Under an overcast sky on a chilly November morning, a group of people from Waterkeeper Alliance, wearing green waterproof overalls, gloves and gumboots, joined Komb Green Solution, a community-based organisation from Korogocho slum to clean a two-kilometre stretch of Nairobi River.
The river flows from its source in the Ngong Hills, 35 kilometres southwest of Nairobi, through the city, and some 500 kilometres east to the Indian Ocean at Kenya’s Coast.