This study focuses on the effects of urban wastewater on macroinvertebrate communities in the upper Ouémé basin in Benin. We found similar responses in African invertebrates to those observed in other parts of the world. However, we unexpectedly observed a stronger impact during the wet season than during the dry season. Furthermore, community resilience did not depend primarily on the distance downstream of the wastewater input, but rather on a combination of several factors.