Burundi:
Provinces of Muramvya, Mwaro, Karuzi, Gitega et Kirundo.
Rwanda:
Districts of Nyagatare, Kayonza, Kirehe, Bugesera (Eastern Province), Kamonyi (Southern Province), Rulindo (Northern Province).
Tanzania:
Districts of Bukoba, Karagwe, Ngara, and Missenye (Kagera Region).
Uganda:
Districts of Kabale, Ntungamo, Isingiro and Rakai (and possibly parts of Mbarara and Kiruhura now outside the basin).