An investigation carried out by Reject, revealed that food crops, especially root-crops and vegetables are being grown in residential areas with the farmers using sewer water. The crops might look healthier and fresh but they have long term negative health hazards to those who use it.
Indeed, a good number of the city’s residents ignorantly feed on these food crops grown in the sewers despite experts warning that they could have adverse effects on them.
Nairobi Dam is one of the areas where the urban farmers have encroached to grow various roots crops and other vegetables using sewer water. The dam used to be a water reservoir for domestic and emergency water supply for the then city’s rapid growing population in the early 1970s.
The dam was also used as a centre for recreational activities such as sport fishing and sailing as well as a picnic site.
However, this is no longer the case today. The dam has become a centre for collection of domestic, industrial and solid discharges dumped into the reservoir since early 1990s.
A visit to the dam reveals that yams are common crops and occupy tens of acres on the dam land. Other crops include bananas, sukuma wiki (kales), cabbage, sugar cane, Napier grass, tomatoes and onions.
These crops find ready market and are consumed in the neighbourhood, starting with residents of the sprawling Kibera slum itself, Woodley, Highrise, Jamhuri, Lang’ata, Otiende, Kenyatta market and other areas in the city.
According to an expert, the dam could contain heavy toxic metals such as lead, zinc, iron, copper, cadmium, chromium and aluminium due to accumulation of household and industrial waste in the dam.
These heavy metals contaminate the soil, as a result, food crops grown in the dam use it for its photosynthesis and transpiration activities.
A water engineer Vivian Nabuso says one of the ways heavy metals enter our bodies is through the food we eat. She cautions that most people who feed on these foods could suffer from organ failure, cancer, eye problems and other reproductive health problems.
“Concentration of heavy metal toxins have the ability to impair cells, tissues and body systems responsible for our behaviour, mental health, and proper physiological functioning,” Nabuso cautions.
She explains that though these metals are essential to human life, high intake is harmful. For example high intake of copper causes anaemia, liver and kidney damage. High intake of mercury causes damage to the brain and the central nervous system while chromium long term exposure can cause kidney and liver damage, and to circulatory and nerve tissues as well.
Despite the health concerns, farming activities continue unabated in Nairobi dam. James Ouma owns two acres of land under yams. He has farmed and sold yams for the last five years.
“I began this farming like a joke after seeing other people planting crops here at the dam without anybody questioning them. It took me time before taking a bold step to look for an empty space where I planted the yams,” Ouma reveals.
Ouma prefers yams because they fetch more money when harvested and sold to the residents. He says: “This land is swampy and fertile. Yams mature between six to eight months.”
Most of his customers are traders from the slums who purchase yams in large quantities at wholesale price before selling them at retail cost. Others have subdivided their land into several portions and have planted crops such as sukuma wiki (kales), carrots, cabbage, sugarcane and yams.
A trader from Kibera, who sought anonymity says food crops at the dam are cheaper because the land is free. “These farmers got this land free of charge. Their prices must be fair especially for some of us buying in large quantities,” she discloses.
From the dam these traders sell these crops to other slum dwellers at higher prices. Some rake in more than 100 per cent profit. In fact some have bought themselves motorbikes, pick-up cars and even built permanent houses in their rural homes.
A female farmer popularly known as Nyaboke has farmed on the dam for five years now and cultivates vegetables among them kales and tomatoes. Prior to this farming, Nyaboke owned a grocery kiosk that did not pay her well.
“I was introduced by a neighbour who had started farming at the dam earlier,” she recalls.
Today Nyaboke owns half an acre of land under which she has vegetables. She explains: “I supply vegetables to other small scale traders within the slum, four days a week. I also hawk it personally because it pays more than giving to small scale traders.” Nyaboke makes at least KSh5,000 per week.
Benjamin Njoroge who plants yams and Napier grass is one of the oldest farmers at the dam. Njoroge started by raising vegetables on the sides of the dam after the 1998 El nino rains. “El nino rains left the better part of the dam silted. It looked fertile and attracted farming activities,” Njoroge recalls.
In 2000, Njoroge discovered a number of people had already taken portions of land and planted vegetables. Encouraged by these farming activities, he abandoned vegetable growing and embarked on larger scale yam and Napier grass growing.
The dam might have lost its initial glory but remains a source of income for several people especially at Kibera slums. Farmers say, they saw fertile land lying idle and resolved to make wise use of it. “And our efforts are still paying off,” they brag.
Those doing farming on the dam mistakenly believe that the wastes make good fertilizer for their crops. The number of farmers at the dam is currently unknown. However, there are boundaries and each one of them knows each one’s plot. They also know the sizes of their pieces of land which ranges from small portions to over two acres hence no quarrel arises.
These farmers are not sure when they will abandon farming activities on the dam. However, they are aware of the Government’s previous effort to rehabilitate the dam. They emphasize that only rehabilitation of the dam can halt their farming. The Government’s failure or delay to rehabilitate the dam being a bonus for them.
This story was originally published in the Reject Online Issue 83