Across the districts of Karongi, Muhanga, Nyamagabe, Huye, Nyaruguru, Gisagara, Nyagatare, Kirehe, Ngoma, and Bugesera, communities are increasingly affected by environmental degradation linked to poor road drainage systems, an assessment by Transparency International Rwanda (TI-Rwanda) has found.
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Despite existing Environmental Impact Assessment (EIA) requirements, the report showed that some road projects present design flaws, insufficient hydrological analysis, and weak construction supervision, leading to recurring drainage failures.
Abias Maniragaba, Senior Project Coordinator at TI-Rwanda, said the challenges reflect a broader structural problem in road design, maintenance, and compliance across Rwanda.
The absence of effective drainage infrastructure on multiple road segments has created serious environmental, social, and safety hazards in the communities.
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Key social, economic, and environmental effects experienced include blocked, undersized, or misaligned culverts, stagnant water accumulating in roadside depressions, overflow of runoff into wetlands, farmlands, and community properties, and high-velocity water flow that can sweep individuals or livestock.
They also include rapid embankment erosion due to poor compaction and weak soil protection, and road structure destabilisation, requiring costly repairs.
Road-related erosion
On Karongi-Muhanga road, the absence of side drains and culverts accelerates gully formation, while in Gasaka sector, Nyamagabe district, runoff flows directly along roads, stripping topsoil and damaging road surfaces, according to the report.
Along Huye-Ndago Road, high-velocity water cuts into farmland, reducing crop yields and generating sediment loads downstream.
The situation is critical in Kibeho sector, Mubuga Cell, Mubuga Village, where uncontrolled water runoff is destroying farms, washing away fertile soil, and threatening crops and household properties.
In Cyeru sector, Burera district (Butaro road), the road construction exhibits poor environmental practices, disregarding the area’s topography and natural water flow, which causes erosion, soil degradation, and farmland destruction.
Recommendations
Experts who compiled the report proposed some engineering solutions, including redesigning and upgrading culverts based on updated hydrological data, installing stormwater management systems such as check dams, channels, riprap, gabions, stabilising embankments using proper compaction and vegetation cover, and developing drainage master plans for all new road projects.
Strengthening institutional arrangements has also been recommended.
They include mandating independent environmental audits during and after construction, establishing joint inspection teams (RTDA, district engineers, and REMA), introducing contractor accountability frameworks with penalties for poor performance, and integrating road drainage maintenance into district annual action plans.
The study said there is a need to strengthen compliance with national road construction guidelines to respect and include climate and disaster risk safeguards.
"It is important to call upon concerned public institutions to ensure that all major roads follow road drainage guidelines and other natural preservation principles to avoid altering hydrology. Enhance ESIA compliance monitoring, including digital reporting tools.”
RTDA embarks on drainage rehabilitation
Rwanda Transport Development Agency (RTDA) has initiated a countrywide mapping of road drainage issues.
As part of this effort, pilot works on selected priority sites have already begun to be corrected, including those along the Muhanga-Ngororero-Mukamira and Gisiza-Pfunda roads.
The interventions involve installing stronger foundations with layered stone structures, water-resistant materials, and wider concrete-reinforced drainage channels to ensure long-lasting resilience against climate-related shocks.
Gemma Maniraruta, Director General of Water and Sanitation at the Ministry of Infrastructure, noted that incorporating proper road drainage from the earliest design stage is already producing visible benefits.
"Effective drainage is essential to protect receiving waters and wetlands,” she said, adding that "the restoration and development of wetlands as part of enhanced stormwater management across the country.”
She recommended that TI-Rwanda submit its report, findings on drainage issues, and recommendations to the Ministry of Infrastructure so that the next phase of implementation can be ensured.