Who is polluting River Nyabarongo?

A view of Nyabarongo river that  is the longest river in Rwanda, part of the upper headwaters of the Nile. It turns into Akagera River, which eventually flows into Lake Victoria and forms the Nile River. Photo: Sam Ngendahimana.
A view of Nyabarongo river that is the longest river in Rwanda, part of the upper headwaters of the Nile. It turns into Akagera River, which eventually flows into Lake Victoria and forms the Nile River. Photo: Sam Ngendahimana.
Michel Nkurunziza