The Water and Sanitation Corporation (WASAC) has launched a tender process to recruit a firm to conduct a feasibility study for the Kigali Climate Smart Wastewater Management Project, a major initiative aimed at establishing a dedicated sewage system for Gasabo District. Kigali generates approximately 3,240 cubic metres of wastewater per day, with about half discharged untreated into the environment, according to a 2022 study published in the International Journal of Scientific and Research Publications by researchers Jean Pierre Bavumiragira, Edwin Kipkrui, Yves Ndizeye, Pascaline Uyisaba, and Alex Bazambanza. ALSO READ: Construction of Kigali sewage system begins in June WASAC spokesperson Robert Bimenyimana said the Gasabo project is separate from the ongoing sewerage development in Nyarugenge District, which includes a treatment plant in Giticyinyoni. “While both projects serve the same purpose, the difference lies in the coverage area,” he said. Funding for project preparation has already been secured, while financing for implementation will be mobilised after the completion of designs and feasibility studies. The selected firm will also carry out a preliminary financial viability assessment of the proposed infrastructure. In parallel, WASAC has advertised a consultancy position for a Wastewater Management Support Expert to support project preparation. The role, funded by the Asian Infrastructure Investment Bank (AIIB) through its Project Preparation Special Fund, is open until April 6, 2026. ALSO READ: Lack of central sewerage system a time bomb The project includes comprehensive feasibility studies, environmental and social impact assessments (ESIA), and detailed engineering designs. The selected expert will provide technical oversight, ensure quality assurance, and support coordination throughout the preparation phase, while also contributing to capacity building within WASAC. Protecting key waterways According to tender documents, the project aims to reduce pollution in major rivers, including Nyabugogo, Nyabarongo, and Akagera, which ultimately drain into Lake Victoria. The Nyabugogo river flows through Kigali into the Nyabarongo, which then joins the Akagera River along Rwanda’s eastern border before emptying into Lake Victoria. Reducing pollution in these waterways is critical given their ecological and economic importance. Why Gasabo? Wastewater generation in Gasabo is rising rapidly due to urban population growth. Most households rely on pit latrines and septic tanks, systems that are increasingly inadequate in densely populated areas. ALSO READ: Why Kigali’s central sewerage system delayed “WASAC has prioritised the preparation and implementation of the Kigali Climate Smart Wastewater Management Project for Gasabo District,” the tender document states, noting that the Government of Rwanda has sought support from AIIB for project preparation and financing. Key project components The project is structured around three main components: Wastewater conveyance system This involves designing and constructing a climate-resilient sewer network, including household connections and integration with existing semi-centralised systems. Designs will prioritise gravity-driven flow to minimise reliance on pumping stations, while incorporating nature-based solutions such as wetland restoration. ALSO READ: Construction of Kigali waste treatment plant at 70% Treatment and reuse A wastewater treatment plant will be constructed, alongside systems for safe septage management. Treated wastewater will be reused for non-potable purposes such as irrigation, industrial processes, landscaping, and groundwater recharge, reducing pressure on freshwater resources. Project management and capacity building This component focuses on strengthening institutional capacity within WASAC and other agencies through training, equipment procurement, software licensing, construction supervision, and monitoring and evaluation. Scope and technical work The project will cover key sectors in Gasabo, including Kinyinya, Kimironko, Remera, Gisozi, Bumbogo, Jabana, and Nduba, while also assessing nearby areas such as Jali and Gatsata. ALSO READ: City of Kigali to set up fecal sludge treatment plant in Masaka Consultants will assess existing sewerage infrastructure—including pipes, drains, treatment facilities, and household connections—to determine their condition and suitability up to 2058. Based on this, a rehabilitation and integration plan will be developed. Key planning factors include population growth, water consumption patterns, distribution of households and businesses, septic tank capacity, accessibility, and residents’ willingness to desludge. The study will also evaluate whether combined or separate wastewater and stormwater systems are most appropriate. Treatment technologies Various treatment technologies will be assessed, including options that incorporate renewable energy and agricultural reuse. Nature-based solutions and integration with wetlands will be prioritised. Treated wastewater could be reused for flushing, road washing, irrigation, industrial use, and wetland restoration, supporting a circular approach to water management. Expert insight Environmental health expert Abias Maniragaba said a single, centralised sewage system for Kigali is impractical due to the city’s terrain. “A central system would require costly pumping because of slopes ranging from 45% to 50%. Kigali has about five catchments, so decentralised systems that rely on gravity are more viable,” he said. He added that separate systems for districts such as Gasabo, Nyarugenge, and Kicukiro are more practical, and that identifying catchment areas is key to determining optimal infrastructure placement. Maniragaba also warned that existing septic and underground tanks pose environmental and safety risks, including potential landslides, underscoring the need for proper environmental impact assessments. Rwanda aims to achieve 100% sanitation service coverage by 2030, in line with the Sustainable Development Goals.
