The 8.7 kilometer-long National Canal (Canal Nacional), is the only untubed water body left in the central area of Mexico City. In 2019, the city’s Government allocated an initial amount of 2.6 million US dollars to rehabilitate the Canal Nacional. As the project progressed, an unexpected ded unexpected reaction took place: the emergence of citizen groups opposed to the rehabilitation works of the Canal Nacional. This text highlights the underlying nuances of social participation, as identified in this particular experience, where participation has been a way for civil society to influence government actions and politics oriented at recovering a socio-environmental space but also to hinder the rehabilitation project, thus affecting the right to a healthy environment of the population living in that space.