Bosnia and Herzegovina:
NA km; large sections of the Sava blocked by
downed bridges, silt, and debris
Botswana:
none
Bouvet Island:
none
Brazil:
50,000 km
British Indian Ocean Territory:
none
British Virgin Islands:
none
Brunei:
209 km; navigable by craft drawing less than 1.2 m
Bulgaria:
470 km (1987)
Burkina Faso:
none
Burma:
12,800 km