Nature-based Solutions for Wastewater Treatment in the Hilly Areas of Mwanza City of Tanzania

Abstract Submission: Nature-based solutions (NBS) present a viable strategy for tackling urban sustainability challenges, including ecosystem degradation, climate change vulnerability, and health issues stemming from poor environmental conditions. Sustainable Development Goal (SDG) 6 underscores the need for equitable sanitation, improved water quality, and the protection and restoration of water-related ecosystems. Globally, over 80% of wastewater is released untreated, posing significant public health and environmental risks. Approximately 2.4 billion people need improved sanitation, and 2.1 billion need adequate wastewater treatment facilities.
In Tanzania, achieving SDG 6's sanitation target by 2030 necessitates sustainable wastewater treatment solutions that support ecosystem preservation. In Mwanza City, only a tiny fraction of households are connected to centralised sewer systems. 90% of people rely on on-site sanitation systems like pit latrines and septic tanks. Poor sludge handling from these systems contributes to the spread of water-borne diseases. Furthermore, Mwanza's hilly terrain complicates conventional sanitation, leading to sewage overflows during heavy rains, contaminating streams and Lake Victoria, a water supply source to Tanzania, Kenya, and Uganda. The city's 12 creeks and rivers discharge rainwater and untreated wastewater directly into the lake. This study aims to design NBS for wastewater treatment in the Mwanza's hilly areas of Igogo, Isamilo, Mabatini, Mkuyuni, Nyegezi, Ibungilo, Kawekamo, Kirumba, Pasiansi and Kitangiri. The research explores technologies such as waste stabilisation ponds, constructed wetlands, decentralised systems, and anaerobic baffled reactors to mitigate pollution and protect Lake Victoria's health.

Learning Objectives/Expected Outcome (Optional) : To suggest source protection of Lake Victoria;
To design sustainable wastewater management