[Download a newly launched report—Greening Africa’s Cities—to learn more about the interplay between urbanization and sustainability in Africa.]
Take Kampala, Uganda as an example. It is estimated that only 5% of the city’s population is connected to the sewer network, with 95% of the population having access to basic on-site, mostly shared, sanitation. As a result, the volumes of flows entering the city’s Nakivubo wetland channels have increased significantly with contaminated runoff from informal areas and partially treated wastewater from the overburdened sewage works. This has significant negative impacts on human health, wetland and lake ecological function, as well as the cost of water supply to the city from Lake Victoria’s Inner Murchison Bay.
The city is considering rehabilitating the Nakivubo wetland, but it would cost US$53 million upfront, in addition to ongoing maintenance and operating costs of about US$3.6 million per year. Although benefits would include water treatment cost savings of US$1 million and recreational benefits exceeding US$22 million per year, it is now too costly and impractical to restore the wetland to a state where benefits can be achieved.