastructure. The quality of the compost was so poor that its former buyers – most of whom were large agricultural suppliers – had turned their backs on the company after seeing the results of their own lab analyses. With no buyers for the decomposed compost, or humus, it was simply stacking up on site and the business was no longer making a profit. Mathis approached the company founder – a philosophy graduate with a German passport who had grown up in Nairobi – and persuaded him to order a new tractor from China as well as buying new wheels for the old one. Only then were they able to shift the towering piles of waste and line it up in long, 1.5-metre-high rows where the process of controlled decomposition could begin. The owner also agreed to invest in a new sifter to speed up the sieving process and relieve the bottleneck.
At the same time, Mathis quickly began recruiting workers. By November, he had a team of 20 people working at the plant. Their main job is to remove contaminants from the organic waste, such as old batteries, plastics and metal parts. Mathis knew from the start that everything relied on establishing a good working relationship with these untrained workers, each of whom was taking home a modest salary of 100 dollars a month. “Most of what I know about leading and motivating a team comes from my ten years of youth work in the church,” he says.
